Mount system, pin support system and method of directed energy deposition for producing metal workpiece to mitigate distortion, and system for directed energy deposition

Abstract

To provide a system for manufacturing objects on a substrate, especially titanium and titanium alloy objects, by directed energy deposition.SOLUTION: The present application relates to a mount system 100 and systems and methods using the mount system 100 for manufacturing objects on a substrate 300, especially titanium and titanium alloy objects, by directed energy deposition. The method includes: thermally pre-bending the substrate 300 onto which the object is to be manufactured to form a pre-bent substrate 300; attaching the pre-bent substrate 300 to a jig using the mount system 100 as an underlying support; preheating the substrate 300; and forming the object on the pre-heated, pre-bent substrate 300 using a directed energy deposition technique.SELECTED DRAWING: Figure 2A

Description

Technical Field

[0001] The present invention relates to devices and methods for reducing distortion in metal objects, particularly titanium and titanium alloy objects, manufactured using a directed energy deposition additive manufacturing process also known as solid freeform fabrication.

Background Art

[0002] Structural metal parts, such as those made of titanium or titanium alloy, are made by conventional manufacturing methods such as casting, forging, or machining from solid billets. These techniques often have the drawbacks of a large amount of material waste of expensive titanium metal being machined away, and long lead times associated with the manufacture of metal parts.

[0003] Overall high-density physical objects can be made by manufacturing techniques known as directed energy deposition (DED), rapid prototyping, rapid manufacturing, layered manufacturing, additive layer manufacturing, shaped metal deposition, or additive manufacturing. Metal DED is an additive manufacturing process that uses focused thermal energy to fuse materials by melting and deposit them. The additive manufacturing method stacks near-net shape products in layers, so it has a higher degree of manufacturing freedom and the potential to reduce costs. Also, while using the same established metal alloys, it is desirable to match the material properties of conventional bulk forming processes such as forging. DED is used for repair, rapid prototyping, and small / large quantity part manufacturing.

[0004] DED systems include multiple categories of machines that use one or a combination of energy sources based on arcs, such as laser beam (LB), electron beam (EB), or plasma arc (PA), gas tungsten arc (GTA), gas metal arc (GMA), etc. The metal raw materials used in DED systems usually include metals in the form of powder and / or wire. DED is typically carried out under an inert gas (e.g., DED using an arc-based or LB system) or in a vacuum (EB system) atmosphere. These are the main methods actually adopted, but other energy sources, raw materials, and atmospheres can also be used in any arbitrary combination.

[0005] Residual stress can be defined as self-equilibrating stress existing in an elastic body even in the absence of external loads such as thermal and / or mechanical ones. A large amount of welding-induced residual stress may be generated and accumulated during DED of a metal preform due to local heating and cooling cycles in which a heat source melts a metal material, deposits each new metal layer, and remelts the previously solidified metal layer. The incompatible elastic and / or plastic strain fields generated during DED of metals caused by non-uniform thermal loads in the vicinity of the processing area lead to an inevitable accumulation of complex thermally induced residual stress and strain during layer-by-layer manufacturing. Thermal expansion and contraction can occur as a result of transient thermal expansion and steep thermal gradients that may exist during DED. The formation and relaxation of residual stress in DED of metals can cause undesirable plastic deformation in regions adjacent to the processing zone, and this deformation may be carried over to the as-deposited preform. Residual stress retained within the as-deposited DED preform can lead to a permanent loss of workpiece tolerance. This is because when released from a clamped fixture platform or jig, the workpiece self-equilibrates the residual stress field still present within the structure. Deformation induced by residual stress is of more concern for larger components. This is because larger temperature differences coexist along the DED build-up process. An inappropriate distribution of residual stress in a designed component can also lead to unexpected or early failure, i.e., in regions of high tensile stress that are prone to fracture and fatigue. Stress-relieving heat treatment is generally used to relieve the stress retained within the as-deposited preform by a DED manufacturing sequence. However, tolerance loss remains one of the major concerns in most DED processes.

[0006] Residual stresses in DED of metals generally result from the fact that different regions of the manufactured part experience different cycles of thermal expansion and contraction. The resulting thermal stresses can cause a non-uniform distribution of irreversible material deformation, and some of this deformation may remain after the material has cooled, resulting in an internal, fully self-equilibrated stress field within the workpiece. This self-equilibration can result in a metallic structure that is geometrically out of tolerance due to distortion or warping. All forms of DED processing involve a large amount of local heat supply to the top of the new deposition layer (exposed to the heat source), the interface between the newly deposited layer and the previous layer, and / or the substrate in order to achieve a properly fused interface.

[0007] Generally, in a DED manufacturing process, a heat source with a high heat concentration is used to generate rapid heating. The heat generated can cause thermal expansion of the material accompanied by a gradual decrease in yield strength. The heat generated by the heat source is utilized to melt the powder and / or wire feedstock and form a weld pool in a portion of the workpiece. Due to this locally applied energy, the weld area is rapidly heated relative to the surrounding area, which remains relatively cool throughout, and locally fused. Since the melted material cannot support a load, the stress under the heat source is close to zero. Slightly away from the energy application area, i.e., in the material near the melt pool and the build layer beneath it, the material expands as a result of heating but is restricted by the adjacent material and the lower temperature material beneath it, resulting in elastic compressive strain. As a result, the stress in the area adjacent to the heat source is compressed. Since the temperature in the area adjacent to the heat source is high and the yield strength of the material is low, the stress in these areas can be as high as the yield strength of the material at the corresponding temperature. As the heat energy source moves away from the energy application area, the heated and melted material cools and contracts as a solid, but the contracting metal is mechanically restrained by the adjacent underlying material. As cooling continues, the residual stresses within the object are distributed, and generally, the top layer where the material's contraction is prevented shows large tensile stresses, while the lower layers show balancing compressive stresses. Depending on the application, the tensile stresses generated in the top layer can approach the yield strength of the material. Regarding the balancing compressive forces, if the strain and compressive load they contain exceed the critical buckling load, buckling of the metal structural member can occur.

[0008] Due to the layer-by-layer nature of the DED process, the difference in heating and cooling loads imposed by each successive layer causes a spatial competition between material expansion and contraction, ultimately resulting in the accumulation of residual stresses in the manufactured object. Since the high-temperature layer of molten metal is deposited on top of the cooler layer in front of the building object, large local thermal gradients and large contractions can occur as heat from the heat source traverses the workpiece, introducing residual stresses into the workpiece due to a non-conforming strain field. The vertical and lateral shrinkage that occurs during solidification of layer on layer can amplify the accumulation of residual stresses within the as-deposited preform. This stress is a function of the material's tensile modulus, coefficient of thermal expansion, and rate of shrinkage during cooling. If the stresses resulting from such non-conforming strains remain in the finished part and are not relieved, the residual stresses can combine and react to generate internal forces that can cause undesirable distortions of the object, such as bending, buckling, rotation, etc. of the object. Residual stresses that can form during conventional additive manufacturing processes are sometimes large enough to cause significant distortion, misalignment, cracking, or the formation of stress-induced cracks in the additive manufactured object (see FIGS. 1A-1H).

[0009] Methods for measuring or predicting stress induction in a formed article, or for modeling it, are known in the art (see, for example, (Patent Document 1) (Sidhu et al. (2017)); (Patent Document 2) (Nguyen et al. (2018))). The prior art developed to address these drawbacks has achieved only limited success. For example, post-weld high-pressure mechanical rolling has been used to plastically deform the integrated material before the formation of subsequent layers (see, for example, Colegrove et al., UK Patent Application (Patent Document 3) (2012)). Peening processes such as those taught in (Patent Document 4) (Sidhu et al. (2015)) are taught to be useful for relieving the strain of each metal layer deposited during the construction of parts manufactured in an additive layer. In these processes, one or more impact treatment devices are used to peen or strike a common point on the workpiece in order to plastically deform at least a portion of the deposited layer after cooling. Each impact treatment device can strike the workpiece one or more times and can strike at a frequency of up to 20 Hz. Laser peening has also been used to impart residual compressive stress to the workpiece (see (Patent Document 5) Kramer et al. (2014)). These methods are not suitable for relieving residual stress in areas where peening or rolling tools are inaccessible for parts of complex shapes. Also, these methods can increase the time and complexity of manufacturing the workpiece, and thus may be overly costly or impractical to use.

[0010] These methods can also increase the waiting time between layers, adversely affect productivity, and limit the freedom of manufacturing. Excessive cooling between layer depositions can also increase the temperature difference between layers and further exacerbate the generation of residual stress. In the case of methods for physically processing the deposited layers, contaminants from the tools are also a concern because contaminants can enter between the layers of the final product in the lamination process.

[0011] Accordingly, there is a need in this technical field for an economical way to perform direct metal deposition at a certain metal deposition rate in a additive manufacturing system that results in metal products having reduced or minimized residual stress, or strain, or both, compared to what can be achieved with conventional additive manufacturing processes. It would be desirable to provide a DED process that reduces the incidence of residual stress or cracking in objects manufactured by DED. It would also be desirable to provide a DED process that reduces the incidence of local strain in the object being formed as additional metal layers are deposited.

Prior Art Documents

Patent Documents

[0012]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Means for Solving the Problems

[0013] Accordingly, the embodiments provided herein are directed to the manufacture of workpieces having reduced or minimized residual stress, or strain, or both, using an additive manufacturing process that substantially avoids one or more of the problems resulting from the limitations and drawbacks of the related art. Apparatus, systems, and methods are provided for reducing or minimizing residual stress or strain, or both, during metal additive manufacturing to achieve products having improved material quality, as embodied and broadly described herein. Such DED manufactured products having reduced such residual stress or strain exhibit improved strength, fatigue resistance, and durability. In an example, the apparatus, systems, and methods provided can improve the throughput and yield of DED formed products, resulting in workpieces within specified tolerances.

[0014] In an example, provided herein are methods and systems that can reduce unwanted heat transfer without imparting substantial defects or any defects to a workpiece. In an example, methods and systems as described can be configured to control a substrate contact interface of a structure lying beneath a substrate during DED manufacturing to reduce heat transfer from the substrate to a welding fixture or other underlying structure. In an example, the reduction in heat transfer can be achieved by providing a reduction in the surface area through which thermal energy can be transferred, an increase in the solid / gas / solid thermal insulation boundary between the substrate and the underlying structure, or a combination of both. In an example, methods and systems as described can avoid or minimize unwanted defects on the workpiece.

[0015] In an example, the methods and systems provided herein can also improve DED manufacturing by promoting an atmosphere with reduced contents of oxidizing agent and contaminating particles. In an example, the methods and systems provided herein can reduce or eliminate the need for a ceramic sheet, plate, or pylon as part of a support. In an example, the thermal insulation provided by a ceramic sheet, plate, or pylon can be achieved by increasing the presence of solid / gas / solid interfaces that can cleverly utilize the low thermal conductivity of the inert atmosphere used during DED manufacturing. In an example, by not using a ceramic sheet, plate, or pylon as a support, it may be possible to reduce the amount of moisture in the DED manufacturing atmosphere. In an example, by eliminating the use of a ceramic sheet, plate, or pylon, it may be possible to avoid introducing unwanted ceramic microparticles into the DED manufacturing atmosphere.

[0016] In an example, the methods and systems provided herein can also provide an elastic and durable system that can provide repeatable and predictable manufacturing uniformity.

[0017] In an example, the method provided herein can be used to manufacture medium to large (e.g., up to 3 m) DED forming components that cannot be easily manufactured using conventional additive manufacturing processes. Additionally, since typical large amounts of residual stress, strain, or combinations thereof in conventional DED metal structures are reduced or removed, it is possible to manufacture metal structures that are geometrically within the tolerances and specifications.

[0018] Residual stresses and strains are often regarded as significant barriers to the widespread acceptance of DED technology for metals, especially in safety-critical applications. Thus, the apparatuses, systems, and methods provided herein that can minimize residual stress or strain can open up new markets for DED-manufactured components or encourage broader acceptance. Further, the apparatuses, systems, and methods provided herein can effectively control residual stress and strain in DED metal structures, thus improving the material utilization efficiency of both the substrate and the DED material. Such improvements in material utilization, in conjunction with the manufacture of DED-manufactured products within tolerances, can result in reduced waste and rework and can significantly reduce DED manufacturing costs.

[0019] In an example, a DED manufacturing method is provided that includes pre-bending a metal substrate to form a plastically pre-bent substrate prior to DED of a single-sided metal structure. Also provided is a DED manufacturing method that includes pre-bending a metal substrate to form a plastically pre-bent substrate and pre-heating the pre-bent substrate prior to DED of the metal structure. Also provided is an apparatus for manufacturing components with reduced residual stress and strain by DED. This apparatus can be used in conjunction with a conventional DED energy source used to melt metal powder and / or wire feedstock. The apparatus can include a mounting system as a support structure lying beneath the plastically pre-bent substrate. Also provided is a system that uses a modified conventional DED energy source using CAD-CAM program instructions that, when executed, cause the DED process to follow the shape of the underlying mounting system.

[0020] A DED manufacturing method is provided that minimizes or prevents distortion of DED manufactured products. This can increase the efficiency of the manufacturing process, such as by minimizing waste of the substrate and the amount of deposition material that must be used. In particular, since the highest thermal induction stress field can be introduced into the first deposition layer and the distortion effect can be particularly seen in the substrate, the method provided herein can save substrate material that is sacrificed or lost in conventional additive manufacturing processes. The method can result in an improvement in the material utilization efficiency of both the substrate and the DED material compared to conventional methods. The method provided herein can effectively control the residual stress and distortion in the DED structure. Thereby, material waste can be reduced and the build-to-fly ratio or BTF ratio can be brought closer to unity. By reducing material waste and reducing or eliminating rework time, the manufacturing cost can be significantly reduced.

[0021] A mounting system is provided that can include a first side configured to interface with a welding fixture. The mounting system can include a second side that defines a curved profile and is configured to interface with a substrate. The second side can include a substrate interface area sized to correspond to the surface of the substrate with which the second side interfaces. The second side can also include a substrate contact area configured such that the mounting system physically contacts the substrate when the second side interfaces with the substrate. The mounting system can have a substrate contact interface defined as the ratio of the substrate contact area to the substrate interface area. The substrate contact interface may be defined as the percentage of the substrate interface area occupied or constituted by the substrate contact area. In an example, the substrate contact area may constitute or be equal to 0.1 to 20 percent of the substrate interface area.

[0022] In an example, the percentage of the substrate interface area constituted by the substrate contact area is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 or more, and can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or less. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.2 to 20, 0.2 to 15, 0.2 to 10, 0.2 to 5, or 0.2 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.3 to 20, 0.3 to 15, 0.3 to 10, 0.3 to 5, or 0.3 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.4 to 20, 0.4 to 15, 0.4 to 10, 0.4 to 5, or 0.4 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.5 to 20, 0.5 to 15, 0.5 to 10, 0.5 to 5, or 0.5 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.6 to 20, 0.6 to 15, 0.6 to 10, 0.6 to 5, or 0.6 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.7 to 20, 0.7 to 15, 0.7 to 10, 0.7 to 5, or 0.7 to 1. In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area can be in the range of 0.8 to 20, 0.8 to 15, 0.8 to 10, 0.8 to 5, or 0.8 to 1.In an example, the second side is configured such that the percentage of the substrate interface area constituted by the substrate contact area is in the range of 0.9 to 20, 0.9 to 15, 0.9 to 10, 0.9 to 5, or 0.9 to 1.

[0023] The mount system can include or be made of a non-magnetic metal. The mount system can include or be made of a metal having a melting point of 1350 °C or higher. The mount system can be or include or be made of a metal including austenitic stainless steel. Austenitic stainless steel can include carbon, chromium, copper, manganese, molybdenum, nickel, nitrogen, phosphorus, silicon, or any combination of two or more thereof. Austenitic stainless steel can include at least 18% chromium. Austenitic stainless steel can be 300 series stainless steel. Austenitic stainless steel can include 304 series stainless steel, 309 series stainless steel, 310 series stainless steel, 316 series stainless steel, 318 series stainless steel, 321 series stainless steel, or 330 series stainless steel, or a combination thereof.

[0024] The ceramic coating of the mount system can be applied to any one or more surfaces. The ceramic coating can include zirconium dioxide, zirconium dioxide stabilized by addition of yttrium oxide, yttrium aluminum oxide, alkaline earth metal silicate, ZrV2O7, Mg3(VO4)2, or a combination thereof. The mount system can include a nominal bending profile deflection of about 3 mm to about 35 mm. The mount system can include a bond coat to which the ceramic coating is applied.

[0025] In an example, the mount system can be reconfigurable. In an example, the curvature profile can be defined by one or more pins. In an example, the mount system can include at least a first pin among one or more pins arranged to have a first substrate support height and at least a second pin among one or more pins arranged to have a second substrate support height, where the first substrate support height is different from the second substrate support height.

[0026] In an example, the curvature profile can be defined by a grid support structure. In an example, the curvature profile can be defined by a curved clamp mold. Also provided is a pin support system having one or more pins in a reconfigurable arrangement on a welding jig, where the one or more pins have a variable substrate support height and are arranged to define a curvature profile.

[0027] In an example, at least one of the one or more pins includes a pin head portion including a substrate contact area, a collar portion, and a base portion configured to engage with a welding jig. In an example, the pin head portion can include a flat portion in at least a part of the lateral profile. In an example, the pin head portion can include a welding jig interface area. In an example, the one or more pins include austenitic stainless steel.

[0028] Also provided is a directed energy deposition method for manufacturing a metallic workpiece. This method includes forming a plurality of molten tracks on a first surface of a substrate of a metallic material using a first melting tool to preliminarily bend the substrate of the metallic material with thermal energy to produce a preliminarily bent substrate; using, when fixing the preliminarily bent substrate to a jig, the mount system or the pin support system described herein as a support structure lying beneath for supporting the preliminarily bent substrate; and using a plurality of clamps to fix the preliminarily bent substrate and the mount system or the pin support system supporting the preliminarily bent substrate to the jig. After the preliminarily bent substrate and the mount system or the pin support system are fixed to the jig, the method can include forming a metallic workpiece on a second surface of the substrate by a) depositing a layer of molten metal on the second surface of the substrate to form a base material and depositing subsequent layers of molten metal on the base material to form a metallic workpiece, or b) depositing a layer of metallic powder, melting the metallic powder on the second surface of the substrate to form a base material, depositing subsequent layers of the powder, and melting the powder on the base material to form a workpiece, by an additive manufacturing process, wherein the second surface of the substrate is on the opposite side of the first surface of the substrate. The method can include preheating the preliminarily bent substrate to a temperature of about 400 °C to about 900 °C while fixed to the jig by applying thermal energy to the second side of the substrate. Preliminarily bending the substrate can include inducing a thermal gradient in the substrate. In this method, a melting tool including a heat source selected from a laser beam, an electron beam, a plasma arc, a gas tungsten arc, a gas metal arc, and any combination thereof can be used. During preliminarily bending the first surface of the substrate, the application area of the thermal energy can reach a temperature that is the melting point of the metallic material, or a temperature that is about 5 °C to about 50 °C lower or higher than the melting point of the metallic material.While preliminarily bending the first surface of the substrate, the formation of the molten tracks can result in the formation of tensile stress at the respective centerlines of the molten tracks and the formation of compressive stress in areas away from the respective centerlines of the molten tracks when the substrate cools. The tensile stress at the centerline of the molten track can be within about 10% of the yield strength of the substrate. The tensile stress at the centerline of the molten track may exceed the magnitude of the yield strength of the substrate.

[0029] The preliminary bending step can include directing a cooling gas onto the molten tracks using a gas jet device to facilitate cooling of the molten tracks. By directing the cooling gas onto the molten tracks, a thermal gradient can be formed in the substrate, and residual stress can be imparted to the substrate during cooling. The gas jet device can direct the cooling gas onto the molten tracks at a rate of about 50 L / min to about 500 L / min. The cooling gas can be applied in a continuous stream, intermittently, or in a pulsed flow. The cooling gas can include an inert gas selected from among argon, helium, neon, xenon, krypton, and combinations thereof. The cooling gas can be applied at a temperature of 100 °C or less. The cooling gas can be applied at a temperature of 25 °C or less. The gas jet device can generate a turbulent flow of the cooling gas, a laminar flow of the cooling gas, or a combination of a turbulent flow and a laminar flow of the cooling gas. The gas jet device can include a plurality of nozzles, and the nozzles can direct the cooling gas in a direction away from the heat source of the melting tool, and at least one nozzle can direct the cooling gas onto the solidified metal of the molten track.

[0030] In the method provided herein, the melt tracks can be manufactured equidistant from each other. The distance between the melt tracks can be from about 10 mm to about 60 mm. The method can include determining the centerlines of each wall of the preform formed on the second surface of the substrate, and positioning the melt tracks on the first surface of the substrate about 10 mm to about 20 mm away from the centerlines of the walls of the majority of the preform or workpiece formed on the second surface of the substrate. Most of the melt lines can be formed on the first surface at one or more positions other than the positions corresponding to one or more areas occupied by one or more walls of the workpiece formed on the second side of the substrate.

[0031] In this method, the pre-bending can form a preliminarily bent substrate having uniform elastoplastic bending. The pre-bending of the substrate can be performed while the substrate is clamped to the jig and thermally isolated from the jig. The substrate can be clamped to the jig using a plurality of clamps, and one or more of the clamps can include an insulating coating on each surface in contact with the preliminarily bent substrate. The insulating coating can include a ceramic material, silicon carbide, silicon nitride, boron carbide, or a combination thereof. The ceramic material can include alumina, zirconia, titanium oxide, alkaline earth metal silicate, aluminum titanate, zirconium dioxide, zirconium dioxide stabilized by addition of yttrium oxide, yttrium aluminum oxide, ZrV2O7, Mg3(VO4)2, or a combination thereof. The thickness of the insulating coating can be from 0.1 mm to 5 mm. The clamp can include a knurling pattern or a corrugation on the surface in contact with the preliminarily bent substrate. The clamp can be tightened to conform the preliminarily bent substrate to a curved profile defined by a mounting system or a pin support system. Each of the clamps can be tightened to a torque of from about 10 N·m to about 100 N·m. The clamp can be positioned such that the clamps intersect at the start or end of the wall of the workpiece being manufactured.

[0032] In the method provided herein, the preheating of the pre-bent substrate can be carried out using one or more melting tools including a DED heat source under the conditions of a) forming a melting track without melting the surface of the pre-bent substrate, or b) forming a melting track and melting the surface of the pre-bent substrate with the melting track. The positioning of the melting tool can be carried out at a stand-off position farther from the stand-off position used for the formation of the workpiece.

[0033] The method can include preheating a pre-bent substrate including a first short side and an opposing second short side, and a first long side and an opposing second long side, by: a) positioning a melting tool including a DED heat source on the first short side and within a range of about 10 mm to about 60 mm from the first long side of the pre-bent substrate fixed to the jig; b) applying thermal energy from the DED heat source of the melting tool across the surface of the pre-bent substrate starting from the first short side to the opposing second short side across the surface of the substrate to form a first energy application line on the surface; c) displacing and repositioning the DED heat source of the melting tool by a distance of about 10 mm to about 60 mm with respect to the first short side and from the first energy application line towards the second long side; and d) repeating steps b) and c) until the energy application line is applied across the surface of the pre-bent substrate to a position about 10 mm to about 60 mm from the second opposing long side. The preheating can raise the temperature of the pre-bent substrate to a temperature of about 350 °C to about 650 °C.

[0034] The formation of the metal workpiece can include providing a metal material in the form of a wire; using a single melting tool to heat and melt the metal material such that the melted metal material is deposited on an area of the substrate to form a base material; and moving the base material in a predetermined pattern with respect to the position of the melting tool such that the continuous deposition of the melted metal material on the base material solidifies to form a three-dimensional object.

[0035] The formation of a metallic workpiece can include: a) providing a metallic material in the form of a wire; b) using a first melting tool to heat at least a portion of the surface of a substrate to form a pre-heated area on the substrate; c) using a second melting tool to heat and melt the metallic material such that the melted metallic material is deposited on the pre-heated area to form a base material; d) relatively moving the base material in a predetermined pattern relative to the positions of the first melting tool and the second melting tool; e) using the first melting tool to heat at least a portion of the surface of the base material to form a pre-heated area on the base material and depositing the molten metallic material produced by the second melting tool that melts the metallic material on the pre-heated area on the base material; and f) repeating steps d) and e) such that the continuous deposition of the molten metallic material on the pre-heated area on the base material solidifies to form a three-dimensional object.

[0036] The method can include using a gas jet device to direct a cooling gas so as to impinge on the surface of the solidified material adjacent to the liquid-solid interface of a molten metal material, or any combination thereof; and moving a base material relative to the positions of a melting tool and the gas jet device in a predetermined pattern such that a continuous deposit of the molten metal material solidifies to form a three-dimensional object. The first melting tool can include a PTA torch, a laser device, a coaxial powder feeding nozzle laser system, an electron beam device, or any combination thereof, and the second melting tool can include a PTA torch, a laser device, a coaxial powder feeding nozzle laser system, an electron beam device, or any combination thereof. The first melting tool can include a first PTA torch, and the second melting tool can include a second PTA torch. The first melting tool can include a laser device, and the second melting tool can include a PTA torch. The first melting tool can include a PTA torch, and the second melting tool can include a laser device. The first melting tool can include a coaxial powder feeding nozzle laser system, and the second melting tool can include a laser device. The first melting tool can include a coaxial powder feeding nozzle laser system, and the second melting tool can include a PTA torch. The first melting tool can include a PTA torch, and the second melting tool can include an electron beam device. The first melting tool can include an electron beam device, and the second melting tool can include a PTA torch. The first melting tool can include an electron beam device, and the second melting tool can include a laser device. The first melting tool can include a laser device, and the second melting tool can include an electron beam device. When the second melting tool includes a PTA torch, the PTA torch can be electrically connected to a DC power source such that the electrode of the PTA torch serves as the cathode and the metal material serves as the consumable electrode that is the anode.

[0037] In the methods provided herein, each step of the method including pre-bending a substrate, pre-heating the pre-bent substrate, and forming a metal workpiece can be performed within a sealed chamber containing an inert atmosphere. The inert atmosphere can include argon, neon, xenon, krypton, helium, or combinations thereof.

[0038] Also provided is a system for directed energy deposition. The system can include a fixture for securing a pre-bent substrate; a mounting system or pin support system as described herein positioned between the fixtures and when the pre-bent substrate is secured to the fixture; an insulating clamp for securing the pre-bent substrate to the fixture; one or more melting tools comprising a DED heat source for melting a metal source into a molten metal that is deposited onto the surface of a base material; a gas jet device for directing a cooling gas to impinge on a solidified material adjacent to a liquid melt pool, or a liquid-solid interface of any combination thereof; a supply of the cooling gas; and an actuator for positioning and moving the base material relative to the melting tool and the gas jet device.

[0039] Additional features and advantages of the embodiments described herein will be described in the following description, will be apparent in part from the description, or can be learned by practice of the invention. The objectives and other advantages of the exemplary embodiments will be realized and achieved by the structure particularly pointed out in the written description and claims here, as well as the appended drawings.

[0040] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

[0041] The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0043] Detailed description of the illustrated embodiments Next, reference is made in detail to embodiments of the present invention, examples of which are shown in the accompanying drawings.

[0044] A. Definitions

[0045] All technical and scientific terms used herein shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains, unless otherwise defined. All patents, patent applications, published applications and publications, websites, and other published materials referenced throughout this specification are hereby incorporated by reference in their entirety, unless otherwise indicated. In the event of multiple definitions of a term in this specification, the definitions in this section shall prevail.

[0046] As used herein, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

[0047] As used herein, ranges and amounts can be expressed as "about" a particular value or range. "About" also includes the exact amount. Thus, "about 5%" means both "about 5%" and also "5%". "About" means within the range of typical experimental error for the intended use or purpose.

[0048] As used herein, "optional" or "optionally" means that the subsequent recited event or circumstance may or may not occur, and that the description includes both examples where the event or circumstance occurs and examples where it does not. For example, an optional component within a system means that the component may or may not be present within the system.

[0049] As used herein, "combination" refers to any association between two items or between more than two items. This association may be spatial or may refer to the use of two or more items for a common purpose.

[0050] As used herein, the terms "comprising", "including", and "containing" are synonymous and are inclusive or open-ended. Each term indicates that additional unrecited elements or method steps may optionally be included.

[0051] As used herein, "and / or" means "either or both" of the elements so combined, i.e., elements that in some cases coexist conjunctively and in other cases exist disjunctively. Multiple elements listed together with "and / or" should be construed in the same manner, i.e., construed as "one or more" of the elements so combined. Other elements may optionally exist, whether or not they are specifically related to those elements specifically identified by the "and / or" clause, other than the elements specifically identified by the "and / or" clause. Thus, by way of non-limiting example, reference to "A and / or B", when used in combination with open-ended language such as "comprising", in one embodiment, only A (optionally including elements other than B); in another embodiment, only B (optionally including elements other than A); in yet another embodiment, both A and B (optionally including other elements), etc. can be meant.

[0052] As used herein, "additive manufacturing" is also known as "additive layer manufacturing", "solid freeform fabrication", "directed energy deposition", "formable metal deposition", "layered manufacturing", and refers to an additive process of fabricating successive layers of an object. This process can employ 3D model data, a source of metallic material such as wire or powder, a heat source for melting the metallic source (such as a plasma arc, laser or electron beam), or a combination thereof.

[0053] As used herein, "additive manufacturing system" refers to a system used for additive manufacturing.

[0054] As used herein, "Directed Energy Deposition" or "DED" refers to an additive manufacturing process in which a heat source is used to fuse materials, particularly metals, by melting them as they are deposited.

[0055] As used interchangeably herein, the term "plasma transferred arc torch" or "PTA torch" refers to any device capable of heating a flow of inert gas by an electric arc discharge to excite it into a plasma, and then transferring the flow of plasma gas containing the electric arc through an orifice (such as a constriction nozzle) to the outside, emerging at high speed from the nozzle orifice, and forming a highly collimated arc column of ionized plasma gas that transfers the high heat of the arc to a target area such as a metal wire or substrate.

[0056] As used herein, the term "metallic material" refers to any known or conceivable metal or metal alloy that can be employed in a directed energy deposition process to form a three-dimensional object. Examples of suitable materials include, but are not limited to, titanium and titanium alloys, such as the Ti-6Al-4V alloy.

[0057] As used herein, "heat source" refers to a part of a device through which thermal energy can be transferred to a metallic material such as a metal wire or metal powder, or a substrate or base material, or any combination thereof. Exemplary heat sources include plasma arcs, laser beams, and electron beams.

[0058] As used herein, "melting tool" refers to a device that generates a heat source for preheating or melting part or both of the surface of a metallic material or workpiece in a DED additive manufacturing process. Examples include a PTA torch that generates an electric arc plasma as the heat source, a laser device that generates a laser beam as the heat source, and an electron beam device that generates an electron beam as the heat source.

[0059] As used herein, the term "base material" refers to the target material onto which molten metal is deposited to form a workpiece. This is the substrate when depositing the first layer of metallic material. When one or more layers of metallic material are deposited on the substrate, the base material is the topmost layer of the deposited metallic material onto which a new layer of metallic material is deposited.

[0060] As used herein, the term "workpiece" refers to a metallic body or object manufactured using directed energy deposition.

[0061] As used interchangeably herein, the terms "computer-aided design model" or "CAD model" refer to any known or conceivable virtual three-dimensional representation of an object to be formed that can be employed in a DED system that adjusts the position and movement of a substrate and operates a source of metallic material such as a DED heat source and a metallic powder supply or a metallic wire supply device, such that a physical object is constructed by fusing successive deposits of metallic material onto the substrate, and as a result, the physical object is constructed according to the virtual three-dimensional model of the object. This can be obtained, for example, by first dividing the virtual three-dimensional model into a set of virtual parallel layers and then dividing each of the parallel layers into a set of virtual quasi-one-dimensional pieces to form a virtual vectorized layered model of the three-dimensional model. Next, a controller can be engaged to deposit and fuse a series of quasi-one-dimensional pieces of metallic material feed onto the substrate in a pattern according to a first layer of the virtual vectorized layered model of the object to form a physical object.

[0062] The sequence is then repeated for a second layer of the object by depositing and fusing a series of quasi-one-dimensional pieces of weldable material onto the previously deposited layer in a pattern according to the second layer of the virtual vectorized layered model of the object. By this repetition, the deposition and fusion process is continued layer by layer for each successive layer of the virtual vectorized layered model of the object until the entire object is formed. However, the present invention is not bound to a particular CAD model and / or computer software for implementing a controller of the configuration according to the present invention, nor is the present invention bound to a particular type of controller. Any known or conceivable controller (CAD model, computer software, computer hardware, actuators, etc.) capable of constructing a metallic three-dimensional object by the directed energy deposition method can be used.

[0063] As used herein, "cooling gas" is a gas that is directed toward a surface that remains solidified, such as a melt track, to directly affect the cooling and solidification of the metal that remains solidified and to promote cooling and solidification. The temperature of the gas can be any temperature that cools the surface with which it interacts. The temperature can be less than 100 °C, or less than 50 °C, or less than 30 °C, or less than 25 °C, or less than 10 °C, or less than 5 °C, or less than 0 °C, or in the range of about -10 °C to about 100 °C, or about -5 °C to about 90 °C, or about 0 °C to about 80 °C. The temperature can be about 25 °C or less.

[0064] As used herein, "residual stress" is the stress that would exist in a structure even if all external loads were removed, due to the non-uniformity of residual strain. Residual stress usually self-equilibrates.

[0065] As used herein, "fixture" refers to a device used to hold or secure a workpiece, a mount system, and a clamp in a predetermined position during deposition. For example, a fixture can include a tray, pedestal, or platform that can hold the substrate or other part of the workpiece during the DED process.

[0066] As used herein, a "preform" is a workpiece manufactured by an additive manufacturing process. A preform may be an intermediate for a final finished part or a semi-finished part. A preform may have a near-net shape relative to the final finished part and, at a minimum, may require some further processing. For example, a preform may require final finishing for a high-tolerance configuration.

[0067] As used herein, the "billet-to-finished ratio" or "BTF ratio" refers to the weight ratio of the weight of the raw material used to manufacture a component to the weight of the finished product. This ratio may depend on how closely the shape of the as-deposited DED preform resembles the shape of the finished component. The greater the amount of material that needs to be removed from the DED preform to manufacture the final component, the higher the BTF ratio.

[0068] As used herein, the "length" or "length direction" with respect to a substrate refers to the direction along the largest of the three dimensions of the substrate.

[0069] As used herein, the "width" or "width direction" with respect to a substrate refers to the direction along the second largest of the three dimensions of the substrate, typically referring to the measurement from one short side to the other short side.

[0070] As used herein, the "thickness" or "thickness direction" with respect to a substrate refers to the direction along the smallest of the three dimensions of the substrate.

[0071] As used herein, "high-strength steel" refers to steel having a tensile strength of 300 MPa or more.

[0072] As used herein, "high-strength low-alloy steel" refers to steel having a tensile strength of 370 MPa or more.

[0073] As used herein, "ultra-high-strength steel" refers to steel having a tensile strength of 780 MPa or more.

[0074] As used herein, the "warm forming temperature" is a temperature below the recrystallization temperature of a material that maximizes the ductility of the material without allowing recrystallization, grain growth, and metallurgical failure. The warm forming temperature can range from about 200 °C to about 850 °C depending on the material.

[0075] As used herein, "hot forming temperature" is a temperature that exceeds the recrystallization temperature of the material. The hot forming temperature can range from about 600 °C to about 2000 °C depending on the material.

[0076] As used herein, "the back side of the substrate" refers to the side of the substrate that faces away from the deposition apparatus during DED manufacturing. For example, the back side of the substrate can face towards the jig during deposition. The back side of the substrate is the side opposite to the side where deposition is performed.

[0077] As used herein, "the front side of the substrate" refers to the side of the substrate that faces the deposition apparatus. For example, the front side of the substrate can be the side where the molten material is deposited during DED. The front side of the substrate can be the side where the workpiece is formed by DED. The front side of the substrate is the side opposite to the back side of the substrate.

[0078] As used herein, "cavity" refers to an unfilled space or void within a mass that does not cross the mass to form a hole. The cavity can be a drilled or cut-out space, or a space formed by adding additional material.

[0079] As used herein, the "nominal deflection" or "h (camber)" of a mount system is the difference between the maximum height of the arcuate surface measured at the center of the arcuate surface and the upper surface of the edge of the mount system.

[0080] Also, unless expressly indicated to the contrary, it should be understood that in a method that includes a plurality of steps or acts claimed herein, the order of the steps or acts of the method is not necessarily limited to the order in which the steps or acts of the method are recited.

[0081] B. Substrate Mounting System Conventional DED of metals for manufacturing preforms can introduce residual stresses into the preforms. Residual stresses in metal DED typically result from the fact that different areas of the manufactured component experience different cycles of thermal expansion and contraction. The resulting thermal stresses can cause a non-uniform distribution of irreversible material deformation, some of which remains after the material has cooled, potentially creating an internal, fully self-equilibrated stress field within the workpiece. If not relieved, this stress can promote a number of manufacturing defects. As shown in FIGS. 1A - 1H, workpieces (FIG. 1A) manufactured using conventional DED additive manufacturing without stress relief can exhibit misalignments (FIGS. 1B and 1C), cracks (FIGS. 1D, 1E, and 1F), and fractures (FIGS. 1G and 1H). A substrate mounting system 100 is provided as a support structure lying beneath a pre-bent substrate for manufacturing a single-sided metal component without residual stress or strain due to DED, or a metal component with reduced residual stress or reduced strain. The mounting system 100 can be used in conjunction with conventional DED heat sources used to melt metal powder or wire feedstock, or combinations thereof.

[0082] In an example, the mounting system 100 can be employed as an intervening structure between a pre-bent substrate and a jig. One or more clamps can be used to secure the pre-bent substrate to the jig. As a result, the pre-bent substrate is pressed towards the jig, such that the force required to secure the pre-bent substrate to the jig is applied between the clamp and the jig, and the mounting system 100 serves as a support between the substrate and the jig. In an embodiment, the pre-bent substrate is pressed axially downwards.

[0083] In an example, the mount system 100 provided herein can make the redesign of the fixture simpler, i.e., lighter, cheaper, and more versatile. Current fixtures may be overdesigned assuming the reaction forces and stresses encountered when clamping the substrate directly to the fixture or during DED. The mount system 100 can reduce these assumed forces and stresses. Also, the mount system 100 provided herein can allow for a change in the clamping arrangement compared to conventional clamping arrangements. In some applications, when the mount system 100 is used, the entire perimeter of the substrate can be clamped to the fixture.

[0084] In an example, the mount system 100 can allow for low or reduced heat energy transfer between the substrate and the welding fixture during DED manufacturing, reduce or eliminate the need for insulating ceramics, obtain a manufactured product that is defect-free or substantially defect-free, or achieve any combination thereof.

[0085] As described above, the ceramic sheets, plates, or pylons used as thermal insulators can absorb moisture released during DED manufacturing. The release of moisture in the environment can lead to oxidation of the deposited metal, increasing the presence of oxygen, which can be harmful to the process. In an example, the mount system 100 can eliminate the ceramic sheet, plate, or pylon. In an example, the mount system 100 can be used without ceramics. In an example, no ceramic coating is used on the mount system 100. In an example, the mount system 100 does not include any ceramic material. In an example, the mount system 100 does not include any ceramic sheet, plate, or pylon. In an example, the mount system 100 may include a ceramic material and / or a ceramic coating.

[0086] The mounting system 100 may be configured to include a predetermined "substrate contact interface". As used herein, the term "substrate contact interface" with respect to the mounting system 100 refers to the ratio of the substrate contact area of the mounting system 100 to the substrate interface area of the mounting system 100. The "substrate interface area" of the mounting system 100 refers to the area on one side of the mounting system 100 that is configured to be occupied by the surface of the substrate or the preliminarily bent substrate facing the mounting system 100 during use, and thus corresponds to the area of the surface of the substrate or the preliminarily bent substrate facing the mounting system 100 during use of the mounting system 100. An exemplary substrate interface area 106 (shown as a plane by a dashed line) of the mounting system 100 is shown in FIG. 2B (curvature is omitted for clarity). In the example, the substrate interface area of the mounting system 100 may be the same as or different from the surface area of the physical surface of the mounting system 100 configured to face the substrate or the preliminarily bent substrate when the mounting system 100 is in use. For example, in the example shown in FIG. 2B where the mounting system 100 may include a set of separate elements 101, the substrate interface area 106 may be larger than the collective surface area of the elements 101 configured to face the substrate or the preliminarily bent substrate when the mounting system 100 is in use. The term "substrate contact area" as used herein refers to the area where physical contact occurs between the mounting system 100 and the substrate or the preliminarily bent substrate when the mounting system 100 is in use. For the purposes of this description, referring to the "substrate contact area" of the mounting system 100 as a whole should be understood as the total surface area of the mounting system 100 configured to physically contact the surface of the substrate or the preliminarily bent substrate when the mounting system 100 is used as described herein. Physical contact in this definition also includes contact with an intervening ceramic coating, bond coat, or both. For ease of reference, the ratio representing the substrate contact interface can be expressed as a percentage of the portion of the substrate interface area of the mounting system 100 that is the substrate contact area of the mounting system 100.In other words, in this specification, the ratio can be expressed as a percentage or proportion of the area occupied by the area of the side of the mounting system 100 configured to be stacked by the substrate or the preliminarily bent substrate when the mounting system 100 is in use, out of the area of the side of the mounting system 100 that physically contacts the substrate or the preliminarily bent substrate when the mounting system 100 is in use. The substrate contact interface can be similarly understood as the ratio of the surface area of the side of the substrate or the preliminarily bent substrate that is configured to physically contact the mounting system 100 when supporting the substrate or the preliminarily bent substrate.

[0087] In an example, the mounting system 100 can be configured to include a substrate contact interface that is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 or more, and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or less. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.2 to 20, 0.2 to 15, 0.2 to 10, 0.2 to 5, or 0.2 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.3 to 20, 0.3 to 15, 0.3 to 10, 0.3 to 5, or 0.3 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.4 to 20, 0.4 to 15, 0.4 to 10, 0.4 to 5, or 0.4 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.5 to 20, 0.5 to 15, 0.5 to 10, 0.5 to 5, or 0.5 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.6 to 20, 0.6 to 15, 0.6 to 10, 0.6 to 5, or 0.6 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.7 to 20, 0.7 to 15, 0.7 to 10, 0.7 to 5, or 0.7 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.8 to 20, 0.8 to 15, 0.8 to 10, 0.8 to 5, or 0.8 to 1. In an example, the mounting system 100 can be configured to have a substrate contact interface in the range of 0.9 to 20, 0.9 to 15, 0.9 to 10, 0.9 to 5, or 0.9 to 1.

[0088] In an example, the mount system 100 can be configured to have a desired substrate contact interface for a substrate or a pre-bent substrate of a given size by controlling or adjusting a portion of the mount system 100 configured to physically contact the substrate or the pre-bent substrate. In an example, the substrate contact area of the mount system 100 can be controlled by making the surface ("substrate contact surface") of the mount system 100 that faces and is configured to physically contact the substrate or the pre-bent substrate during use uneven or discontinuous. In an example, as described herein, the substrate contact surface of the mount system 100 may be corrugated, knurled, or may include raised portions and valleys or similar uneven surface contours in another way. In an example, the substrate contact surface of the mount system 100 is designed to have steps, curves, convex surfaces, concave surfaces, hollows, irregularities, or any other uneven profile that can result in a substrate contact area that is only a portion of the total surface area of the substrate contact surface of the mount system 100. In an example, the mount system 100 may be configured to support the substrate or the pre-bent substrate only at spaced positions, such as by a set of pins or pin structures, or by a lattice structure.

[0089] In an example, reducing the substrate contact area can result in a reduction in conductive heat transfer from the substrate or the pre-bent substrate to the mount system 100, the welding fixture, or both. In an example, this can promote heat accumulation in the substrate during the DED process and thus potentially minimize the degree of spatter. In an example, the thermal gradient across the thickness of the substrate or the pre-bent substrate can be substantially smaller during the deposition of the first layer, so the welding-induced residual stress that occurs during the DED of the metal preform can be reduced. Also, titanium and titanium alloys, such as Ti-6Al-4V, have high yield stresses and relatively low elastic moduli, so these metals exhibit high spatter at room temperature.

[0090] In an example, due to the reduction of the substrate contact area, one or more gaps or spaces may be formed between the substrate or the pre-bent substrate and the mounting system 100, the welding jig, or both. In an example, it may be possible to fill these gaps or spaces with the atmosphere of the DED chamber or a noble gas such as argon that can act as a thermal insulator. Noble gases such as argon gas may be very effective thermal insulators. Also, since the solid / gas / solid interface has a rather low thermal conductivity, these specific interfaces between the pre-bent substrate / argon gas / mounting system and / or the welding jig may effectively function as a thermal barrier. Thus, in an example, one or more gaps or spaces may also help to minimize the average heat transfer rate between the substrate or the pre-bent substrate and the mounting system 100.

[0091] In an example, the mounting system 100 may include a single integral structure, an array of elements or structures, or a combination of both. Any structure that reflects the design characteristics of the mounting system 100 described herein may be used to practice the mounting system 100. In an example, the mounting system 100 may include a pin support system 110, one or more pins 112, a grid support system 150, a mold 170, any similar structure, or any combination thereof. These exemplary structures of the mounting system 100 are provided by way of example and should not be regarded as limiting. In an example where the mounting system 100 includes an array of elements or structures, and each element or structure has its own substrate contact surface and substrate contact area, the substrate contact interface as previously defined when referring to the mounting system 100 as a whole should be understood as a function of the total substrate contact area from all elements or structures within the array that are part of the mounting system 100.

[0092] In an example, the mount system 100 provided herein can be self - supporting. In an example, the mount system 100 can be separated from and detached from a jig. In an example, the mount system 100 can be integrated as part of a welding jig. In an exemplary embodiment, the mount system 100 can be configured to be installed on a welding jig.

[0093] In an example, the mount system 100 can be configured to define a curved profile 102 on at least one side. In an example, the curved profile 102 corresponds to the surface profile of the mount system 100. In an example, the curved profile 102 is the profile of the plane that defines the mount system 100. In an example, the curved profile 102 is the surface profile of the mount system 100. In an example, when the mount system 100 is an integral structure such as a mold or can be provided within a lattice as described herein, the curved profile 102 can be the surface profile of the mount system 100. In an example, when the mount system 100 includes a discontinuous surface such as can be provided within a lattice as described herein, or when the mount system 100 includes an array of elements or structures 101 such as a pin - support system as described, the curved profile 102 can be a profile defined as a plane that crosses the respective distal ends of the substrate contact areas on the discontinuous surface or on the elements or structures within the array, as shown in FIG. 2A.

[0094] In an example, the mount system 100 can be configured to define a curved profile 102 on at least the side facing away from the welding jig. In an example, the mount system 100 can be configured to define a planar profile on one side. In an example, the mount system 100 can be configured to define a planar profile on a first side and a curved profile on a second, opposite side. In an example, the mount system 100 can define a planar or flat profile on a first side that is intended to face or be oriented towards the welding jig during use. In an example, the mount system 100 can define a curved profile 102 on a second side opposite the first side. In an example, the mount system 100 can define a curved profile 102 on a side that, during use, faces away from the welding jig or is oriented away from the welding jig and towards or is intended to face the substrate or a pre-bent substrate. In an example, the curved profile 102 of the mount system 100 is configured to face the substrate or a pre-bent substrate during use of the mount system 100. In an example, the curved profile 102 is provided on the side of the mount system 100 that is configured to interface with the substrate or a pre-bent substrate during use of the mount system 100. In an example, the curved profile 102 of the mount system 100 is configured to interface with the substrate or a pre-bent substrate.

[0095] In an example, the curvature of the bending profile 102 of the mount system 100 can be determined empirically based on data collected in initial tests conducted using a ceramic plate. The ceramic plate was cut into different sizes and used to generate different current curvatures, and tested for its ability to minimize the distortion of the preform prepared on the bending support. Subsequently, modeling was used to confirm that the curvature used in the experiment would result in a final result close to the target, i.e., a preform without distortion. In a cross-section viewed from the side, the shape of the bending profile 102 of the mount system 100 may resemble the upper half of an ellipse where the minor axis is much smaller than the major axis. The ellipse can have an eccentricity close to 1 but less than 1 (an eccentricity of 1 results in a flat surface).

[0096] In an example, the mount system 100 may include a peripheral rim portion 104. This example is shown in FIG. 2A. In an example, the peripheral rim portion 104 may be present along at least the side edges, or along the periphery of an area defined by the first side, the second side, or both the first and second sides of the mount system 100. In an example, the peripheral rim portion 104 of the mount system 100 may be configured to support at least a portion of the substrate or the pre-bent substrate at the portion where the substrate or the pre-bent substrate is clamped to the welding jig when the mount system 100 is in use. In an example, at least a portion of the peripheral rim portion 104 of the mount system 100 may be configured to support the substrate or the pre-bent substrate at the position where the substrate or the pre-bent substrate is clamped to the welding jig when the mount system 100 is in use.

[0097] In an example, some compressive stress may be felt in the mount system 100 due to the contact between the mount system 100 and the substrate or the pre-bent substrate. In an example, the mount system 100 can be made of a rigid material resistant to torsion and deformation to help maintain its shape. Further, the mount system 100 can be made of a material resistant to thermal shock, corrosion, and / or non-magnetic.

[0098] In an example, the mount system 100 can function as a support structure for a pre-bent DED substrate positioned between the pre-bent DED substrate and a jig. An exemplary arrangement can include the jig as the bottom surface against which the mount system 100 is positioned.

[0099] In an example, the back side (first side) of the pre-bent substrate where a melt track can be present can be positioned to face the side of the mount system 100 that faces away from the jig. In this configuration, the back side of the pre-bent substrate faces downward toward the curvature profile 102 of the mount system 100 and the jig. In an example, one or more clamps can secure the pre-bent substrate to the jig with the mount system 100 sandwiched between the pre-bent substrate and the jig. In an example, the force exerted by the clamp on the pre-bent substrate can straighten the pre-bent substrate and conform it to the curvature of the curvature profile 102 of the mount system 100. One or more clamps around at least a portion of the periphery of the DED substrate can compress the pre-bent substrate uniformly downward toward the jig and secure the pre-bent substrate to the jig.

[0100] In an example, the mount system 100 can help reduce or eliminate deformations, such as welding-induced buckling distortion, caused by elastic instability due to compressive residual stress when the critical buckling stress of the substrate is exceeded. Due to the reduced contact interface that the mount system 100 is configured to have with respect to the substrate or a pre-bent substrate, a controlled substrate interface, or combinations thereof, in an example, the mount system 100 may be able to minimize the occurrence of large local stains and local temperature gradients that can induce resulting deformation patterns. In an example, the mount system 100 can maintain a consistent interface with the pre-bent substrate in order to optimize the thermal and mechanical homogeneity across the pre-bent substrate.

[0101] In an example, the dimensions of the substrate can be selected to receive one or more workpieces constructed thereon. Typically, the only limitation regarding the size of the curvature profile 102 defined by the mount system 100 with respect to the substrate is that the substrate or pre-bent substrate can be clamped to the fixture with the mount system 100 positioned between the substrate and the fixture. The mount system 100 can be designed to define a curvature profile 102 of the same size as the substrate or pre-bent substrate. In an example, the mount system 100 can be configured to define a curvature profile 102 that is 0.5% to 10% larger than the bonding surface of the substrate or pre-bent substrate as long as the substrate or pre-bent substrate can be clamped to the fixture.

[0102] As long as the substrate does not contact the fixture when clamped to the fixture with the mount system 100 between the substrate and the fixture, the mount system 100 can be designed to define a curvature profile 102 having a size that is 0.05% to 2.5% smaller than the substrate.

[0103] In the embodiments provided in this specification, when the mounting system 100 is placed on a welding jig, when measured from the surface of the welding jig facing the mounting system 100, the height of the curved profile 102 defined by the mounting system 100 at or near the center or apex of the curved profile 102 can be in the range of about 3 mm to about 60 mm, or about 12 mm to about 50 mm, or about 15 mm to about 45 mm. The height of the curved profile 102 measured at or near the outer edge or peripheral rim portion can be in the range of about 0.5 mm to about 55 mm, or about 3 mm to about 45 mm, or about 10 mm to about 40 mm. The thickness profile of the curved profile 102 when viewed from the side has a maximum height at the center or apex, and the height may gradually decrease toward the outer edges or peripheral rim portion to from a curved surface. The difference in height across the cross-section of the curved profile 102 defined by the mounting system 100 can result in a concave downward curve on the upper surface of the curved profile 102. In the cross-section viewed from the side, the shape of the curved profile 102 may resemble the upper half of an ellipse whose semi-minor axis is much smaller than its semi-major axis. The ellipse can have an eccentricity close to 1 but less than 1 (an eccentricity of 1 is a flat surface).

[0104] In an example, the mount system 100 can be composed of any metal having sufficient strength and temperature resistance to be used under typical conditions of DED processing. The mount system 100 can be made of a corrosion-resistant metal. The mount system 100 can be made of a heat-resistant metal. The mount system 100 can be made of a non-magnetic metal. The mount system 100 can be made of a metal having a melting point of 1350 °C or higher. In some configurations, the mount system 100 can include austenitic stainless steel. Austenitic stainless steel can include carbon, chromium, copper, manganese, molybdenum, nickel, nitrogen, phosphorus, silicon, or combinations thereof. Austenitic stainless steel can include at least 18% chromium. The mount system 100 can be made of 300 series stainless steel. The mount system 100 can be made of stainless steel of the 304, 309, 310, 316, 318, 321, or 330 series. The mount system 100 can be made of grade AISI 330 stainless steel. The mount system 100 can be made of non-magnetic metal to avoid an unbalanced magnetic field condition surrounding the welding arc in an arc-based DED system, which can cause numerous processing problems such as magnetic arc blow.

[0105] In an example, the mount system 100 can be employed without using a ceramic sheet, plate, or pylon, i.e., they can be excluded. As described above, excluding ceramic elements such as ceramic sheets, plates, or pylons can be advantageous in maintaining a low-level oxygen or oxygen-free atmosphere. In an example, replacing the conventional ceramic insulation sheet with the mount system 100 can significantly stabilize the processing chamber atmosphere because the amount of water vapor released into the chamber from the ceramic coating of the mount system 100 during DED processing is less or non-existent compared to the amount of water vapor released from a conventional alumina ceramic plate.

[0106] In an example, the use of the ceramic coating can be carried out in the mounting system 100 if desired. In an example, the ceramic coating as described herein may not present the same problems as those considered with respect to a ceramic sheet, plate, or pylon. The advantage of the ceramic coating is to further minimize or better prevent the heat energy transfer from the substrate or pre-bent substrate to the mounting system 100, from the mounting system 100 to the welding jig, or both during the DED process. The further reduction of heat energy transfer may lead to the reduction of heat loss from the substrate or pre-bent substrate during DED.

[0107] In an example, the ceramic coating can be applied to a portion or area of the mounting system 101 configured to be the contact interface between the mounting system 101 and the substrate or pre-bent substrate. In an example, the ceramic coating can be applied to a portion or area of the mounting system 101 configured to be the contact interface between the mounting system 101 and the welding jig. Any of the above combinations can also be adopted. Also, in an example, additional ceramic coatings or elements can be adopted. In an example, the mounting system 100 may be contoured by a metal material and may not be coated with a ceramic coating or bond coat at the periphery or peripheral rim of the curved profile 102 defined by the mounting system 100.

[0108] In an example, the ceramic coating 108 can be applied directly to the surface of the mounting system 100, or the ceramic coating can be applied to a bond coat 107 that is directly applied to the surface of the mounting system 100.

[0109] The ceramic coating can be applied using any process including chemical vapor deposition or electrochemical deposition such as atmospheric plasma spraying, magnetron sputtering, electrophoretic deposition, or physical vapor deposition such as electron beam physical vapor deposition. Any high-temperature ceramic coating known in the art can be used (see, for example, U.S. Patent Nos. 4,321,310 (Ulion et al., 1982), 5,789,330 (Kondo et al., 1998), 5,304,519 (Jackson et al., 1994), 6,387,539 (Subramanian, 2002), and 6,998,064 (Gadow et al., 2006)). Exemplary types of ceramic coatings include zirconium dioxide, zirconium dioxide stabilized by the addition of yttrium oxide, yttrium aluminum oxide, alkaline earth metal silicates, ZrV2O7, Mg3(VO4)2, and combinations thereof. The mount system 100 can be coated with plasma-sprayed ZrO28Y2O3, such as Metco (trademark) 22xx and 23xx powders including zirconium dioxide stabilized by the addition of yttrium oxide, e.g., Metco 222A, 231A, 233A, 233B, 233C, and 234A (available from Oerlikon Metco (Frankfurt, Germany)). The coating can comprise multiple layers of different types of ceramics, or multiple layers of one type of ceramic.

[0110] The ceramic coating used for the mount system 100 can be selected to be less hygroscopic than conventional alumina insulation. The ceramic coating used for the mount system 100 can be selected to be non-hygroscopic compared to conventional alumina insulation.

[0111] In an example, the mount system 100 can include a bond coat 107. The bond coat is a coating of a material that can enhance the adhesion between the substrate and the ceramic coating. The bond coat can impart corrosion resistance to the substrate to which it is applied. The bond coat can be used alone or in combination with the ceramic coating. The bond coat can include chromium and aluminum. The bond coat can include MCrAlY, where M is a metal selected from the group consisting of Co, Ni, Fe, Cr, Co, and combinations of Ni / Co. In some applications, the bond coat includes MCrAlY, where M is Ni, Co, or a combination thereof. Exemplary bond coat materials include Amdry™ powder products such as Amdry™ 962, 9621, 9624, 9625, 963, and 964 (available from Oerlikon Metco (Frankfurt, Germany)). The bond coat can be present with a thickness of about 1 to 250 μm.

[0112] The thickness of the ceramic coating applied to the mounting system 100 can vary depending on the type of ceramic used and its ability to support both mechanical and thermal loads. In some configurations, the total thickness of the ceramic coating can be from about 0.1 mm to about 5 mm, or from about 0.25 to about 4 mm, or from about 0.3 to about 3 mm. Each deposited layer can be thinner than the total amount of ceramic coating applied, but when all of the applied layers of ceramic are combined, they can form a ceramic coating that is at least 0.1 mm, or at least 0.25 mm, or at least 0.5 mm, or at least 0.75 mm, or at least 1 mm, or at least 1.25 mm, or at least 1.5 mm, or at least 2.0 mm, or at least 2.5 mm, or at least 3.0 mm, or at least 3.5 mm, or at least 4.0 mm, or at least 4.5 mm. The ceramic coating can have a thickness of 0.1 mm, or 0.25 mm, or 0.5 mm, or 0.75 mm, or 1 mm, or 1.25 mm, or 1.5 mm, or 2.0 mm, or 2.5 mm, or 3.0 mm, or 3.5 mm, or 4.0 mm, or 4.5 mm, or 5 mm.

[0113] In an example, the mounting system 100 may include knurling on at least a portion of the surface area configured to contact the substrate or the pre-bent substrate directly or with a ceramic coating interposed therebetween when the mounting system 100 is in use. The knurled surface can form a linear pattern, a slanted line pattern, a diamond pattern, or a combination thereof on the substrate contact surface. The diamond-shaped knurling can be performed to result in a male or female knurling pattern. In the male diamond pattern, raised points are formed. In the female diamond pattern, diamond indentations are formed. The knurling can result in pillars each having a linear side substantially perpendicular to the arc of the curvature profile 102 defined by the mounting system 100. The pillars can have a planar upper surface. The pillars can have a curved upper surface. The pillars can have a cross-section that is square, rectangular, circular, elliptical, rhomboidal, trapezoidal, triangular, pentagonal, hexagonal, heptagonal, nonagonal, decagonal, frustum-shaped, frustum pyramid-shaped, or any combination thereof. The pillars can be separated from each other by a space. The spacing between the pillars can be substantially constant.

[0114] In an example, the mounting system 100 can include a waveform or a wavy surface on at least a portion of the surface area configured to contact a substrate or a preliminarily bent substrate directly or with a ceramic coating 108 interposed therebetween when the mounting system 100 is in use. In an example, the surface of the mounting system 100 can be made wavy to include alternating ridges and grooves. In an example, the waveform can extend across the substrate contact surface of the mounting system 100. In an example, the waveform can extend from one long side of the mounting system 100 to the other long side. In an example, the waveform can extend from a first edge of the mounting system 100 to a second edge. In an example, the waveform can result in a plurality of pillars perpendicular to the arc of the curved profile 102. In an example, the waveform can extend along at least one edge of one or more elements or structures from an array of elements or structures that make up the mounting system 100.

[0115] In an example, the knurling 103 can be a pillar having a planar upper surface, as illustrated in FIG. 2C. In an example, the ridge can be a pillar having a curved upper surface. Also as shown, the knurling spacing 105 can have a planar bottom surface. In an example, the groove can have a curved or U-shaped bottom surface. The groove can include rounded corners to protect against stress concentration and crack propagation. Each ridge can have a taper with an increasing cross-section along its longitudinal axis. In cross-section, the ridge can have a trapezoidal shape. In cross-section, the ridge can have the shape of an isosceles trapezoid, where the long base of the trapezoid forms the bottom of the ridge and the short base of the trapezoid forms the top of the ridge. In cross-section, the ridge can have the shape of a convex isosceles trapezoid. In cross-section, the ridge can have the shape of a pyramid of a regular square pyramid.

[0116] A raised portion having a frustum shape, particularly a square pyramid shape, in cross-section can transmit stress from the top to the base of the raised portion while avoiding stress deformation of the raised portion due to applying pressure to the pre-bent substrate against the jig when the curved profile 102 of the mounting system 100 supports the pre-bent substrate. A raised portion having a frustum shape in cross-section can withstand the loads, forces, and moments that can be applied during the DED process. The forces and moments acting on the plateau (upper flat surface) of the raised portion can be transmitted to the base of the raised portion and ultimately to the back side of the mounting system 100. When the cross-section of the raised portion is in the shape of a frustum, the applied load can be transmitted to a larger surface area at the base of the raised portion. In an example, the knurled surface or valley between the raised portions can form an additional gap between the mounting system 100 and the substrate or the pre-bent substrate when the mounting system 100 is brought into contact with the pre-bent substrate. As described above, the gap can be filled with the atmosphere of the DED chamber or a noble gas such as argon that can act as a thermal insulator. Argon gas is a very effective thermal insulator. The solid / gas / solid interface may function effectively as a thermal barrier because its conductivity is quite low.

[0117] In an example, the knurling pattern or waveform of the mount system 100 can be covered by the ceramic coating layer 108 and optionally the bond coat 107, as described above and as shown, for example, in FIG. 2C. In an example, the ceramic coating can also be present in the valleys of the knurling pattern or the valleys of the waveform. The thickness of the ceramic coating alone is limited by the limits of application to the mount system 100 and the ability of the ceramic to support a substrate that has been pre-bent without damaging the ceramic coating when the substrate is clamped to the fixture and an axially downward clamping force. Because there are limits to coating technology, it may be more difficult to achieve a thicker ceramic layer while maintaining the ability of the ceramic layer to support a substrate that has been pre-bent without damaging the ceramic coating when the support is clamped to the fixture. The exact support strength and thermal conductivity of the ceramic can be determined by the composition of the ceramic. For example, a 2 mm coating of a ceramic based on zirconium dioxide stabilized by the addition of yttrium oxide can provide good mechanical support and good thermal insulation of the substrate without damaging the ceramic coating when the substrate is clamped to the fixture.

[0118] In an example, the mount system 100 can function as a shaping back structure. In an example, the mount system 100 can function as a support / shaping back structure. The mount system 100 can be positioned between a pre-bent substrate and a fixture when the pre-bent substrate is fixed to the fixture. In an example, after the DED manufacturing process is completed, after releasing the clamp that holds the substrate to the fixture, a self-balancing residual stress state can be achieved that allows for upward recovery (rebound) of the substrate and the DED structure built on the substrate. After the substrate is released from the clamp, it becomes straight.

[0119] In an example, the nominal deflection, h, provided by the mount system 100 mount(Arc degree), as shown in FIG. 2A, can be the difference between the maximum height at the center of the curved profile 102 and the upper surface of the edge or peripheral rim portion 104 of the curved profile 102, measured from the surface of the welding jig when the mounting system 100 is positioned on the welding jig. In FIG. 2A, the difference between the maximum height 198 of the curved profile 102 and the edge or peripheral rim portion 104 is h mount is. The length ratio L r and the surface area defined by the mounting system 100 is the ratio between the new x dimension L i of the surface area defined by the mounting system 100 and the original length L0 of the surface area defined by the mounting system 100. The predicted maximum deflection h Lr of the mounting system 100 is approximately proportional to the product of the nominal deflection h mount and the square of the length ratio L r of the surface area defined by the mounting system 100, which can be calculated according to the following formula: L r =L i / L0 Therefore, h Lr ≈h mount ×L r 2 .

[0120] Therefore, for example, in the case of a mounting system 100 that defines a surface area with xy dimensions of 635 mm × 190 mm (L × W), the predicted maximum deflection h Lr is approximately 3.8 mm. A more elongated surface area, such as one with xy dimensions of 1905 mm × 635 mm, has a length ratio of 3 (L r = 1905 / 635 = 3) and will have a maximum deflection h 2 ≈ 34.2 mm Lr . The nominal deflection can be from about 3 mm to about 35 mm. Thus, the amount of deflection can depend on the characteristics of the mounting system 100. The longer the mounting system 100 needs to be to accommodate a longer substrate, the higher / greater the deflection needs to be.

[0121] 1. Pin Support System and Pin In an example, the mount system 100 can include a pin support system 110. In an example, the pin support system 110 can include one or more pin structures or other solid standoff structures (referred to herein as "pins") 112. Examples of the mount system 100 implemented as a pin support system 110 having one or more pins 112 are shown in FIGS. 3A - 3M. In an example, the pin support system 110 can include a single pin 112. In an example, the pin support system 110 can include two or more pins 112. In an example, one or more pins 112 of the pin support system 110 may be disposed in engagement with the surface of a structure. In an example, one or more pins 112 of the pin support system 110 may be installed on a structure configured to be used in DED manufacturing. In an example, one or more pins 112 of the pin support system 110 may be disposed to engage a welding jig. In an example, one or more pins 112 of the pin support system 110 may be installed on the welding jig. In an example, one or more pins 112 of the pin support system 110 may be disposed on the welding jig.

[0122] In an example, implementing the mount system 100 as a pin support system 110 can provide one or more advantages. In an example, the pin support system 110 can be implemented while still achieving low thermal conductivity without using a ceramic sheet and / or a ceramic coating. In an example, the pin support system 110 can be implemented without using a ceramic sheet. In an example, the pin support system 110 may reduce costs. In an example, by using an array of pins 112, it may be possible to use less material than that required to form other types of support structures such as grids or molds. In an example, the pin support system 110 may exhibit an extended lifetime compared to other types of support structures.

[0123] In an example, the pin support system 110 can be reconfigurable. In an example, one or more pins 112 can be installed and reinstalled as desired. In an example, the pin support system 110 can be reconfigured for use with substrates of different sizes or pre-bent substrates. In an example, the pin support system 110 can include an array of pins 112 configured to be removably installed. In an example, the pin support system 110 can include an array of pins 112 that can be installed and reinstalled to achieve any desired arrangement. In an example, the reconfigurability of the pin support system 110 due to the flexibility in the arrangement of the array of pins 112 may lead to improved or more effective strain reduction when compared to other support structures such as grids or molds. In an example, the pins 112 can be arranged based on the design of the part to be manufactured. In an example, by arranging the pins 112 based on the design of the part to be manufactured, the user may be able to provide support at the locations where it is most needed to reduce strain.

[0124] In an example, the spacing between the pins 112 can be varied according to the desired support. In an example, the pins 112 may be arranged on a welding jig spaced 10 mm to 50 mm apart. In an example, the distance between two pins 112 can be 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, or 40 mm. These ranges and measurements are merely examples. In an example, all the pins 112 of the pin support system 110 can be equidistant from each other. In an example, the pins 112 of the pin support system 110 may not be equidistant from each other. In an example, two or more pins 112 of the pin support system 110 may be arranged closer to each other than two or more other pins 112 of the pin support system 110. Any combination or variation of these arrangements is also possible.

[0125] In an example, a pin support system 110 including one or more pins 112 may have an advantage compared to other types of support structures by providing an increased space or gap between a substrate or a pre-bent substrate and the surface of a welding jig. In an example, the pin support system 110 may be configured to occupy less space than other support structures because one or more pins 112 can be arranged only at desired support positions without an interconnecting structure spanning other regions. In an example, the pin support system 110 may provide flexibility to increase the space or gap between a substrate or a pre-bent substrate and the surface of a welding jig by employing one or more pins 112 having a large pin support height.

[0126] As previously explained, it may be possible to fill the gap or space formed between a substrate or a pre-bent substrate and a welding jig with the atmosphere of a DED chamber or a noble gas such as argon that can act as a thermal insulator. These gaps and spaces also provide a solid / gas / solid interface with a fairly low thermal conductivity. Therefore, these interfaces between the pre-bent substrate / argon gas / mounting system and / or welding jig can effectively function as a thermal barrier. Thus, in an example, one or more gaps or spaces can also help minimize the average heat transfer rate between a substrate or a pre-bent substrate and a welding jig. In an example, this helps maintain more heat in the pre-bent substrate, thereby further reducing a non-uniform temperature distribution and potentially reducing thermal stress in the pre-bent substrate.

[0127] In an example, one or more pins 112 of the pin support system 110 can be arranged to support a substrate or a pre-bent substrate at a position close to a clamp. In an example, one or more pins 112 of the pin support system 110 can be arranged to support a central region of a substrate or a pre-bent substrate. In an example, one or more pins 112 of the pin support system 110 can be arranged to support a central region of a substrate or a pre-bent substrate to prevent warping.

[0128] In an example, one or more clamps can be used to fix a preliminarily bent substrate to a jig. As a result, since the substrate or the preliminarily bent substrate is pressed toward the jig, the force required to fix the substrate or the preliminarily bent substrate to the jig exists between the clamp and the jig, and the pin support system 110 has one or more pins 112 as a support between the substrate or the preliminarily bent substrate and the welding jig. In an embodiment, the preliminarily bent substrate is pressed axially downward. In an example, the back side (the first side) of the preliminarily bent substrate where a melting track may exist can be positioned to face the pin support system 110. In this configuration, the back side of the preliminarily bent substrate faces downward toward the pin support system 110 and the jig. As described above, the preliminarily bent substrate can be fixed to the jig with one or more clamps with the pin support system 110 sandwiched between the preliminarily bent substrate and the jig.

[0129] In an example, the pins 112 of the pin support system 110 can be composed of any metal having sufficient strength and temperature resistance for use under typical conditions of DED processing as described above when considering the mount system 100. In an example, all the pins 112 of the pin support system 110 are made of the same material. In an example, the material of each pin 112 can be selected independently. In an example, at least a first pin of the plurality of pins includes the same material as at least a second pin of the plurality of pins of the pin support system 110. In an example, at least a first pin of the plurality of pins includes a material different from the material included in at least a second pin of the plurality of pins of the pin support system 110.

[0130] As described above, in the example, a ceramic sheet, plate, and coating are not used in the implementation of the mount system 100. In the example, the pin support system 110, one or more pins 112, or both do not include ceramics and / or a ceramic coating. In the example, the pin support system 110 may not include any ceramic sheet, plate, and pylon. In the example, if desired, one or more ceramic elements or coatings can be used in combination with the pin support system 110. In the example, one or more pins 112 may include a coating of ceramics and / or a bond coating as described above. In the example, a ceramic coating and / or a bond coating can be applied at least to the pin substrate contact surface 119. In the example, if one or more spacers 128 are ceramic spacers, ceramic-coated spacers, or a combination of both, one or more 128 can be employed as described herein. The types of ceramics, coating processes, and characteristics of the ceramic elements and / or coatings already considered are equally applicable to the implementation in the pin support system 110 and / or to the implementation on one or more pins 112.

[0131] In an example, the pin can have any desired shape and size that enables the functionality described herein. In an example, the pin 112 can have a shape that is generally long, spherical, cubic, trapezoidal, cylindrically disc-shaped, conical, round, angular, annular, non-spherical, regular, irregular, and any combination thereof. FIG. 3A shows some exemplary shapes of the pin 112. In an example, the pin 112 can include a long shape as shown overall. In an example, the pin 112 can have a cross-sectional diameter, width, or thickness that is uniform over the length of the pin or pin structure 112, as shown by samples 114a, 114b, and 114c for example. In an example, the pin can include a tapered profile, as shown by samples 115a, 115b, and 116c for example. In an example, the pin 112 can include one or more portions having a cross-sectional diameter, width, or thickness that is greater than the cross-sectional diameter, width, or thickness of at least one other portion of the pin 112, as shown by samples 115a, 115b, and 116a - 116f for example. In an example, the pin 112 can have a mushroom shape, as shown by samples 116a, 116b, 116d, 116e, 116f for example. In an example, one or more portions of the pin 112 can have a shape that is different from at least one other portion of the pin, as exemplified by samples 116a - 116f for example. In an example, one portion of the pin 112 can have a trapezoidal shape and a second portion can have a cylindrical shape, as shown by samples 116c, 116d, 116e, 116f for example. In an example, one portion of the pin 112 can have a spherical or hemispherical shape and a second portion can have a cylindrical shape, as shown by samples 116a and 116b for example. In an example, the pin 112 as shown can include a trapezoidal shape instead of a cylindrical shape. Any combination of two or more of the above-described shapes can be used for the shape of the pin 112. In an example, the pin 112 can include a conical shape as shown in FIG. 3B for example. In an example, as shown in FIG. 3B, the pin 112 can include a portion having a cylindrical shape and a portion having a conical shape.In an example, the conical shape can include a double conical shape oriented in opposite directions, as shown in FIG. 3B.

[0132] In an example, the pin 112 can include a pin head portion 118. In an example, the pin head portion 118 includes at least a portion of the pin 112 that is configured to remain exposed when the pin 112 is attached to a welding jig, i.e., it extends beyond the surface of the device to which the pin 112 is connected. In an example, the pin head portion 118 can have any shape or size. In an example, the pin head portion 118 can have a width or diameter in the range of 10 mm to 40 mm and a length in the range of 0.05 mm to 10 mm. These dimensions are merely examples. In an example, the pin head portion 118 can have the same or different shape and / or size as the base portion or engagement portion 124. In an example, as shown in FIG. 3B, the pin head portion 118 can include a double conical shape. In an example, the pin 112 can include a double conical shape to function as a dish screw or bolt to assist in achieving a flush fit in the same plane as the surface on which the pin 112 is installed. In an example, the pin head portion 118 of the pin 112 can be configured to lie flat on the surface of the welding jig when in contact with it.

[0133] In an example, the pin head portion 118 can include a substrate contact surface 119. In an example, the pin substrate contact surface 119 includes the surface area of the pin 112 configured to contact a substrate or a pre-bent substrate when the pin support system 110 is in use. The pin substrate contact surface 119 can have any desired size. In an example, the pin substrate contact surface 119 can occupy an area in the range of 2 15 mm 2 to 60 mm. This range is merely an example.

[0134] In an example, the pin substrate contact surface 119 can be flat, uneven, round, convex, concave, hollow, corrugated, knurled, or any combination thereof, as also shown in FIG. 3B. The corrugation and / or knurling of the pin substrate contact surface 119 can be achieved in the same manner as any other surface, as described previously in the context of the mounting system 100.

[0135] In an example, the area of the pin substrate contact surface 119 of the pin 112 can be the substrate contact area of the pin 112. In an example, the substrate contact area of the pin 112 may be adjusted or configured to be different from or less than the area of the pin substrate contact surface 119. In an example, the substrate contact area of the pin 112 may be a part or fraction of the area of the pin substrate contact surface 119 of the pin 112. In an example, the substrate contact area of the pin 112 configured to have a pin head substrate contact surface 119 with a surface profile or profile that is uneven, round, convex, concave, hollow, corrugated, knurled, or any combination thereof may be smaller than the area of the surface of the pin head substrate contact surface 119. In an example, when the pin head substrate contact surface 119 is a uniform, flat or planar surface, configured to be parallel to the surface of a welding jig facing the substrate or a preliminarily bent substrate during use, and the pin support system 110 is configured to contact the substrate or a preliminarily bent substrate when used as the mounting system 100, the substrate contact area of one pin 112 corresponds to the surface area of the pin head substrate contact surface 119. In an example, when the pin head substrate contact surface 119 is uneven, round, convex, concave, hollow, corrugated, knurled, i.e., not a uniform, flat or planar surface, and / or not configured to maintain parallelism with the surface of a welding jig facing the substrate or a preliminarily bent substrate during use, the substrate contact area of one pin 112 is smaller than the surface area of the pin head substrate contact surface 119. In this latter case, the substrate contact area of the pin 112 is only the portion of the surface area of the pin head substrate contact surface 119 configured to contact the substrate or a preliminarily bent substrate during use.

[0136] In an example, the pinhead portion 118 can include any lateral profile. In an example, the lateral profile of the pinhead portion 118 can be tapered, linear, stepped, regular, irregular, round, planar or flat, or any combination thereof. In an example, as shown in FIG. 3B, the pinhead portion 118 can include one or more flat regions 120. In an example, the one or more flat regions 120 can be disposed over at least a portion of the lateral profile of the pinhead portion 118. In an example, the flat region 120 may help with the attachment of the pin 112.

[0137] In an example, the pinhead portion 118 can be configured to be wider than the base portion 124. In an example, the pinhead portion 118 can include a wider pinhead portion 118 configured to contact the surface of the welding jig when the pin 112 is installed. This can allow for more support and improved resilience of the pin 112 when a substrate or a pre-bent substrate is pressed against the pin support system 110.

[0138] In an example, as shown in FIG. 3B, the pin head portion 118 may include an area 121 that can contact or otherwise interface with the surface of the welding jig to which the pin 112 is attached. In an example, the pin head portion 118 may include a welding jig interface area 121 at an end opposite from where the pin head substrate contact surface 119 is located. The interface between the pin head portion 118 and the surface of the welding jig may be affected by the contour of the surface of the pin head portion 118 configured to face the surface of the welding jig when the pin 112 is attached to the welding jig. In an example, the pin head portion 118 may be configured to have a flat, planar, or tapered profile along the surface 121 intended to interface with the welding jig. In an example, the surface 121 is flat and configured to be horizontal with respect to the surface of the welding jig when the pin 112 is attached. In an example, the surface 121 may be configured such that the pin head portion 118 can be laid flat on the jig when the pin 112 is attached. In an example, the surface 121 of the pin head portion 118 intended to interface with the welding jig may be configured to have a rough, round, irregular shape and / or may be knurled, corrugated, or may include ridges, valleys or similar features as described with respect to the pin substrate contact area 119. In an example, having a smooth or more conformable profile in the area 121 of the pin head portion 118 configured to interface with the welding jig may provide for a coplanar installation. In an example, having a non-smooth, rough, corrugated, or knurled profile in the area 121 of the pin head portion 118 configured to interface with the welding jig may provide an additional barrier to heat transfer from the pin 112 to the welding jig and indirect heat transfer from the substrate or pre-bent substrate to the welding jig. In an example, the welding jig interface area 121 of all the pins 112 of the pin support system 110 can define the side of the pin support system 110.

[0139] In an example, pin 112 may include a color portion 122 located between the pin head portion 118 and the pin base portion 124. In an example, the color portion 122 may be below, proximate to, and / or overlap with the welding jig interface area 121. In an example, the color portion 122 may have any desired size and / or profile. In an example, the color portion 122 may have a width or diameter different from that of the pin base portion 124, the pin head portion 118, or both. In an example, the color portion 122 may have a width or diameter in the range of 2 mm to 10 mm and a length in the range of 5 mm to 10 mm. These size ranges are merely examples. In an example, as shown in FIG. 3C, the color portion 122 may be configured to accommodate one or more pin spacers 128 to provide support between the pin head portion 118 and the surface of the welding jig on which the pin 112 is installed and / or to add thermal insulation. In an example, the pin spacer 128 may be configured in any size and shape that can fit the color portion 122. In an example, the pin spacer 128 may include a washer, a ring, a plate, or a similar structure. In an example, the pin spacer 128 may include a metal or a similar material as described for the pin or structure 112 or as used in the mounting system 100. In an example, the pin spacer 128 may include a ceramic as described herein. In an example, the pin spacer 128 may include both metal and ceramic.

[0140] In an example, pin 112 may include a base portion or an engagement portion 124. In an example, the base portion or the engagement portion 124 may refer to a portion of the pin 112 configured to engage an opening, a joint, a bore, or a threaded hole of a device to which the pin 112 is connected. In an example, the base portion or the engagement portion 124 may be configured to have any desired shape and size. In an example, the base portion or the engagement portion 124 may have a width or diameter in the range of 2 mm to 10 mm and a length in the range of 10 mm to 50 mm. These size ranges are merely examples. In an example, the base portion or the engagement portion 124 of the pin 112 may be configured to engage a welding jig. In an example, the base portion or the engagement portion 124 may be configured to removably engage a structure. In an example, the base portion or the engagement portion 124 may be configured to be removably engaged with a welding jig.

[0141] To enable the installation of the pin 112 on the welding jig, any suitable means for engaging the base portion or the engagement portion 124 with the welding jig can be employed. In an example, the base portion or the engagement portion 124 may be configured as a bearing, a screw, a bolt, or a similar structure. In an example, the welding jig can provide a suitable opening, joint, bore, threaded hole, or a similar structure for engaging the base portion or the engagement portion 124. In an example, the base portion or the engagement portion 124 may be detachable from one or more of a plurality of openings, joints, bores, threaded holes, or similar structures provided in the welding jig. In an example, the base portion or the engagement portion 124 may be configured to permanently engage a joint, a bore, or a threaded hole, or a similar structure provided in the welding jig.

[0142] An example of installing the pin 112 on the welding jig 400 is shown in FIG. 3C. As shown, the welding jig 400 may include a bore 126 configured to receive the base portion or the engagement portion 124. Also as shown, when the pin 112 is installed, the pin head portion 118 may extend from the surface of the welding jig 400 while remaining exposed.

[0143] In an example, the base portion or the engagement portion 124 can engage directly with the welding jig, engage with any structure attached to the surface of the welding jig, or engage with any combination thereof. Thereby, flexibility is obtained to install one or more pins 112 on any contour. The engagement of the pin 112 with the structure provided on the surface of the welding jig can be performed in the manner described with respect to the welding jig. In an example, the added structure can include one or more openings, joints, bores, or screw holes or joints on one or more of its surfaces. In an example, the bore of the joint can be configured similar to the bore or screw hole structure 126 of the welding jig 400.

[0144] In an example, the pin 112 can be configured to adjust the distance between the surface of the welding jig and a portion of the pin head substrate contact surface 119 configured to physically contact the substrate or the pre-bent substrate during use. For the purposes of this description, the perpendicular straight-line distance between the surface of the welding jig facing the substrate or the pre-bent substrate during use and the said portion of the pin substrate contact surface 119 configured to physically contact the substrate or the pre-bent substrate during use is referred to as the "pin support height" (h pin support ) as shown in FIG. 3D.

[0145] In an example, the pin 112 can be configured to allow adjustment of the pin support height regardless of the degree of engagement by the base portion or the engagement portion 124. In an example, the pin 112 can be configured to have a telescoping portion. The adjustable portion can be the base portion or the engagement portion 124, the pin head portion 118, or both. In an example, a portion of the pin 112 can be configured to slide in and out of another portion of the pin 112. In an example, a part of the pin 112 can include a threaded bearing that can extend and retract the pin 112 by rotating a first end of the threaded bearing relative to a second end of the threaded bearing. In an example, the base portion or the engagement portion 124 of the pin 112 can be configured to engage the joint at various depths. In an example, the base portion or the engagement portion 124 of the pin 112 can be configured to include an extended thread for fixing the pin to the threaded joint of the welding jig at various depths. In an example, as shown in FIG. 3D, when the base portion or the engagement portion 124 of the pin or the structure 112 is rotated in the clockwise direction, it can move through the threaded joint in a first longitudinal direction and bring the pin head portion 118 closer to the surface of the welding jig. Conversely, in an example, when the base portion or the engagement portion 124 of the pin or the structure 112 is rotated counterclockwise, it can move through the threaded joint in a second longitudinal direction opposite to the first longitudinal direction and move the pin head portion 118 away from the surface of the welding jig. In an example, the pin support height can be adjusted by translating the pin head portion 118 towards and away from the surface of the welding jig. In an example, one or more spacers 128 can be employed when adjusting the pin support height. In an example, one or more spacers 128 can be introduced between the pin head portion 118 and the surface of the welding jig facing the pin head portion 118 as described above. In an example, one or more spacers 128 can be washers or similar structures configured to fit around the collar 122 of the pin 112.In an example, as shown in, for example, FIG. 3C, by disposing one or more spacers 128 between the pin head portion 118 and the surface of the welding jig, the pin head portion 118 is positioned at a position further away from the surface of the welding jig, and as a result, the pin support height may increase. In an example, when removing one or more spacers 128 from the space between the pin head portion 118 and the welding jig surface, the pin head portion 118 is positioned closer to the welding jig surface, and as a result, the pin support height may decrease. In an example, different numbers of spacers 128 can be used for different pins 112 to achieve different pin support heights across the entire array of pins 112. In an example, the spacer 128 can provide additional stability and / or support to the pin head portion 118 by filling the space between the pin welding jig interface area 121 and the surface of the welding jig. In an example, the spacer 128 can also assist in implementing a uniform pin support height and / or adjusting the pin support height. In an example, any combination of the above-described pin support height adjustment methods can be used.

[0146] In an example, as shown in FIG. 3D, the pin support height of the pin 112 may depend on the size of the pin 112 or the size of any part of the pin 112. In an example, as shown in FIG. 3D, different pins 112 employed in the pin support system 110 may have different sizes and thus different pin support heights.

[0147] In an example, the mounting system 100 can be implemented using the pin support system 110 by installing one or more pins 112 on the welding jig 400 and / or one or more structures provided on the welding jig 400. In an example, the pin support system 110 may include an array of pins 112. The array can be two or more pins.

[0148] a. Pin Support System with Multiple Pins In an example, the pin support system 110 may include an array of two or more pins 112. In an example, the array of two or more pins 112 may be disposed on the surface of a structure such as a welding jig as described above. In an example, the pin support system 110 can include any number of pins 112. In an example, the total number of pins 112 within the pin support system can be limited by the size of the pins 112, the size of the substrate or pre-bent substrate that the pin support system 110 is configured to contact, or a combination of both. Each of the two or more pins 112 can also have any desired size. In an example, the size of one or more pins 112 can be limited by the number of pins employed, the size of the substrate or pre-bent substrate that the pin support system 110 is configured to contact, or a combination of both.

[0149] The pin support system 110 can be configured to include a predetermined substrate contact interface. In an example, the size and number of pins 112 affect the total substrate contact area of the pin support system 110 and thus, as described above, can affect the substrate contact interface of the pin support system 110. For the purpose of the substrate contact interface of the pin support system 110, the substrate interface area can be understood to be the substrate interface area 130 as described. In an example, the pin support system 110 can be configured to have an array of pins 112 arranged and configured to provide a controlled substrate contact interface that falls within the range of 0.1 to 20. In an example, the substrate interface of the pin support system 110 with respect to a given substrate interface area 130 can be defined by the number of pins 112, the size of the substrate contact area of the pins 112, or a combination of both. In an example, the pin support system 110 can provide increased flexibility in controlling the substrate contact interface by adding or removing pins 112 and / or by replacing one or more pins 112 with one or more pins 112 having different sized substrate contact areas.

[0150] In an example, the pin support system 110 can be configured to include a substrate contact interface that is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 or greater and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or less. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.2 to 20, 0.2 to 15, 0.2 to 10, 0.2 to 5, or 0.2 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.3 to 20, 0.3 to 15, 0.3 to 10, 0.3 to 5, or 0.3 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.5 to 20, 0.5 to 15, 0.5 to 10, 0.5 to 5, or 0.5 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.6 to 20, 0.6 to 15, 0.6 to 10, 0.6 to 5, or 0.6 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.7 to 20, 0.7 to 15, 0.7 to 10, 0.7 to 5, or 0.7 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.8 to 20, 0.8 to 15, 0.8 to 10, 0.8 to 5, or 0.8 to 1. In an example, the pin support system 110 can be configured to have a substrate contact interface in the range of 0.9 to 20, 0.9 to 15, 0.9 to 10, 0.9 to 5, or 0.9 to 1.

[0151] In an example, the pin support system 110 can be configured to include a first side 111 and a second side defined by one or more pins 112. In an example, the first side of the pin support system 110 can correspond to the side where one or more pins 112 interface with a welding fixture. In an example, one or more pins 112 can define a curved profile 102 as described above. In an example, the curved profile 102 can be on the second side 113 of the pin support system 110 opposite the first side. In an example, the second side 113 is also the side where the substrate contact interface 130 of the pin support system 110 is provided or defined. In an example, the curved profile 102 can be defined by one or more pins 112 on the side of the pin support system 110 configured to face a substrate or a pre-bent substrate during use. In an example, when the pin support system 110 includes two or more pins 112, the curved profile 102 can be a plane defined by the distal ends of the two or more pins 112 as considered with reference to FIG. 2A where the two or more pins 112 are represented by an element or structure 101. In an example, the distal ends of the pins 112 for the purpose of defining the curved profile of FIG. 2A can include at least a portion of the pin substrate contact surface 119 configured to physically contact a substrate or a pre-bent substrate during use. In an example, the area of the mount system 100 configured to receive a substrate or a pre-bent substrate when the mount system 100 is implemented as the pin support system 110 can be defined by one or more pins or pin structures 112 arranged to define a peripheral region of the pattern when installed on a welding fixture.

[0152] In an example, it may be possible to arrange one or more pins 112 in any desired manner. In an example, the one or more pins 112 may be configured to be arranged to have varying pin support heights. In an example, at least one or more pins 112 may be configured to have a pin support height greater than the pin support height of at least one other pin 112. In an example, the pin support height of one pin 112 may be distinguished from the pin support height of at least one other pin 112 by using pins 112 configured to have an adjustable pin support height as described above, by using pins 112 having different sizes, or by a combination of both.

[0153] In an example, two or more pins 112 of the pin support system 110 can be arranged to define the curved profile 102 as described above. In an example, the pin support system 110 can be configured to include one or more pins 112 having a first pin support height disposed on a welding jig at a first position and one or more pins 112 having a second pin support height disposed on the welding jig at a second position. In an example, the first pin support height is different from the second pin support height. In an example, the first pin support height is smaller than the second pin support height. In an example, one or more pins 112 having a smaller pin support height are arranged to surround one or more pins 112 having a larger pin support height. In an example, the pin support system 110 can include one or more pins having a third pin support height. The third pin support height can be different from the first and second pin support heights. In an example, the pin support system 110 can include any number of one or more pins 112 having different pin support heights. In an example, the pin support system 110 may include an array of pins 112 arranged in a pattern, and one or more pins 112 located in the peripheral region of the pattern have a pin support height smaller than the pin support height of one or more pins 112 located in the central region of the pattern. In an example, the pin support system 110 can include an array of pins 112 arranged in a pattern such that the pin support height gradually increases from the peripheral region of the pattern towards the central region of the pattern. In an example, by gradually increasing the pin support height towards the central region of the pattern of the arranged pins 112, a curved profile 102 can be defined that can clamp a substrate or a preliminarily bent substrate.

[0154] Figures 3E - 3H illustrate an exemplary implementation of the pin support system 110 as the aforementioned mount system 100. Figures 3E and 3F show top views of an example of the pin support system 110 including an array of pins 112 arranged to define a substrate interface area 130. In the example, the substrate interface area of the pin support system 110 is larger than the physical surface area of the pin support system 110 configured to face the substrate or a pre - bent substrate when the pin support system 110 is in use. In the example, the physical surface area of the pin support system 110 is limited to the surfaces of one or more pins 112 that make up the pin support system 110, while the substrate interface area 130 is understood to be the area on one side of the support system 110 that is intended to be occupied by the substrate or a pre - bent substrate when the pin support system 110 is in use. In the example, as shown, one or more pins 112 that are part of the pin support system 110 can be arranged to delineate the perimeter or boundary of the substrate interface area 130 intended for the pin support system 110. In the example, it may be possible to reconfigure the boundary of the substrate interface area 130 of the pin support system 110 by re - arranging one or more pins 112. In the example, one or more pins 112 of the pin support system 110 that define the boundary of the substrate interface area 130 can be one or more pins 112 located at the periphery of a set or cluster of one or more pins 112. In the example, the pins 112 in the peripheral region of the substrate interface area 130 may be close to the location where the clamp 500 is to be placed. Thereby, it may be possible to clamp the substrate or a pre - bent substrate when the pin system 110 is in use. In the example, the pins 112 may also be arranged in a central region to support the central portion of the substrate or a pre - bent substrate 300. In the example, the pins 112 at the position closest to the clamp 500 may have a pin support height that is less than or adjusted to have a pin support height than the pin support height of the pins 112 located in the central portion of the substrate interface area 130.As shown in FIGS. 3E and 3F, pins 112 of the pin support system 110 can be provided in different numbers, different arrangements, different spacings, or any combination thereof to accommodate substrates of different sizes or substrates that have been preliminarily bent.

[0155] In an example, the curvature profile achieved by one or more pins 112 of the pin support system 110 can be similar to the curvature profile of an integral structure such as a grating or mold structure described below. In an example, when measured from the surface of the welding jig, one or more pins 112 are arranged to define a curvature profile 102 having a height measured at or near the center of the curvature profile 102 in the range of about 3 mm to about 60 mm, or about 12 mm to about 50 mm, or about 15 mm to about 45 mm, and their pin support heights can be adjusted or selected. Similarly, one or more pins 112 of the pin support system 110 can be selected and / or adjusted to have a pin support height such that the height of the curvature profile measured from the surface of the welding jig facing the substrate preliminarily bent during use is in the range of about 0.5 mm to about 55 mm, or about 3 mm to about 45 mm, or about 10 mm to about 40 mm at or near the outer edge of the curvature profile 102. In an example, when viewed from the side, the thickness profile of the curvature profile defined by one or more pins 112 of the pin support system 110 has a maximum height at the center of the curvature profile, at the center of the substrate interface area 130 defined by one or more pins 112, or both, and the height can gradually decrease towards the outer edge or periphery of the substrate interface area 130 of the curved surface. In an example, the difference in height across the cross-section of the pin support system 100 may result in a concave downward curve. In the cross-section viewed from the side, the shape of the curvature profile defined by the pin support system 110 may resemble the upper half of an ellipse with a minor axis much smaller than its major axis. The ellipse can have an eccentricity close to 1 but less than 1 (an eccentricity of 1 is a flat surface).

[0156] Figures 3G and 3H show schematic side views of a pin support system 110 that includes an array of pins 112 in use, provided on a welding jig 400 having a substrate 300 clamped thereon by a clamp 500 or a pre-bent substrate 300. As shown in Figures 3G and 3H, the pin support system 110 can be implemented using various numbers of pins 112. Figure 3I shows additional examples of pins 112 having different shapes and sizes that can be used in the pin support system 110.

[0157] Figures 3J - 3M show schematic cross - sectional side views of a DED manufacturing process using a pin - support system 110 as the mount system 100. In an example, the clamp 500 can be disposed along the entire circumference of the substrate or pre - bent substrate 300. In the figures, the clamps 500 are shown only at the ends, for the reason that this is a cross - sectional side view to show the pin - support system 110 that would otherwise be covered by the pre - bent substrate 300 and the clamps 500. As shown in FIG. 3J, the pre - bent substrate 300 can be clamped onto the pin - support system 110 that includes one or more pins 112 disposed on the welding jig 400 using the clamps 500. As shown in FIG. 3J, the array of pins 112 of the pin - support system 110 can be configured and arranged to provide a curved profile on which the substrate or pre - bent substrate 300 is disposed. In an example, one or more clamps 500 can apply sufficient pressure to the substrate or pre - bent substrate to conform the substrate or pre - bent substrate to the curved profile defined by the array of pins 112. The pre - bent substrate 300 can then be heat - treated as shown in FIG. 3K. In an example, after heat - treatment, the DED manufacturing can proceed as shown in FIG. 3L while depositing one or more layers using a deposition device, such as a plasma arc torch 250. When the deposition process is complete, the clamps 500 can be removed as shown in FIG. 3M. As shown, by using the pin - support system 110 as the mount system 100 in combination with a strain - reduction process as described herein, the resulting workpiece is expected to have an improved profile.

[0158] As previously described for the mount system 100, in an example, the nominal deflection, h, provided by the pin - support system 110 pin support(Arc degree) can be the difference between the maximum height at the center of the curved profile 102 and the upper surface of the edge or peripheral rim portion 104 of the curved profile 102, measured from the surface of the welding jig when the pin support system 110 is positioned on the welding jig, as shown in Figure 2A. In Figure 2A, the difference between the maximum height 198 of the curved profile 102 and the edge or peripheral rim portion 104 is h pin support is. The length ratio L r and the surface interface area 130 defined by the pin support system 110 is the ratio between the new x dimension L i of the surface area defined by the pin support system 110 and the original length L0 of the surface area defined by the pin support system 110. The predicted maximum deflection h Lr of the pin support system 110 is approximately proportional to the product of the nominal deflection h pin support and the square of the length ratio L r of the surface area defined by the pin support system 110, and this can be calculated according to the following formula: L r =L i / L0 Therefore, h Lr ≈h pin support ×L r 2 .

[0159] Therefore, for example, in the case of a pin support system 110 that defines a surface interface area 130 with xy dimensions of 635 mm × 190 mm (L × W), the predicted maximum deflection h Lr is approximately 3.8 mm. A more longitudinally defined surface area, such as one with xy dimensions of 1905 mm × 635 mm, has a length ratio of 3 (L r = 1905 / 635 = 3), and a maximum deflection h 2 of 3.8 × 3 Lrwould have. The nominal deflection can be from about 3 mm to about 35 mm. Thus, the amount of deflection can depend on the characteristics of the pin support system 110. The longer the surface interface area 130 defined by the pin support system 110 needs to be to accommodate a longer substrate, the higher / greater the deflection needs to be.

[0160] b. Pin support system by a single pin In an example, the mount system 100 can be implemented as a pin support system 110 with a single pin. In an example, the pin support system with a single pin can include a single pin 112 as described. In an example, when the pin support system 110 is a pin support system with a single pin, the pin support system 110 can include a first side that interfaces with or faces a welding jig as described for the pin 112 during installation, and a second side that has or defines a curved profile 102. In an example, the curved profile 102 can be the profile of the upper surface of the single pin 112. In an example, when the pin support system 110 is a single pin, the pin can be configured to include a curved physically modified surface that is oriented in a direction away from the jig when installed in the jig, as described with respect to the curved clamp mold 170 described below. The pin of the pin support system with a single pin can include a pin head 118 having a central portion that is thicker than the edges, including dimensions as described with respect to the clamp mold 170. Also, similar to the clamp mold 170, the pin used in the pin support system with a single pin can include a first side having a peripheral rim. In an example, the peripheral rim can have a flat or planar surface on at least one side. In an example, as considered for the clamp mold 170, for the pin support system with a single pin, the pin can be configured to include a structure having a surface contact interface that falls within the range of 0.1 to 20 or any sub-range thereof as described. Also, similar to the description of the curved clamp mold 170, the pin support system 110 with a single pin can include one or more ceramic coatings and / or bond coatings and exhibit the same or similar nominal deflection as described for the curved clamp mold 170.

[0161] 2. Lattice Support Structure In an example, the mount system 100 can include a lattice support structure 150. Examples of the lattice support structure 150 are shown in FIGS. 4A - 4D. In an example, the lattice support structure 150 can include a framework or structure of one or more metal elements 151. In an example, the lattice support structure 150 can be a frame.

[0162] In an example, the metal element 151 can have any desired shape and size. In an example, the metal element can be long, spherical, cubic, trapezoidal, and can have regular or irregular shapes, and any combination thereof. In an example, the metal elements 151 of the lattice support structure 150 include strips, rods, bars, or similar structures. As shown in the schematic perspective view provided in FIG. 4A, the plan view of FIG. 4B, and the side view of FIG. 4C of the lattice support structure 150, the metal elements 151 can have uniform shapes and sizes, different shapes and sizes, and any combination thereof.

[0163] In an example, the metal elements 151 constituting the lattice support structure 150 can have any arrangement. As shown, the metal elements 151 are perpendicular and parallel to each other. In an example, the metal elements 151 may be oblique to each other or randomly arranged. The metal elements 151 may be connected to each other by any known fasteners such as bolts, screws, brackets, pins, bearings, or similar structures. In an example, the metal elements 151 may be attached to each other by welding, fusing, or an adhesive. In an example, all of the metal elements 151 can be part of one integral continuous structure. In an example, the lattice support structure 150 can include any one or more of the above-described arrangements of the metal elements 151 connected to each other in any one or more of the described manners and / or as part of a continuous integral structure.

[0164] The grid support structure 150 can be configured to include a predetermined substrate contact interface. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.1 to 20. In an example, the grid support structure 150 can be configured to include a substrate contact interface that is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 or more, and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or less. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.2 to 20, 0.2 to 15, 0.2 to 10, 0.2 to 5, or 0.2 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.3 to 20, 0.3 to 15, 0.3 to 10, 0.3 to 5, 0.3 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.4 to 20, 0.4 to 15, 0.4 to 10, 0.4 to 5, or 0.4 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.5 to 20, 0.5 to 15, 0.5 to 10, 0.5 to 5, or 0.5 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.6 to 20, 0.6 to 15, 0.6 to 10, 0.6 to 5, or 0.6 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.7 to 20, 0.7 to 15, 0.7 to 10, 0.7 to 5, or 0.7 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.8 to 20, 0.8 to 15, 0.8 to 10, 0.8 to 5, or 0.8 to 1. In an example, the grid support structure 150 can be configured to have a substrate contact interface in the range of 0.9 to 20, 0.9 to 15, 0.9 to 10, 0.9 to 5, or 0.9 to 1.

[0165] In an example, the lattice support structure 150 may include a peripheral region 154 as shown that defines a boundary of a substrate interface area 155 (represented by a dashed line) of the lattice support structure 150. In an example, the substrate interface area of the lattice support structure 150 may be different from, for example, smaller than, the surface area defined by the peripheral region 154. As described above, the substrate interface area should be understood as an area configured to be overlapped by a substrate or a preliminarily bent substrate when the lattice support structure 150 is being used.

[0166] In an example, the substrate contact interface of the grid support structure 150 with respect to a given substrate interface area can be controlled by the configuration of the metal elements that define the substrate contact surface of the grid support structure 150. In an example, the grid support structure 150 can be configured to have one or more sizes and a greater or lesser number of metal elements at various intervals and at various angles across a surface configured to interface with a substrate or a pre-bent substrate. By controlling the number, size, and spacing of the metal elements of the grid support structure 150 intended to contact the substrate or the pre-bent substrate during use, it may be possible to affect the overall substrate contact area of the grid support structure 150. In an example, the substrate contact area of one or more elements of the grid support structure 150 may be affected. In an example, the substrate contact surface of one or more elements 151 of the grid support structure 150 is configured to be uneven, angular, round, concave, convex, irregular, planar, non-planar, or any combination thereof. For example, as shown in FIGS. 4A-4B, the metal element 151 can have a tapered profile that defines an element substrate contact surface 156 that is narrower than the full width of the element. In an example, the narrower element substrate contact surface 156 can result in a reduction of the substrate contact area. In an example, the area of the element substrate contact surface 156 may be equal to its element substrate contact area. In an example, the substrate contact area of the element substrate contact surface 156 of one or more elements 151 of the grid support structure 150 may be smaller than the area of the element substrate contact surface 156. In an example, the element substrate contact surface 156 may be knurled, corrugated, or otherwise include ridges and valleys as described herein. In an example, these surface effects can reduce the substrate contact area of the substrate contact surface 156 of the element 151 by preventing the substrate or the pre-bent substrate from fully contacting the substrate contact surface 156 of the element 151. In an example, the substrate contact surface 156 of one or more elements of the grid support structure 150 can include one or more protrusions configured to space apart the surface of the clamped substrate or the pre-bent substrate from one or more portions of the substrate contact surface 156 of the element 151.Adopting any of these surface effects on the surface contact area of one or more elements of the lattice support structure 150 can affect the substrate contact area and thus the substrate contact interface of the lattice support structure 150.

[0167] In an example, the lattice support structure 150 may include one or more cavities 158 that can form one or more void areas within the lattice support structure 150. As previously explained, it may be possible to fill the gaps or voids with the atmosphere of the DED chamber or a noble gas such as argon that can act as a thermal insulator. Also, these gaps and voids provide a solid / gas / solid interface with a fairly low thermal conductivity. Thus, these interfaces between the pre-bent substrate / argon gas / mounting system and / or welding jig may effectively function as a thermal barrier. Thus, in an example, one or more gaps or voids may also help to minimize the average heat transfer rate between the substrate or pre-bent substrate and the welding jig. In an example, this may help to maintain more heat within the pre-bent substrate, thereby further reducing the non-uniform temperature distribution and potentially reducing the thermal stress within the pre-bent substrate.

[0168] In an example, the lattice support structure 150 can provide the advantage of including a design that requires a reduced amount of material for fabrication. This is cost-effective while still maintaining the physical stability of the integral self-supporting structure. In addition to the cost reduction achieved by reducing the amount of non-magnetic metal required for fabrication, the lattice configuration of the lattice support structure 150 at the interface with the welding jig can limit the surface contact area between the lattice support structure 150 and the welding jig. In an example, the lattice support structure 150 can be configured to contact the welding jig only at one or more elements 151 of the lattice structure that define the interface between the lattice support structure 150 and the welding jig. In an example, the contact interface between the lattice support structure 150 and the welding jig can be configured as desired in the same way that the substrate contact interface of the lattice support structure 150 can be configured as described above. In an example, the lattice support structure 150 can be configured to include one or more elements 151 configured to engage the surface of the welding jig. For example, the one or more elements 151 can be configured as protrusions, as shown, for example, in FIGS. 4A, 4C, and 4D. In an example, the protruding element 151 can be configured to fit with one or more joints, openings, bores, or similar structures provided in the welding jig. In an example, the reduction in the contact interface with the welding jig can reduce the conductive heat transfer from the lattice support structure 150 to the jig while maintaining rigidity. This reduction in heat transfer can also contribute to the heat retention of the pre-bent substrate and may minimize losses to the welding jig.

[0169] In an example, the grid support structure 150 can define a first, generally planar, smooth, or flat side 153 configured to face a welding jig, as shown by the dashed line in FIG. 4C for example. In an example, the grid support structure 150 can define a second side having a curved profile (the "curved side") 152. The curved side 152 of the grid support structure 150 is directed away from the jig and toward the pre-bent substrate and can be positioned relative to the pre-bent substrate. The grid support structure 150 can also include a peripheral region 154. One or more clamps can be used to secure the pre-bent substrate to the jig. As a result, the substrate or the pre-bent substrate can be pressed toward the jig, so that the force required to secure the substrate or the pre-bent substrate to the jig is applied between the clamp and the jig, where the grid support structure 150 serves as a support between the substrate and the jig. In an embodiment, the pre-bent substrate is pushed axially downward.

[0170] In an example, the back side (the first side) of the pre-bent substrate where a molten track can be present can be positioned to face the side of the grid support structure 150 (the side facing away from the jig (the second side)). In this configuration, the back side of the pre-bent substrate faces downward toward the curved surface of the grid support structure 150 and the jig. As described above, with the grid support structure 150 sandwiched between the pre-bent substrate and the jig, one or more clamps can secure the pre-bent substrate to the jig.

[0171] The lattice support structure 150 can be configured to be thicker in the central portion than at the edges, such that the curved surface has a maximum height near its center. In the embodiments provided herein, the height of the lattice support structure 150 measured at or near the central portion of the lattice support structure 150 can range from about 3 mm to about 60 mm, or from about 12 mm to about 50 mm, or from about 15 mm to about 45 mm. The height of the lattice support structure 150 measured at or near the outer edge of the lattice support structure 150 can range from about 0.5 mm to about 55 mm, or from about 3 mm to about 45 mm, or from about 10 mm to about 40 mm. In an example, the thickness profile of the lattice support structure 150 when viewed from the side can have a maximum height at the center of the lattice support structure 150, and the height can gradually decrease towards the outer edge of the curved surface. In an example, the difference in height across the cross-section of the lattice support structure 150 can result in a concave downward curvature on the upper surface of the lattice support structure 150. In a cross-section viewed from the side, the shape of the lattice support structure 150 can resemble the upper half of an ellipse where the semi-minor axis is much smaller than the semi-major axis. The ellipse can have an eccentricity close to 1 but less than 1 (an eccentricity of 1 is a flat surface).

[0172] As described above, the lattice support structure 150 can be composed of any metal having sufficient strength and temperature resistance to be used under typical conditions of DED processing. In an example, one or more elements of the lattice support structure 150 can include the same or different materials as at least one other element of the lattice support structure 150.

[0173] As described above, in an example, in the implementation of the mount system 100, a ceramic sheet, plate, or pylon and / or a ceramic coating are not used. In an example, the lattice support structure 150 does not include a ceramic sheet or pylon, a ceramic coating, or both. In an example, the lattice support structure 150 can include a ceramic coating as described. In an example, the lattice support structure 150 can use a ceramic sheet, plate, or pylon.

[0174] In an example, the thickness of the lattice support structure 150 can be designed to mimic or provide the same or similar thermal insulation properties achieved by ceramic insulation sheets conventionally used in the DED process. For example, one or more sheets or plates of alumina (Al2O3) insulation are used in a conventional DED process to thermally isolate the substrate from a clamping fixed platform such as a jig. The conventional use of insulation sheets reduces the risk of potential thermal damage to the jig and at the same time contributes to a more uniform temperature distribution during the DED process. The thickness of the sheet or plate can vary, but the thickness of the conventionally used sheet can be about 3 mm to 3.5 mm. In a conventional DED process, multiple ceramic insulation sheets can be used. For example, in some conventional processes, about 4 ceramic insulation sheets or plates are used to provide an insulation layer of about 12 mm. More or fewer ceramic insulation sheets can be used in the conventional method. These alumina insulation plates can be cut to size. However, doing so releases alumina particles, which can cause inflammation in the respiratory tract and eyes. Also, alumina insulation sheets tend to be hygroscopic and can initially release water vapor during the heating temperature of the DED process, so the deposition environment can vary during processing, which is not desirable. Also, the conventionally used ceramic insulation sheets between the substrate and the jig are brittle and easily broken, so they must be discarded after use and thus become consumables that increase the cost of DED manufacturing.

[0175] In an example, the lattice support structure 150 can be used in combination with a conventional ceramic insulating plate. The lattice support structure 150 can replace the conventional ceramic insulating plate and can provide similar thermal insulation while maintaining the same height, so that the changes to the settings of the melting tool providing the heat source or the CAD-CAM path plan defining the piece manufactured by DED are minimal. As described above, there are no physical limitations on the thickness of the lattice support structure 150 other than the operation constraints depending on the machine. For example, the height stroke of the DED system can define the thickness of the lattice support structure 150 used. The thickness of the lattice support structure 150 can be selected to maximize the reduction of heat flow at the lattice support / jig interface while allowing sufficient clearance for the manufacture of the workpiece based on the height stroke of the system.

[0176] In an example, the lattice support structure 150 can include a ceramic coating. For example, a ceramic coating can be applied to the surface of the lattice support structure 150 facing the DED substrate. As described above, the ceramic coating can be applied directly to the curved surface, or the ceramic coating can be applied to a bond coat that is directly applied to the second curved surface. The ceramic coating can be applied directly to any surface of the lattice support structure 150 regardless of the presence or absence of a bond coat. In an example, the ceramic coating can provide thermal insulation to minimize or prevent thermal contact between the lattice support structure 150 and the substrate or the pre-bent substrate.

[0177] The process and characteristics of the ceramic coating applicable to the mount system 100 have been described above, and are similarly applicable to the lattice support structure 150. Also, as described above, in an example, the mount system 100 can include a bond coat. Similarly, in an example, the lattice support structure 150 can include a bond coat as described above.

[0178] In an example, the mount system 100 may include a wavy surface and / or a knurled surface. Similarly, in an example, to further minimize or prevent heat conduction between the lattice support structure 150 and the pre-bent substrate, the curved surface of the lattice support structure 150 can be defined and the portion of the lattice support structure 150 that physically contacts the substrate and / or the pre-bent substrate during use can be physically modified.

[0179] A knurled surface can be cut into a portion of the lattice support structure 150 configured to contact the substrate or the pre-bent substrate during use. The knurled surface can be cut before applying the ceramic coating layer. A wavy surface including a combination of ridges and valleys can be cut before applying the ceramic coating layer. A wavy surface including a combination of ridges and valleys in which the surface of one or more ridges has a knurled surface can be cut before applying the ceramic coating layer.

[0180] In an example, the surface of the lattice support structure 150 configured to contact the substrate or the pre-bent substrate during use may include knurling. The knurled surface of the surface of the lattice support structure 150 can be manufactured as described previously with respect to the mount system 100.

[0181] In an example, the surface of the lattice support structure 150 configured to contact the substrate or the pre-bent substrate during use can include a waveform or be processed into a waveform. In an example, the wavy surface may include alternating ridges and grooves. The waveform can extend along the length or width of one or more elements that make up the surface of the lattice of the lattice support structure 150 configured to contact the substrate or the pre-bent substrate during use. The ridges can be columns and can have the same characteristics and advantages as described previously.

[0182] As also described in the case of the mount system 100, the knurled pattern or waveform on the surface of the lattice support structure 150 can have a ceramic coating layer on its surface.

[0183] As previously described for mounting system 100, the nominal grid deflection h of grid support structure 150 lattice The arcuate degree may be the difference between the maximum height of the curved surface of the lattice support structure 150 at the center and the top surface of the edge of the lattice support structure 150. The difference between the maximum height of the curved surface of the lattice support structure 150 and the edge may be h lattice The length ratio L of the lattice support structure 150 may be r is the new x-dimension L of the lattice support structure 150 i and the length L0 of the original lattice support structure 150. The predicted maximum lattice deflection h Lr is the nominal grid deflection h lattice and the length ratio L of the lattice support structure 150 r is approximately proportional to the product of x and the square of x, which can be calculated according to the following formula: L r =L i / L0 therefore, h Lr ≒h lattice ×L r 2 .

[0184] Therefore, for a grid support structure 150 with xy dimensions of 635 mm × 190 mm (L × W), the maximum predicted grid deflection h Lr is approximately 3.8 mm. A longer lattice support structure 150, such as a lattice support structure 150 with xy dimensions of 1905 mm by 635 mm, has a length ratio of 3 (L r = 1905 / 635 = 3), which is 3.8 x 3 2 Maximum grid deflection h ≒ 34.2 mm Lr The nominal grating deflection may be from about 3 mm to about 35 mm. Thus, the amount of deflection of the grating support structure 150 may depend on the properties of the grating support structure 150. The longer the grating support structure 150 needs to be to accommodate a longer substrate, the higher / larger the deflection of the grating support structure 150 needs to be.

[0185] As previously described with respect to the mounting system 100, in an example, the grid support structure 150 provided herein can be self - supporting. The grid support structure 150 can be separated from and released from the jig. In an exemplary embodiment, the grid support structure 150 can be flatly placed on the jig. The exemplary grid support structure 150 can include a rim having a flat surface or plane around it. The curvature of the surface of the grid support structure 150 can be determined empirically based on data collected in initial tests performed using a ceramic plate, as will be considered with respect to the curved clamping die 170 described below. In a cross - section viewed from the side, the profile defined by the grid support structure may resemble the upper half of an ellipse where the semi - minor axis is much smaller than the semi - major axis. The ellipse can have an eccentricity close to but less than 1 (an eccentricity of 1 is a flat surface).

[0186] 3. Curved Clamping Die In an example, the mounting system 100 can include a curved clamping die 170.

[0187] In an example, the curved clamping die 170 can include one or more of the same or similar features as considered in the specification of International Application No. PCT / EP2020 / 082678, which is hereby incorporated by reference in its entirety. The curved clamping die 170 can be configured to include a predetermined substrate contact interface. In an example, the clamping die 170 can be configured to have a substrate contact interface that falls within the range of 0.1 to 20. In an example, the clamping die 170 may include one or more of the same or similar features as considered in the specification of International Application No. PCT / EP2020 / 082678 and may be configured to have a substrate contact interface that falls within the range of 0.1 to 20.

[0188] In an example, the curved clamp die 170 may be configured to include a substrate contact interface that is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 or more, and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or less. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.2 to 20, 0.2 to 15, 0.2 to 10, 0.2 to 5, or 0.2 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.3 to 20, 0.3 to 15, 0.3 to 10, 0.3 to 5, or 0.3 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.4 to 20, 0.4 to 15, 0.4 to 10, 0.4 to 5, or 0.4 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.5 to 20, 0.5 to 15, 0.5 to 10, 0.5 to 5, or 0.5 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.6 to 20, 0.6 to 15, 0.6 to 10, 0.6 to 5, or 0.6 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.7 to 20, 0.7 to 15, 0.7 to 10, 0.7 to 5, or 0.7 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.8 to 20, 0.8 to 15, 0.8 to 10, 0.8 to 5, or 0.8 to 1. In an example, the curved clamp die 170 may be configured to have a substrate contact interface in the range of 0.9 to 20, 0.9 to 15, 0.9 to 10, 0.9 to 5, or 0.9 to 1.

[0189] In an example, the curved clamp mold 170 may include an upper surface 174 as shown that defines a substrate interface area of the curved clamp mold 170. In an example, the substrate interface area of the curved clamp mold 170 may be different from, for example smaller than, the surface area of the upper surface 174. As described above, the substrate interface area should be understood as an area configured to be overlaid by a substrate or a preliminarily bent substrate when the curved clamp mold 170 is in use.

[0190] In an example, the substrate contact interface of the curved clamp mold 170 with respect to a given substrate interface area can be adjusted by modifying the curved surface of the curved clamp mold 170 configured to face the substrate or the preliminarily bent substrate during use. In an example, as described herein, the curved surface of the curved clamp mold 170 may be configured to have a planar profile, an irregular profile, one or more protrusions extending therefrom, and / or a knurled surface, a waveform, or other ridges and valleys as described herein, and any similar structure that may affect the size of the substrate contact area of the curved clamp mold 170.

[0191] In an example, the clamp mold 170 may include a first side that includes a peripheral rim. In an example, the peripheral rim may have a flat or planar surface on at least one side. In an example, the peripheral rim may have a flat or planar surface, a cavity or depression that forms one or more void areas, and one or more reinforcing members. The planar peripheral portion and the reinforcing members share a common plane. In an example, only the peripheral rim and the reinforcing members contact a jig or a clamping fixed platform. The curved clamp mold also includes a second side opposite the first side, as shown in FIGS. 5A - 5B, and the second side has a curved surface.

[0192] In use, the first side of the clamping die can be directed towards the welding fixture. The curved surface of the clamping die is directed towards the pre-bent substrate away from the fixture and can be positioned relative to the pre-bent substrate. The planar surfaces of the peripheral rim and the reinforcing member of the curved clamping die can be placed flat on the fixture surface. One or more clamps can be used to fix the pre-bent substrate to the fixture. Thereby, since the substrate or the pre-bent substrate is pushed towards the fixture, the force required to fix the substrate or the pre-bent substrate to the fixture is applied between the clamp and the fixture, and the curved clamping die serves as a support between the substrate and the fixture. In an embodiment, the pre-bent substrate is pressed axially downward.

[0193] The curved clamping die can be positioned such that the first surface of the curved clamping die faces the fixture. In an example, the planar surfaces of the peripheral rim and the reinforcing member on the first side of the curved clamping die can be placed flat on the fixture surface. The back side (first side) of the pre-bent substrate where the molten track may exist is positioned to face the side of the curved clamping die (the side facing away from the fixture (second side)). In this configuration, the back side of the pre-bent substrate faces downward towards the curved surface of the curved clamping die and the fixture. As described above, with the curved clamping die sandwiched between the pre-bent substrate and the fixture, one or more clamps can fix the pre-bent substrate to the fixture.

[0194] In an example, the curved clamping mold can be configured to have a greater thickness in the central portion than in the edge portion, and as a result, the curved surface has a maximum height near its center. In the embodiments provided herein, the height of the curved clamping mold measured at or near the central portion of the curved clamping mold can be in the range of about 3 mm to about 60 mm, or about 12 mm to about 50 mm, or about 15 mm to about 45 mm. The height of the curved clamping mold measured at or near the outer edge of the curved clamping mold can be in the range of about 0.5 mm to about 55 mm, or about 3 mm to about 45 mm, or about 10 mm to about 40 mm. In an example, the thickness profile of the curved clamping mold when viewed from the side has a maximum height at the central portion of the curved clamping mold, and the height can gradually decrease towards the outer edge of the curved surface. In an example, due to the difference in height across the cross-section of the curved clamping mold, a concave downward curve may occur on the upper surface of the curved clamping mold. In the cross-section viewed from the side, the shape of the curved clamping device may resemble the upper half of an ellipse with a minor axis much smaller than the major axis. The ellipse can have an eccentricity close to 1 but less than 1 (an eccentricity of 1 is a flat surface).

[0195] The curved clamping mold can be composed of any metal having sufficient strength and temperature resistance to be used under typical conditions of DED processing as described above. In an example, the curved clamping mold can be made of a rigid material resistant to torsion and deformation so as to help maintain its shape. In addition, the curved clamping mold can be made of a material resistant to thermal shock, corrosion, and non-magnetic.

[0196] As described above, in an example, in the implementation of the mounting system 100, no ceramic sheet, plate, or pylon and / or ceramic coating is used. In an example, the curved clamping mold 170 does not include a ceramic sheet or pylon, a ceramic coating, or both. In an example, the curved clamping mold 170 may include a ceramic coating as described. In an example, the curved clamping mold 170 may be used together with a ceramic sheet, plate, or pylon.

[0197] In an example, the thickness of the curved clamp mold 170 can be designed to mimic or provide the same or similar thermal insulation characteristics as those achieved by the ceramic insulation sheets conventionally used in the DED process. For example, one or more sheets or plates of alumina (Al2O3) insulation are used in conventional DED processes to thermally isolate the substrate from the clamping fixed platform such as a jig. The conventional use of the insulation sheet reduces the risk of potential thermal damage to the jig and at the same time contributes to a more uniform temperature distribution during the DED process. The thickness of the sheet or plate can vary, but the thickness of the conventionally used sheet is about 3 mm to 3.5 mm. In conventional DED processes, multiple ceramic insulation sheets can be used. For example, in some conventional processes, about 4 ceramic insulation sheets or plates are used to provide an insulation layer of about 12 mm. More or fewer ceramic insulation sheets can be used in conventional methods. These alumina insulation plates can be cut to size. However, doing so releases alumina particles, which can cause inflammation in the respiratory tract and eyes. Alumina insulation sheets also tend to be hygroscopic and can initially release water vapor during the heating temperature of the DED process, so the deposition environment can vary during processing, which is not desirable. Also, the ceramic insulation sheets conventionally used between the substrate and the jig are brittle and easily breakable, so they must be discarded after use and thus become consumables that increase the cost of DED manufacturing.

[0198] In an example, the curved clamping die 170 can be used in combination with a conventional ceramic insulating plate. The curved clamping die can replace the conventional ceramic insulating plate and can provide similar thermal insulation while maintaining the same height, so that the changes to the setting of the melting tool providing the heat source or the CAD-CAM path plan defining the piece manufactured by DED are minimal. As described above, other than the operation constraints that depend on the machine, there is no physical limitation on the thickness of the curved clamping die. For example, the height stroke of the DED system can define the thickness of the curved clamping die used. The thickness of the curved clamping die can be selected to maximize the reduction of heat flow at the die / fixture interface while ensuring sufficient clearance for the manufacture of the workpiece based on the height stroke of the system.

[0199] In an example, the curved clamping die 170 can include a ceramic coating. For example, as shown in FIG. 5B, a ceramic coating can be applied to the surface of the curved clamping die facing the DED substrate (the second curved surface including knurling or corrugation). The ceramic coating can be applied directly to the curved surface, or the ceramic coating can be applied to a bond coat that is directly applied to the second curved surface. The ceramic coating can be applied directly to the first flat surface on the opposite side of the die, or the ceramic coating can be applied to a bond coat that is directly applied to the first flat surface. The ceramic coating can provide thermal insulation to minimize or prevent thermal contact between the curved clamping die and the pre-bent substrate.

[0200] The process and characteristics of the ceramic coating applicable to the mounting system 100 have been described above, and are similarly applicable to the curved clamp mold 170. Also, as previously discussed, in an example, the mounting system 100 may include a bond coat. Similarly, in an example, the curved clamp mold 170 may include a bond coat as previously described. An example of an applied bond coat is schematically shown in FIG. 5C. The knurling 178 is coated with a bond coat 186, and the bond coat is then coated with a ceramic coating 184.

[0201] In an example, the mounting system 100 may include a corrugated surface and / or a knurled surface. Similarly, in an example, the curved surface of the curved clamp mold 170 can be physically modified to further minimize or prevent heat conduction between the curved clamp mold 170 and a pre-bent substrate.

[0202] Before applying the ceramic coating layer, a knurled surface can be cut into the curved surface of the curved clamp mold. Before applying the ceramic coating layer, a corrugated surface including a combination of ridges and valleys can be cut into the curved surface of the curved clamp mold. A corrugated surface including a combination of ridges and valleys, where the surface of one or more ridges has a knurled surface, can be cut into the curved surface of the curved clamp mold before applying the ceramic coating layer. Exemplary embodiments are shown in FIGS. 5A, 5B, 5D, and 5E. The embodiment shown in FIG. 5A shows a curved clamp mold 100 including an upper surface 174 having a knurled combination of knurling 178 at intervals 180, and a bottom surface having a flat or planar rim 182. The curved clamp mold can include edges 176 on each side, as shown in FIG. 5B. The edges 176 on each side of the mold can help support and / or restrict the downward movement of the short edges of the plate (substrate) during clamping.

[0203] In an example, the curved surface of the curved clamp mold 170 can include knurling, as shown in FIGS. 5D and 5E. The knurled surface on the curved surface of the curved clamp mold 170 can be fabricated as described previously with respect to the mount system 100.

[0204] In embodiments provided herein, the curved surface of the curved clamp mold 170 can include or can be made into a waveform. The curved surface of the mold can be made into a waveform such that it includes alternating ridges and grooves. The waveform can extend from one long side of the curved clamp mold 170 to the other long side. The waveform can extend from one short side of the curved clamp mold to the other short side. As a result of the waveform, a plurality of columns perpendicular to the arc of the curved clamp mold are formed. The periphery of the mold on the curved surface can be contoured by a metallic material and not coated with a ceramic coating or a bond coat.

[0205] The ridges can be in rows and can have the same characteristics and advantages as described previously. Exemplary ridges implemented on the curved clamp mold 170 are shown in FIGS. 5A, 5B, 5C, and 5E.

[0206] Similarly, as described previously with respect to the mount system 100, in an example, the knurling pattern or waveform on the curved surface of the curved clamp mold 170 can have a ceramic coating layer on its surface. An exemplary embodiment showing the curved clamp mold 170 having a ceramic coating 184 is shown in FIG. 5B.

[0207] As previously described with respect to the mount system 100, in an example, the nominal mold deflection h mold (camber) of the curved clamp mold, as shown in FIG. 5B, is the difference between the maximum height at the center of the curved surface of the curved clamp mold and the upper surface of the edge of the curved clamp mold. In FIG. 5B, the difference between the maximum height 198 of the curved surface of the curved clamp mold and the edge 176 is h mold is. The length ratio L r of the mold is the new x-dimension L iis the ratio to the length L0 of the original type. The predicted maximum type deflection h Lr is the nominal type deflection h mold and the square of the type length ratio L r are approximately proportional to the product of, and this is calculated according to the following formula: L r =L i / L0 Therefore, h Lr ≈h mold ×L r 2 .

[0208] Therefore, for a curved clamp mold with xy dimensions of 635 mm × 190 mm (L × W), the predicted maximum type deflection h Lr is approximately 3.8 mm. Longer molds, such as a curved clamp mold with xy dimensions of 1905 mm × 635 mm, have a type length ratio of 3 (L r = 1905 / 635 = 3) and a maximum type deflection h 2 ≈ 34.2 mm Lr will have. The nominal type deflection can be from approximately 3 mm to approximately 35 mm. Thus, the amount of mold deflection can depend on the characteristics of the mold. The longer the curved clamp mold needs to be to accommodate a longer substrate, the higher / greater the deflection of the curved clamp mold needs to be.

[0209] In an example, the curved clamp mold 170 can be designed to include a cavity or depression on the lower side of the mold while maintaining the rigidity and deformation resistance of the mold. An exemplary design is shown in FIG. 5F. A non-magnetic metal segment on the bottom surface of the curved clamp mold can be machined to create two or more cavities or depressions. The cavities or depressions can be separated from each other by an unmachined metal area that can function as a reinforcing member. An unmachined metal area can also be present at the periphery of the bottom surface of the mold to form a rim. This design reduces the amount of material required to manufacture the curved clamp mold 170 while still maintaining the physical stability of the mold. By reducing the need for a complete block of material used to form the mold, the weight of the mold can be reduced while maintaining the rigidity of the mold structure. Instead of machining the metal to achieve the desired cavities and reinforcing members, the curved clamp mold 170 can be fabricated by casting using a mold to include these attributes, minimizing the amount of material that needs to be removed to achieve the desired final design. Additionally, a reinforcing member can be added, such as by attaching a separately prepared reinforcing member to the bottom surface of the curved clamp mold 170. The reinforcing member can be attached by any suitable method. Exemplary methods include welding, screws, bolts, adhesives, or combinations thereof.

[0210] The cavity can have any shape. In an example, the cavity can be four triangular cavities separated by a mold material for forming an X-shaped reinforcing member that separates the cavities from each other. An exemplary embodiment is shown in FIG. 5F. In the configuration shown, the substrate is machined to form triangular cavities 188, 190, 192, 194 while leaving material for forming an X-shaped reinforcing member 196 and a flat peripheral rim 182. The outer surface of the flat peripheral rim 182 and the outer surface of the X-shaped reinforcing member 196 are in the same plane and can be placed flat on the surface of the jig when fixed to the jig. The cavity can be four square or rectangular cavities and is separated by a mold material to form an H-shaped reinforcing member that separates the cavities from each other. The cavity can be any shape selected from the group consisting of square, rectangular, oval, elliptical, trapezoidal, parallelogram, pentagonal, hexagonal, heptagonal, star-shaped, cross-shaped, multi-point star-shaped, intersecting geometric shapes, polygons, geometric shapes, irregular shapes, regular shapes, symmetric shapes, asymmetric shapes, and combinations thereof.

[0211] In addition to cost reduction achieved by reducing the amount of non-magnetic metal required for production, the cavity + reinforcing member + peripheral rim design offers several functional advantages. One advantage is that only the unmachined portion of the bottom surface of the mold contacts the high-strength steel jig. This reduces the conductive heat transfer from the curved clamping mold to the jig while maintaining the rigidity of the curved clamping mold. This reduction in heat transfer also contributes to heat retention in the pre-bent substrate, minimizing losses to the jig.

[0212] Furthermore, the cavity on the bottom surface of the curved clamping mold 170 can hold an atmosphere or argon gas. Argon can be effectively used as a thermal insulator under most of the mold due to the presence of the cavity and the peripheral rim. Argon is a very effective thermal insulator. The heat flow from the curved clamping mold 170 to the steel fixture below it occurs solely at the solid / solid contact interface by conductive heat transfer as a result of the thermal gradient. Since the solid / gas / solid interface has a much lower thermal conductivity, the cavity on the lower surface of the curved clamping mold 170 can effectively function as a thermal barrier (e.g., an air or inert gas gap) between the curved clamping mold 170 and the fixture. The air or inert gas gap can be utilized at the interface between the base plate and the clamping mold 170 and / or at the interface between the clamping mold 170 and the fixture, which helps to reduce the heat transfer from the base plate to the fixture. Thus, the curved clamping mold 170 helps to maintain more heat in the pre-bent substrate, thereby further reducing the non-uniformity of the temperature distribution and reducing the thermal stress of the pre-bent substrate.

[0213] In an example, the curved clamping mold 170 can exhibit high durability. After repeated use, the curved clamping mold 170 may experience thermal stresses that can cumulatively build up and result in a certain amount of small arcuate distortion of the mold (e.g., a lift of 0.05 mm to about 0.5 mm at the edge after repeated use). The degree of arcuate distortion observed in the curved clamping mold 170 after repeated use is not expected to significantly change the distortion reduction effect occurring in the DED preform. Different object designs may require the use of curved clamping molds 170 of different sizes to accommodate different sized substrates. Similar curved clamping molds 170 can be used in the manufacture of objects having similar shapes and / or substrate sizes. For example, objects having similar shapes and / or substrate sizes can be grouped into a family, and the same curved clamping mold design can be used within the same object family.

[0214] As described above with respect to the mounting system 100, in an example, the curved clamping die 170 provided herein can be self - supporting. The curved clamping die 170 can be separated and removed from the jig. In an exemplary embodiment, the curved clamping die 170 can be placed flat on the jig. The exemplary clamping die 170 can include a rim having a flat or planar surface at the periphery. The curvature of the die can be determined empirically based on data collected in initial tests performed using ceramic plates. The ceramic plates were cut into different sizes and used to generate different current curvatures, and tested for the ability to minimize the distortion of the preform prepared on the curved die. Thereafter, modeling was used to confirm that the experimentally used curvature results in a final result close to the target, i.e., a preform without distortion. In a cross - section viewed from the side, the shape of the curved clamping device may resemble the upper half of an ellipse where the semi - minor axis is much smaller than the semi - major axis. The ellipse can have an eccentricity close to 1 but less than 1 (an eccentricity of 1 is a flat surface).

[0215] 4. Modified jig design In an example, the mounting system 100 can be integrated into a welding jig. In an example, any of the exemplary structures described above, the pins 112, the pin support system 110, the grid support structure 150, and / or the curved clamping die 170 can be made an integral part of the welding jig. In an example, the surface of the welding jig 400 can be configured to mimic a curved surface or a substrate contact area as described for any of the pin support system, pins, grid support structure, and / or curved clamping die. By implementing any of these considered features on the surface of the welding jig 400, the same or similar advantages can be achieved.

[0216] C. Method of directed energy deposition Provided herein is a method of directed energy deposition for reducing or minimizing distortion in objects manufactured using directed energy deposition, particularly titanium and titanium alloy objects. The method includes thermally pre-bending the substrate on which the object is manufactured, attaching the pre-bent substrate to a mounting system provided herein, pre-heating the substrate prior to DED deposition, and manufacturing the object by depositing metal layers layer by layer. Thermally pre-bending the substrate includes inducing a steep thickness-wise thermal gradient in the substrate.

[0217] In the thermally induced pre-bending step, a heat source can be used to apply thermal energy at a high energy density to the surface of the first side or back side of the substrate. The thermal energy can be applied to a defined portion of the back side of the substrate to form a large thermal gradient in the substrate. The large thermal gradient can introduce a high residual stress field in the substrate. After applying the thermal energy, the temperature of the surface to which the thermal energy was applied can be decreased. In an embodiment, a gas jet device can be used to apply a cooling gas. The application of the cooling gas can increase the cooling rate and thereby further increase the stress imparted to the substrate. For example, the heat source can include an electric arc of a plasma torch such as a PTA torch, and the gas jet device can be attached to a support relative to the plasma torch as shown in FIG. 6. In FIG. 6, the gas jet device 200 is attached to the support 230, and the nozzle 210 of the gas jet device 200 can apply a cooling gas to the area heated by the PTA torch 250.

[0218] In contrast, in the preheating step, in order to minimize the temperature gradients along the x, y, and z directions, thermal energy is applied uniformly to the surface of the substrate. The thermal energy is applied as uniformly as possible to the front side of the substrate, to the extent permitted by the heating apparatus. Any heating apparatus or heating method that provides uniform heating can be used for preheating. For example, direct heating using a heater positioned to apply heat to the entire surface of the substrate can be used. The heating apparatus can be, or can include, an infrared heater, an induction heater, a resistance heater, or a combination thereof. Exemplary heaters include conductor-in-conduit heat sources, heater strips, resistance heating strips, infrared heaters, positive temperature coefficient ceramic heaters, thick film ceramic heaters, resistance wire or ribbon heating devices, infrared heaters, and induction heaters. Preheating can also be achieved using one or more melting tools to apply thermal energy to the surface of the substrate. The melting tools can be used alone or in combination with an infrared heater, an induction heater, a resistance heater, or a combination thereof. The melting tools can include an electric arc plasma, a laser beam, or an electron beam as a heat source, and multiple melting tools including the same or different heat sources can be used. The heating area can be maximized by using a lower energy density and applying more thermal energy over a larger area. Multiple heat sources can be used in tandem, in series, or in parallel to generate multiple "lines" of thermal energy applied to the front surface of the substrate, and the substrate can be heated more uniformly. Thereby, the temperature of the substrate can be increased more uniformly using low energy density heating, and in particular, the thermal gradient in the thickness direction can be hardly generated or minimized. During the dry run of preheating (application of heat without adding molten metal), by applying thermal energy using one or more melting tools, residual contaminants such as contaminants remaining from ultrasonic / wiping cleaning procedures can be effectively removed from the surface of the substrate. Preheating is performed until the target temperature of the substrate is reached.

[0219] In some applications, the target temperature achieved by the preheating process is the DED process temperature, such as the DED deposition temperature, or about ±25 °C of the DED process temperature. In some applications, the target temperature is within ±25 °C of the plastic deformation temperature of the substrate. In some applications, preheating is performed until the temperature of the substrate reaches about 400 - 900 °C. In some applications, preheating is performed until the substrate reaches a temperature of about 500 - 850 °C. Other authors have reported that warm forming can also be performed between 200 - 300 °C to reduce flow stress and minimize the bounce-back of titanium. In some applications, preheating is performed until the substrate reaches a temperature of about 595 - 815 °C.

[0220] The mounting system 100 can function as a support for the pre-bent substrate when the pre-bent substrate is clamped to the fixture. Among other advantages, the mounting system 100 provides a more consistent and reproducible end residual stress distribution and helps to minimize workpiece distortion during and after manufacturing.

[0221] DED can be performed after the substrate has been preheated (and remains heated) in order to reduce the generation of thermal gradients, particularly in the thickness direction (z-direction), during the DED process. Although it is optimal not to introduce stress into the manufactured object, the DED process is essentially a welding process, and usually, residual stresses and deformations induced by welding during manufacturing are inevitably accumulated. By reducing such residual stresses and deformations, dimensional accuracy is improved, and an object with excellent mechanical properties can be obtained. The steps of this method are described in more detail below.

[0222] 1. Pre-bending of the substrate In the methods provided herein, the substrate can be pre-bent prior to deposition. This pre-bending of the substrate can be a separate step of the DED process. In the methods provided herein, thermal energy can be applied to a first side of the substrate to plastically deform the substrate, and thus the substrate can be permanently and uniformly pre-bent. In embodiments, when thermal energy is applied across the surface of the first side of the substrate, one or more self-generated melt tracks or weld lines can be formed. This is significantly different from physically restraining the substrate using clamps and mechanically pre-bending it by mechanical stress. Mechanical pre-bending can be used to bend the substrate, but mechanical stress typically does not involve local melting of a planned segment of the substrate surface and is insufficient to introduce the desired uniform plastic deformation into the substrate. Mechanical forces introduce a different stress redistribution pattern than that introduced by applying local heating after the substrate is released from the clamps. For example, when a substrate pre-bent with mechanical forces is released, the substrate springs back to a much higher state than pre-bending by heat.

[0223] In embodiments, the substrate can have a first side and an opposite second side. The first side can be the side facing the fixture during DED manufacturing, and the second side can be the side on which the workpiece is formed by DED. In the case of pre-bending, the substrate can be clamped to the fixture with the first side facing up and the back side facing down towards the fixture.

[0224] Pre-bending of the substrate can be performed while the substrate is in a flat state. The pre-bending of the substrate can be performed with the substrate firmly connected to the jig using a plurality of clamps. The pre-bending of the substrate can be performed while the substrate is thermally isolated from the jig. The substrate can be thermally isolated from the jig by including one or more alumina insulating sheets having the same dimensions as the substrate. In an embodiment, four alumina insulating sheets can be used. Other materials that can thermally isolate the substrate from the jig can be used. Whether or not there is a ceramic coating for providing thermal insulation is not a concern, but an apparatus having the same thermophysical properties as the mounting system 100, such as a corrugated surface having a series of ridges and valleys defining a flat profile instead of a curved profile, a pin support system, a grid system, a mold, etc., can be used. By using such an apparatus, the need to use an alumina insulating sheet or a sheet of other insulating material may be eliminated.

[0225] The substrate can be clamped to the jig using clamps at the entire peripheral edge of the substrate along all four sides of the substrate. In some applications, the substrate can be attached to the jig using clamps only along two of the longest opposing sides of the substrate. This configuration allows a heat source such as an electric arc plasma, a laser, an electron beam device, or any combination thereof to move to the edge of the substrate in the longitudinal direction. This clamp arrangement may enable energy to be supplied from edge to edge and generate a stress field across the entire edge of the substrate, which helps to counteract subsequent residual stresses introduced during DED manufacturing in this particular area.

[0226] By applying strong thermal energy up to the entire edge or within about 5 mm from the edge, it has been found that the twist of the substrate can be minimized or prevented. As the distance from the edge to the end position of the application of high thermal energy increases, the twist also increases. The thermal stress generated when the DED heat source is applied from the edge up to 10 mm is significantly different from the thermal stress achieved when the heat source is applied up to above the edge or when the heat source is applied only up to 20 mm from the edge. When considering the distance from the edge that can be tolerated without concern for stress formation, it has been found that the thickness of the substrate hardly changes. When the substrate is thicker, it may be necessary to supply high arc energy (or heat input) during pre-bending, thereby achieving a wider and deeper fusion profile. This can be achieved, for example, by reducing the traverse speed, increasing the amount of applied thermal energy, or combining both. In the example, the structure of the tall DED preform also has less distortion compared to the low-profile structure, which means that the radius of curvature of the curved profile can increase with respect to the low-profile structure.

[0227] The clamp can be used to attach the substrate to the fixture, and a certain clamping force can be applied to all clamps. This can be achieved by tightening the bolts connecting the clamp to the fixture with torque control. During the pre-bending stage, a force of 10 Newton meters (N·m) to 20 N·m, for example, 15 N·m, can be used to tighten the bolts connecting the clamp and the fixture. Higher torque can be used for thicker substrates.

[0228] The DED heat source generates thermal energy to sufficiently melt the planned segments of the substrate surface in a predetermined order or position, or both, to form self-generated melting lines on the substrate surface. To rapidly cool the melt track, a gas jet device that directs cooling gas towards the melt track can be used. The heating or heating / cooling thermal cycle can induce the formation and development of controlled residual stresses in the substrate. As a result, uniform thermally induced pre-bending of the substrate can be achieved, or controlled to a predetermined level if necessary.

[0229] The DED heat source can be configured to supply sufficient thermal energy to induce a melt track on the DED substrate at a relatively fast speed. When used, the gas jet device can supply a large amount of cooling gas, such as 100 L / min to 200 L / min, to impose a rapid heating / cooling cycle on the substrate surface. For example, using a plasma transfer arc system, and a substrate thickness of 9.5 mm to 10 mm, a current of 190 amperes, a voltage of 25.5 V, and a traverse speed of 10 mm / s, a melt track with a width of approximately 3 mm and a maximum depth of 1 mm can be formed. This can correspond to an arc energy supply of approximately 485 J / mm. The energy and traverse speed can be adjusted for thicker substrates. An exemplary embodiment is shown in FIG. 7A. In the embodiment shown, a substrate 300 having a first side 310 is shown to have melt tracks 350 and 360 on the first side 310 with an interval 355 between the melt tracks 350 and 355, and a DED back wall of a preform 330 on a second side 320 of the substrate 300.

[0230] In addition to the cooling gas from the gas jet device that promotes a high cooling rate, the rapidly applied high temperature can result in the formation of a very steep thermal gradient towards the melt track and the substrate (along the x, y, and z directions). A high stress state close to the material yield strength of the substrate material can be achieved.

[0231] Any gas jet device that can be configured to supply a cooling gas to the molten surface of the substrate to rapidly cool the molten surface can be used. In the case of a Ti or Ti alloy material, an inert gas can be used as the cooling gas. The inert gas can be argon, helium, krypton, xenon, or a combination thereof. The gas jet device can include pipes, tubes, or other conduits, or combinations thereof, that can carry the cooling gas from the gas supply section to the application area. The gas jet device can include a first end attached to the gas supply section and a second end that can be positioned to direct the cooling gas exiting from the second end toward a desired location on the substrate such that the cooling gas impinges on the surface of the substrate, particularly the area of the molten metal of the molten track. To enhance or facilitate the cooling of the molten track, a plurality of gas jet devices can be utilized. The second end of the gas jet device can include one or more nozzles that can be adjustably positioned to direct the cooling gas toward the target location. The effect of the cooling gas impinging on the substrate surface can be maximized in the vicinity where the cooling gas directly impinges, but the peripheral area of the substrate can also be advantageously affected to lower the temperature in the vicinity of the cooling gas. A pulsed gas flow can be used for the supply of the cooling gas. To enhance the cooling efficiency, a fully turbulent gas flow can be used. Cooling gas jet devices are known in the art (see, for example, U.S. Patent No. 4,090,697 (Perrine, 1978); No. 6,390,115 (Rohwer et al., 2002); and No. 7,381,364 (Yamashita, 2008)). An exemplary gas jet device is described in U.S. Patent Application No. 16 / 019,460 (filed on June 26, 2018).

[0232] The pipes, tubes, or conduits of the gas jet device can be of any material having channels extending therethrough that are compatible with the conditions expected to exist during DED deposition. The gas supply source can be any source of cooling gas, such as a compressor or a container of high-pressure gas, that is in fluid communication with the gas jet device. Methods of supplying pressurized gas to the gas conduit are known in the art.

[0233] The cooling gas can be supplied to provide a target flow rate of the gas impinging on the substrate surface. The flow rate of the gas can be greater than 50 L / min, or greater than 100 L / min, or greater than 150 L / min, or greater than 200 L / min. The flow rate of the gas can be between 50 L / min and 500 L / min. The flow rate of the gas can be between 50 L / min and 250 L / min. The flow rate of the gas can be between 50 L / min and 100 L / min. The flow rate can be selected for high-speed cooling and thus for the formation of high heat and stress gradient conditions in the substrate.

[0234] The cooling gas can include inert gases such as argon, helium, neon, xenon, krypton, and combinations thereof. The cooling gas can be applied in a continuous stream, intermittently, or in a pulsed flow. The temperature of the cooling gas is arbitrary. The temperature of the cooling gas can be the ambient temperature of the additive manufacturing process. The cooling gas temperature can be applied at a gas temperature of about 100 °C or less. The cooling gas temperature can be about room temperature or less, for example about 25 °C or less. The cooling gas temperature can be in the range of about -10 °C to about 80 °C.

[0235] For a preform or workpiece formed on the second surface of the substrate, the number of DED walls having a centerline parallel to the short side of the substrate and the number of DED walls having a centerline parallel to the long side of the substrate can be determined. When most of the DED walls of the preform or workpiece have a centerline parallel to the short side of the substrate, a molten track parallel to the short side of the substrate can be formed. Generally, for a substrate with a large length-to-width aspect ratio, it is necessary to form a molten track along the longest axis, i.e., the axis along which the influence of strain is expected to be the greatest. When most of the DED walls of the preform or workpiece have a centerline parallel to the long side of the substrate, a molten track can be preferentially formed parallel to the long side of the substrate to counteract the greatest influence of strain along the long axis of the substrate.

[0236] Thermally induced pre-bending on the first or back side of the substrate can be applied such that the resulting melt tracks and the typical distribution of longitudinal and transverse residual stresses caused by welding are positioned approximately 10 mm to approximately 20 mm away from the centerline of most of the DED wall of the preform or workpiece deposited on the second or front side of the substrate. The pre-bending forming technique applied to the first side of the substrate can be implemented such that the resulting melt tracks are positioned approximately 10 mm, or 11 mm, or 12 mm, or 13 mm, or 14 mm, or 15 mm, or 16 mm, or 17 mm, or 18 mm, or 19 mm, or 20 mm away from the centerline of the DED wall of the workpiece deposited parallel to the long side of the substrate on the second or front side of the substrate. The melt tracks can be positioned such that they can be under the minimum area of the DED wall of the workpiece. An exemplary embodiment is shown in FIG. 7A.

[0237] Prior knowledge regarding the shape of the DED workpiece deposited on the second side of the substrate can be used to determine the pre-bending heating procedure applied to the first side of the substrate. The heating procedure can be designed to result in a minimum number of melt tracks under the area where the DED workpiece is built. The final combined residual stress distribution resulting from the combination of both DED and melt tracks has a lower tensile peak at the DED centerline and lower balanced compressive stresses further away from the DED centerline compared to the original residual stress profile of DED without pre-bending melt tracks (i.e., there is a high tensile peak at the DED centerline and balanced compressive stresses further away).

[0238] Exemplary embodiments showing the application of thermal energy to form a molten track on a substrate are shown in FIGS. 7A - 7D. The diagram of FIG. 7B shows the process of forming the molten track 350. As shown, the substrate 300 can be placed on the welding jig 400 and clamped with one or more clamps 500. In this step, the mounting system 100 is not used and the substrate 300 can be placed flat against the welding jig 400. Thereafter, a DED such as the plasma torch 250 can also be used to form a molten track on the surface of the clamped substrate 300. In the example, the molten track extends from the first end of the substrate 300 to the opposite second end of the substrate 300. FIG. 7D schematically shows an exemplary heating path that can be used to move the DED energy source to form a molten track on the back side or the upper surface of the first side of the substrate to pre - bend the substrate towards the heat source. The black arrows indicate the direction / path of the DED energy source, and X ES The circles containing are shown a sequence X where X is 1 - 6 across the surface of the first side 310 of the substrate 300, S indicates the starting point of the energy application path that results in the heating path, and E indicates the end point of the path. In the pattern shown, the heating can start at the upper edge crossing the x - direction (1 ES ), then the heat source can be moved in the y - direction to a point less than half way across the substrate and heat can be applied in the y - direction from short side to short side (2 ES ). This procedure can be repeated for 3 ES , 4 ES , 5 ES , and 6 ES . The first heating path 370 corresponds to 1 ES . The second heating path 371 corresponds to 2 ES . The third heating path 372 corresponds to 3 ES . The fourth heating path 373 corresponds to 4 ES . The fifth heating path 374 corresponds to 5 ES . The sixth heating path 375 corresponds to 6 ES .

[0239] A predetermined DED heating / cooling thermal cycle can induce the controlled formation and development of residual stress in the substrate. The application of cooling gas using a gas jet device (not shown) can be used to facilitate cooling. As a result, uniform thermally induced pre-bending of the substrate can be achieved / controlled to a predetermined level.

[0240] Figure 7D schematically shows the relative position of the thermally induced pre-bending melt tracks formed by heating paths 370 - 375(1 ES - 6 ES shown as) on the back or first side of the substrate, with respect to the overlay (gray dashed line) DED workpiece preform 600 manufactured on the opposite front or second side of the substrate. The melt tracks can result from the application of thermal energy in the heating paths.

[0241] The heat source of the melting tool can heat the back side of the substrate to form melt tracks at predetermined positions on the substrate and impart thermal stress to the substrate. This thermal stress can cause the substrate to bend. Since the substrate can be firmly clamped to the fixture, the bending of the substrate is not noticeable while it is attached to the fixture. When the clamp is removed, the substrate may bend upward in an arch shape away from the fixture, i.e., in the direction of the heat source. The uniformly deformed pre-bent substrate can be defined by a clear radius of the arch. After removing the clamp to the fixture, the resulting uniform elastoplastic pre-bending effect on the substrate caused by the application of thermal energy is shown in FIGS. 7B and 8A. The resulting substrate 300 curves upward away from the fixture 400, showing the nominal substrate deflection. In FIG. 8B, the substrate is inverted. As seen in FIG. 8B, the pre-bent substrate has a uniform elastoplastic bend (camber) resulting from the application of strong thermal energy and cooling gas to induce a large temperature gradient and stress gradient on the back side of the substrate. FIG. 8B shows the nominal substrate deflection 410.

[0242] The thermal-induced substrate pre-bending procedure can result in a longitudinal residual stress distribution. Comparing the residual stress maps of a plurality of pre-bent substrates thermally pre-bent as described herein, a large tensile stress develops at the weld centerline (up to +σ of 600 MPa L ), and a characteristic residual stress distribution is demonstrated that balances with a further compressive stress (up to -σ of -300 MPa L ).

[0243] The nominal substrate deflection h of the substrate along the z-direction of a substrate having dimensions 635 mm × 190 mm × 9.5 mm (L × W × T) sub (camber) (h sub = z max - z min ) can be 15 mm after applying thermal-induced substrate pre-bending. This is a measured value and is also verified by modeling. The length ratio L of the substrate r is the ratio between the new x-dimension L of the substrate i and the length L0 (635 mm) of the substrate. The predicted maximum substrate deflection h Lr is approximately proportional to the product of the nominal substrate deflection h sub and the square of the length ratio L of the substrate r , which is calculated according to the following formula: L r = L i / L0 Therefore, h Lr ≒ h sub × L r 2 .

[0244] As an example, a longer substrate size with a substrate length ratio of 3 (i.e., L r = 1905 / 635 = 3) is expected to bend into an arc of 15 × 3 2 = 135 mm after applying thermal-induced substrate pre-bending. Thus, the amount of deflection of the substrate can depend on the characteristics of the substrate. The longer the substrate, the higher / larger the deflection needs to be.

[0245] The heat source for supplying thermal energy to form a molten track on the back side of the substrate can be any energy source capable of supplying sufficient thermal energy to melt the substrate in the heat application area to form the molten track. Exemplary heat sources that can be used include electric arc plasma, laser beam, electron beam, and any combination thereof. In some configurations, two or more melting tools providing separate heat sources can be used. For example, one melting tool providing a heat source can be used to preheat the substrate, and a second melting tool providing a heat source can be used to melt the preheated substrate to form the molten track. If multiple melting tools providing separate heat sources are used, they may be the same or different from each other. Examples of combinations of multiple melting tools providing DED heat sources include two PTA torches generating electric arc plasma, two laser devices generating laser beams, two electron beam devices generating electron beams, a PTA torch generating electric arc plasma and a laser heat source generating a laser beam, a PTA torch generating electric arc plasma and an electron beam heat source generating an electron beam, and a laser device generating an electron beam and an electron beam device generating an electron beam.

[0246] To form a molten track, sufficient heat can be applied to the substrate surface to heat the substrate such that at least a portion of the substrate is melted in the heat application area. The target temperature supplied by the heat source can be the melting temperature of the substrate material, or a temperature 5 °C to 50 °C higher than the melting temperature of the substrate, or a temperature 10 °C to 20 °C higher than the melting temperature of the substrate. Local heating of the substrate can serve to induce stress in the substrate to produce a highly stressed substrate in an elastoplastic state. When the substrate is unclamped from the fixture, the substrate bends into an arch to form a pre-bent substrate, stabilizing or balancing the residual stress imparted by the pre-bending step. Generally, the highest stress can be induced in the molten track, with a tensile stress peak occurring at the centerline of the molten track. The peak of the tensile residual stress can be close to the yield strength of the material. As the distance from the centerline increases, the residual stress becomes compressive. Whether sufficient stress has been induced can be confirmed by observing the amount of upward displacement (i.e., camber). The greater the displacement, the higher the residual stress introduced during pre-bending. In most substrates, the maximum tensile residual stress is close to the yield strength of the base material. The order and position of these molten tracks for DED can be varied to achieve the target residual stress redistribution.

[0247] The amount of heating required to induce the target stress and the number of melt tracks formed on the back side of the substrate can be determined experimentally. For example, without preliminarily bending the first substrate, an object can be manufactured on the first substrate using DED, and the resulting distortion of the substrate can be measured. Next, a second substrate having the same characteristics as the first substrate can be preliminarily bent by forming an amount of melt tracks on the back side of the second substrate necessary to fully or partially compensate for the amount of distortion measured with the first substrate. The amount of heating required to induce the target stress and the number of melt tracks formed on the back side of the substrate can also be determined based on modeling predictions, modeling, calculations, or combinations thereof. Modeling can be used, for example, to predict the distortion and development of residual stress in the substrate, and experiments can be used to confirm the predictions of the modeling. It has also been found that simulations agree very well with experimental data. In some embodiments, in addition to the predetermined arrangement of melt tracks from about 10 mm to about 20 mm from the centerline of the preform, the melt tracks can also be formed along the longest substrate length on parts having a high aspect ratio. Assuming a relatively symmetric preform shape in the form of a square is manufactured on a square substrate, a cross-shaped preliminary bending thermal energy application pattern can be used on the underside of the substrate to induce bending in both the longitudinal and transverse directions. As a result, the mount system can take a dome shape.

[0248] After formation, the preliminarily bent substrate can be handled in a consistent manner as can be done with conventional substrates. To maintain consistency, the temperature of the preliminarily bent substrate can be selected and the same temperature can be used for the formation of similar preforms. The temperature of the preliminarily bent substrate can be room temperature during use and when fixed to the fixture. The temperature of the preliminarily bent substrate can be 50 °C or higher when fixed to the fixture and used. In a typical additive manufacturing process, the number of substrates required to manufacture the target number of preforms can be determined, a sufficient number of preliminarily bent substrates can be manufactured one by one, and then each can be individually fixed to the fixture at a target temperature such as room temperature.

[0249] 2. Fixing the preliminarily bent substrate to the jig After the preliminary bending of the substrate is completed, the preliminarily bent substrate can be attached to a jig or a welding table. For example, a clamp attached to the jig can be used to attach the preliminarily bent substrate to the jig. The mounting system 100 can be used as a support lying under between the preliminarily bent substrate and the jig. The preliminarily bent substrate can have the same curvature as the mounting system 100. The preliminarily bent substrate can have a curvature different from that of the mounting system 100. The preliminarily bent substrate can be positioned such that the back side having a melting track can contact the curved surface of the mounting system 100. The clamp attached to the jig can apply a force to the preliminarily bent substrate to elastically deform the preliminarily bent substrate. The clamp can force the preliminarily bent substrate to conform to the curvature of the mounting system 100. The clamp can be made of high-strength steel, ultra-high-strength steel, or high-strength low-alloy steel.

[0250] As the clamp advances to fix the preliminarily bent substrate to the jig, the curvature of the preliminarily bent substrate gradually becomes similar to the curvature of the bending profile defined by the mounting system 100. As a result of the clamping, the curvature of the preliminarily bent substrate can become the same as the maximum deflection of the bending profile defined by the mounting system 100. Sufficient force can be applied by the clamp to conform the surface of the preliminarily bent substrate to the bending profile defined by the mounting system 100. Since the resistance of the substrate increases as it gets thicker, the clamp may be required to apply a greater force to overcome the elastic reaction of the pre-bending. The amount of force required for the clamp to attach the preliminarily bent substrate to the jig and to match the preliminarily bent substrate to the bending profile defined by the mounting system 100 can be from about 10 Nm to about 120 Nm. For example, in the case of a Ti-6Al-4V substrate having a thickness of about 9.5 mm to 10 mm, only 40 Nm of torque can be exerted by the clamp to attach the preliminarily bent substrate to the jig and to conform the preliminarily bent substrate to the bending profile defined by the mounting system 100.

[0251] The clamp can apply torque to apply an initial clamping force to the substrate and then can apply additional torque to apply a final torque to the substrate. The initial clamping can be achieved by sequentially tightening the clamp or by tightening the clamps positioned on opposite sides of each other. The curvature of the preliminarily bent substrate can gradually become similar to the curvature of the bending profile defined by the mounting system 100.

[0252] Due to the curvature of the curved profile defined by the mounting system 100, in an example, the torque applied to the substrate via the clamp can be made significantly smaller than the torque that would be required to flatly attach a pre-bent substrate to a jig without using the mounting system 100. The curvature of the curved profile defined by the mounting system 100 can be mimicked by plate boundary conditions. To achieve a satisfactory clamp, (a) a consistent clamping force can be used by torque-controlling the bolts to which the clamp is attached, (b) a consistent dimension can be selected from the clamp, (c) the clamp can be applied symmetrically, (d) an even pressure distribution and heat transfer distribution can be ensured by properly attaching the clamp to avoid gaps and non-uniform pressure application, or (e) any combination of (a) to (d) can be arbitrarily combined. For example, the clamp can be attached to the base plate via socket head cap screws flush with the upper surface of the clamp to ensure an even distribution between the clamp and the base plate. The bottom and side contact facets of the clamp can be configured and arranged to contact the base plate in the same plane to ensure an even pressure and an even heat transfer distribution. For example, refer to FIGS. 14A and 14B. The dashed circles 544, 545, 546, 547, 548, 549 in FIG. 14A indicate areas with non-uniform pressure and heat transfer distribution due to the method of adjusting the bolt 520 adjusted via the socket head cap screw 510 and the nut 525 to adjust the clamp 500 to attach the base plate 550 to the surface 530 of the jig. In the example shown, the base plate 550 is thermally insulated from the jig surface 530 by a layer of alumina insulating plates 540 to 543.

[0253] To avoid non-uniform pressure and heat transfer distributions, as shown in FIG. 14B, the dish screw 510 can be adjusted so that the tip 515 of the dish screw 510 is flush with the upper surface 507 of the clamp 500. By doing so, a uniform pressure and heat transfer distribution can be obtained. The boxes 575, 576, 577, 578 in FIG. 14A show the areas of uniform pressure and heat transfer distribution achieved for the method of adjusting the bolt 520, which is adjusted via the dish screw 510 and nut 525, to attach the clamp 500 to the base plate 550 on the surface 530 of the jig. In the illustrated embodiment, the bottom contact facet 505 and the side contact facet 507 of the clamp 500 are shown to be flush with the upper and side surfaces of the base plate, respectively, to ensure an even pressure and heat transfer distribution.

[0254] When the mount system 100 is used as a support lying horizontally below to attach a pre-bent substrate to a jig, the longitudinal residual stress may be slightly redistributed. For example, the +σ L tensile stress peak at the weld centerline can increase from about 600 Mpa to about 700 Mpa, and the -σ L compressive stress away from the centerline can decrease from about -300 Mpa to about -200 Mpa.

[0255] The clamping of a pre-bent substrate to the mount system can be done in an elastic mode. The curvature imposed by clamping the substrate to the mount system can be fully reversible at this point if the substrate is unclamped from the mount system 100. This is particularly true for metal substrates with high springback at room temperature. The elastic deformation imposed by the clamping force can be distinguished from the plastic deformation introduced into the substrate in the pre-bending step.

[0256] Clamps used to fix the substrate to a jig or welding table can usually be made from materials that exhibit high strength and low deformability. Steel can be used as a clamp material due to its high strength, thermal stability, and resistance to deformation. Steel can usually have a higher thermal conductivity than the substrate. In many substrates, the heat transfer of the steel within the clamp can be orders of magnitude higher than that of the substrate. Due to this difference in thermal conductivity between the clamp and the substrate, the clamp may function as a heat sink. As a heat sink, the clamp that directly contacts the substrate during the DED process can cause a rapid flow of thermal energy from the area of the substrate adjacent to or in proximity to the attachment point of the clamp, through the clamp, and then to the jig or welding table. As a result, a high thermal gradient can occur in the pre-bent substrate during the DED process. The high thermal gradient can impose stress and strain on the substrate during the deposition process.

[0257] To reduce or prevent the formation of a thermal gradient due to the clamp functioning as a heat sink, the clamp can be thermally insulated. Thermal insulation can reduce or prevent the transfer of heat from the substrate, through the clamp, to the jig. An insulating coating can be applied to the entire surface of the clamp. An insulating coating can be applied to the entire surface of the clamp that can come into contact with the substrate. The insulating coating can be any coating that does not effectively transfer thermal energy. The insulating coating can be made of a ceramic material, silicon carbide, silicon nitride, boron carbide, or any combination thereof. The ceramic material can be alumina, zirconia, titanium oxide, alkaline earth metal silicate, aluminum titanate, zirconium dioxide stabilized by the addition of yttrium oxide, yttrium aluminum oxide, ZrV2O7, Mg3(VO4)2, or any combination thereof, or can include them. Any high-temperature ceramic coating known in the art can be used (see, for example, U.S. Patent Nos. 4,321,310 (Ulion et al., 1982), 5,789,330 (Kondo et al., 1998), 5,304,519 (Jackson et al., 1994), 6,387,539 (Subramanian, 2002), and 6,998,064 (Gadow et al., 2006)). The clamp can be coated with zirconium dioxide stabilized by the addition of yttrium oxide, such as plasma-sprayed ZrO28Y2O3. The insulating coating can include multiple layers of different types of ceramics, carbides, nitrides, or combinations thereof, or multiple layers of one type of ceramic, carbide, nitride, or combination thereof.

[0258] Many of these materials are commercially available and can be applied using various techniques known in the art. For example, the insulating coating can be applied using any process including chemical or electrochemical vapor deposition such as atmospheric plasma spraying, magnetron sputtering, electrophoretic deposition, or physical vapor deposition such as electron beam physical vapor deposition, or any combination thereof.

[0259] The thickness of the insulating coating applied to the clamp can vary depending on the type of insulating material used and its ability to support the load without being damaged by the application of the compressive force. In some configurations, the thickness of the insulating coating can be 0.1 mm to 5 mm, or 0.25 mm to 4 mm, or 0.3 mm to 3 mm, 0.4 mm to 2 mm, or 0.5 mm to 1.5 mm. The insulating coating can be at least 0.1 mm, or at least 0.25 mm, or at least 0.5 mm, or at least 0.75 mm, or at least 1 mm, or at least 1.25 mm, or at least 1.5 mm, or at least 2.0 mm, or at least 2.5 mm, or at least 3.0 mm, or at least 3.5 mm, or at least 4.0 mm, or at least 4.5 mm. The insulating coating can have a thickness of 0.1 mm, or 0.25 mm, or 0.5 mm, or 0.75 mm, or 1 mm, or 1.25 mm, or 1.5 mm, or 2.0 mm, or 2.5 mm, or 3.0 mm, or 3.5 mm, or 4.0 mm, or 4.5 mm, or 5 mm. The insulating coating layer can reduce the heat transfer from the DED substrate to the fixture, thereby reducing the heat loss from the DED substrate. An example of the insulating coating is 0.5 mm to 1.5 mm of ZrO2 8Y2O3 plasma sprayed on the contact surface of the clamp to help reduce the conductive heat transfer from the DED substrate to the clamp. This can increase the thermal insulation and reduce the thermal conductivity.

[0260] To further reduce the heat conduction from the substrate to the fixture via the clamp, the surface of the clamp that is thermally in communication with the substrate can be modified to have a knurled pattern. Knurling of the surface can reduce the amount of the clamp surface that contacts the substrate. Knurling can reduce the possibility of heat conduction between the clamp and the substrate. Any knurled pattern known in the art can be used for the surface of the clamp that may contact the substrate. Exemplary knurled patterns include diagonal patterns such as diagonal patterns, straight line patterns, diamond patterns, or any combination thereof. The knurled pattern can also have an insulating coating layer on its surface.

[0261] To reduce the heat transfer from the substrate to the fixture via the clamp, the surface of the clamp that is thermally in communication with the substrate can be modified to have a corrugated surface including a series of ridges and valleys. The corrugated surface can reduce the amount of the clamp that contacts the substrate. The corrugated surface can reduce the possibility of heat conduction between the clamp and the substrate. Any corrugated pattern known in the art can be used. The corrugations can be present in any direction on the surface of the clamp. Exemplary configurations include diagonal corrugations such as diagonal corrugations, straight line corrugations parallel to the long side, straight line corrugations parallel to the short side, or any combination thereof. The corrugated surface can also have an insulating coating layer on its surface.

[0262] Due to the limitations of coating technology, a thicker layer of insulating coating that can withstand the compressive force required to fix a preliminarily bent substrate to the fixture may be more difficult to achieve. The specific compressive strength of the insulating coating can be determined by the composition of the insulating coating. For example, a 0.5 - 2.0 mm coating of a ceramic mainly composed of zirconium dioxide stabilized by the addition of yttrium oxide has been found to provide good thermal insulation with good compressive resistance without damaging the insulating coating when connecting the substrate to the fixture using a clamp.

[0263] Exemplary configurations of the clamp are shown in FIGS. 9A, 9B, and 9C. FIG. 9A shows the bottom surface of a clamp 500 having a screw hole 501 for receiving a socket screw and a hole 502 for accommodating a bolt. The upper surface 507 can include a ceramic coating surface 509 at an edge that contacts the base plate. The upper surface 507 can be corrugated. FIG. 9B shows a side view of the clamp 500 showing the ceramic coating surfaces 509 of the bottom contact facet 505 and the side contact facet 506 that contact the base plate. FIG. 9C shows a perspective top view showing a three-dimensional view of the clamp 500, showing the screw hole 501 and the ceramic-coated bottom contact facet 505 and side contact facet 506 of the clamp 500. Clamps of the same design can be used (e.g., all having the same length, or the same width, or the same length and width). Clamps having different lengths and / or widths can also be used.

[0264] In an example, thermally insulated clamps can be placed around the entire perimeter of a pre-bent substrate. As an exception to using only insulated clamps, a PTA torch may be used as a DED melting tool to supply an electric arc plasma as a heat source. In such a configuration, one or more non-insulated clamps can be used to provide a path for current. For example, in an exemplary configuration, two or three non-insulated clamps can be used to ensure a stable current path from the power source. In such a configuration, one or two non-insulated clamps can be positioned on the short side of the base plate, and one non-insulated clamp can be positioned in the middle section of the longest dimension of the base plate. Other configurations can also be used.

[0265] To reduce the stress and strain of the substrate during metal deposition and object manufacturing, the clamp can be positioned on the substrate such that the centerline of the clamp intersects the start / end position of the DED string / wall as much as possible. An exemplary configuration is shown in FIG. 10. In the configuration shown, the clamp 500 is positioned around the preform 600 such that substantially all of the periphery of the substrate 300 is clamped to the fixture 400, and the centerline of the clamp 500 is positioned to intersect the centerline of the start / end position of the DED string / wall of the preform 600 as much as possible (shown as clamp entities 610, 615, 620, 625, and 630). Such substrate clamp restraint can significantly reduce the deformation effects mainly resulting from the longitudinal residual stress during deposition. Non-optimal clamps can result in local deformation or buckling due to the lack of clamp restraint, as shown by the contour 650 of the dashed box.

[0266] For DED processing, different clamp arrangements can be used during pre-bending and when attaching the pre-bent substrate to the fixture. The difference in clamp arrangements can be selected because when applying thermal energy to the back side of the substrate using a melting tool that provides the DED heat source during pre-bending, it is necessary to increase the access of the heat source to the entire length or substantially the entire length of the substrate to produce a uniform deflection along the length of the longest substrate. Insulating clamps may not be used at the edges to allow the melting tool that provides the DED heat source to apply thermal energy to the entire length of the substrate. During the construction of an object by metal deposition on the front side of the substrate, insulating clamps can be placed at the periphery of the substrate, particularly at the start / end position of the DED wall, to help reduce local deformation resulting from the development of residual stress. The clamp configuration can (1) facilitate the symmetry of the entire plate, (2) use clamps of the same shape if possible, (3) enable the desired access to the substrate by the melting tool that provides the DED heat source, and (4) meet the torque requirements necessary to attach the pre-bent substrate to the fixture.

[0267] By using the mounting system 100, the manufacturing process can be significantly improved. However, by using a sheet of an insulating material such as a conventional alumina (Al2O3) insulating sheet or plate that is cut to form a curvature that substantially matches the arcuate degree of the pre-bent substrate, it is possible to perform the DED process on the front side of the pre-bent substrate. This is much more time-consuming than using the mounting system 100 provided herein. Further, there is variation in the thickness of the alumina insulating sheet, and since the layers of the pre-cut sheets are formed to match the curvature of the pre-bent substrate, there may be variation between workpieces. The various mounting systems 100 provided herein can reduce or prevent such variation between components by providing a structure having consistent physical and mechanical properties that can be used multiple times. Further, in the example, the mounting system 100 can exclude ceramic sheets, plates, or pylons, and thus can provide the additional advantage of less moisture in the DED atmosphere.

[0268] 3. Preheating of the substrate Once the pre-bent substrate is fixed to the jig using the mounting system 100 and the insulating clamp, the pre-bent substrate can be preheated before starting the DED process. This preheating step is intended to treat most of the surface on the front side of the substrate with a heat source to uniformly heat the entire substrate to a target temperature, and then build the workpiece using the DED process while the pre-bent substrate is still hot.

[0269] In the preliminary bending step, a steep thermal gradient and a high cooling rate are selected to generate higher internal tensile and compressive stresses, and in contrast to the application of energy to the back side of the substrate, in the preheating step, energy is applied to the front side of the substrate in a more gentle and consistent manner. During the preheating step, energy can be directed to the front side of the substrate using a heat source under conditions where the substrate surface is not locally melted. During the preheating step, energy can be directed to the front side of the substrate using a heat source under conditions where continuous melting tracks are not formed. Since nearly uniform heating is desired, the energy from the heat source can be applied at a relatively low speed of the melting tool providing the heat source, and the melting tool providing the heat source is positioned at a greater stand-off distance (farther from the substrate) to apply thermal energy at a lower energy density. Further, since the preheating step is intended to heat the substrate prior to workpiece construction using a DED process, no cooling gas is applied using a gas jet device. Thus, the cooling rate is significantly lower than the cooling rate that can occur in the preliminary bending step.

[0270] This slow heating / cooling cycle during preheating can promote slow cooling rates and low thermal gradient formation in the substrate along the x, y, and z directions. Since heat can dissipate throughout the volume of the preliminarily bent substrate by conduction, the application of energy during preheating can be done in a way that allows for the slow accumulation of residual heat. For example, a lower energy density can be used to impart a lower thermal gradient to the substrate. These conditions generate a “nearly” uniform temperature distribution across the base plate, allowing for the slow accumulation of residual heat as heat dissipates throughout the base plate volume by conduction. The preliminarily bent substrate is thermally isolated from the mount system 100, and an insulating clamp is used to secure the preliminarily bent substrate to the fixture, so that the residual heat can be more readily retained by the substrate.

[0271] The low energy density can be supplied to the substrate in a continuous manner to generate a substantially uniform temperature distribution across both the surface and the thickness of the substrate. To avoid exposing an area to accumulated thermal energy, the application of energy can start at a first edge of the substrate and continue across the surface of the substrate along the x-direction until it reaches a second edge on the opposite side of the substrate. Thereafter, the melting tool providing the heat source can be returned to the first edge and repositioned in the y-direction a certain distance away from the first energy application path, and energy can be applied along the x-direction. This process is repeated until the temperature of the pre-bent substrate reaches the target temperature. The more uniform the temperature distribution of the substrate, the more suitable it is for reducing the effects of stress and strain generated in the substrate.

[0272] An exemplary pattern of energy application during preheating is shown in FIG. 11. The black fading arrows indicate the direction / path of the DED energy source, and X ES The circles containing represent a sequence X where X is 1 to 8 across the surface of the second side 320 of the substrate 300. S indicates the starting point of the energy application path that brings about the heating path, and E indicates the end point of the path. In the pattern shown, heating is started at the bottom edge across the x-direction (1 ES ), then the heat source is moved in the y-direction to a point approximately one-ninth above the first heating path, and heat is applied in the y-direction from short side to short side (2 ES ). This procedure is repeated for 3 ES , 4 ES , 5 ES , 6 ES , 7 ES , and 8 ES until heat is applied across the entire surface of the substrate 300. The first heating path 700 corresponds to 1 ES . The second heating path 705 corresponds to 2 ES . The third heating path 710 corresponds to 3 ES . The fourth heating path 715 corresponds to 4 ES . The fifth heating path 720 corresponds to 5 ES . The sixth heating path 725 corresponds to 6 ES . The seventh heating path 730 corresponds to 7ES corresponds to. The eighth heating path 735 corresponds to 8 ES corresponds to. A single energy source or multiple energy sources can be used for the preheating path. The figure shows solid and dashed black disappearing lines representing the tool paths and preheating sequences of two melting tools operating in parallel. The illustrated embodiment describes heating using a DED energy source, but other energy sources can also be used. Exemplary alternative energy sources include, for example, one or more lasers, one or more induction heaters, or any combination of lasers, DED energy sources, and induction heaters. Furthermore, other methods and apparatuses capable of uniformly heating the base plate, such as induction heating, resistance heating, etc., can also be used.

[0273] The direction of preheating can be the same as the actual DED process for forming the preform so that the temperature and residence time in the area under the DED deposition area can be similar. For example, as shown in FIG. 11, the start position (S) and end position (E) of the preheating thermal energy application (indicated by the black disappearing arrows and each labeled by a circle) are in the same direction of metal deposition during the DED process.

[0274] Thermal energy application can be applied using any source that generates thermal energy. For example, electric arc-based, laser beam, and electron beam heat sources can be used alone or in combination to achieve the preheating effect. For example, one or more thermal arc welding sources, such as a preheating PTA torch and a melting PTA torch, can heat the substrate by traversing it laterally. The PTA torch can be positioned to reduce the formation of temperature gradients and shorten the total preheating time. Other heat sources based on laser energy or electron beam energy can also be used for the same purpose, but an appropriate parameter set is used to achieve similar heating of the substrate. The spacing between the preheating thermal energy application areas can depend on the amount of heat supplied by the heat source. The spacing between the preheating thermal energy application areas can depend on the heat distribution supplied by the heat source.

[0275] For example, two PTA thermal electric arc welding torches can be used to simultaneously traverse horizontally across a substrate to heat it. The two torches can have a relative (fixed) distance from each other, such as about 20 mm to 40 mm. This configuration can apply thermal energy along the x-direction and across the y-direction so that heat is supplied and spread as uniformly as possible without overlapping the centerlines of the heat sources. On the other hand, in the case of a fixed substrate width, when using a more concentrated heat source such as laser energy or electron beam energy for this purpose, the amount of preheating can be made different. The spot of the laser or electron beam can be designed to be larger so as to affect a wider heating area on the substrate. The substrate can also be uniformly heated by other methods and apparatuses including induction heaters and resistance heaters.

[0276] The melting tool providing the DED heat source can be used to perform uniform preheating. The positioning, sequence, and parameters used to perform preheating using the melting tool providing the DED heat source can be controlled such that the application of energy to the substrate results in the generation of a lower thermal gradient than that imposed on the substrate during the pre-bending step. The preheating can be performed to uniformly increase the temperature of the substrate. In an exemplary embodiment, the preheating can be performed to uniformly increase the temperature of the substrate to a temperature in the range of about 350 °C to about 650 °C, depending on the material of the substrate. For example, a substrate containing Ti can be preheated to a temperature in the range of about 400 °C to about 550 °C. For some Ti alloys, the substrate can be preheated to a temperature in the range of about 450 °C to about 500 °C to reduce the formation of thermal gradients during DED. The preheating can reduce the accumulation of internal stress during DED processing by reducing the local stress caused by heating when depositing molten metal to build the workpiece. By preheating the substrate to a high temperature such as the warm forming temperature or the hot forming temperature, as a result of the formation of weld beads on the substrate during DED workpiece formation, the resulting thermal gradient can be significantly smaller than the thermal gradient generated in the thickness direction when depositing welds on the substrate at room temperature, resulting in a strain close to zero. The preheating does not significantly modify or fuse the substrate surface and can result in the formation of a weld line without adding metal.

[0277] For preheating, indirect heating can be used, such as heating a pre-bent substrate clamped to a fixture in an oven to uniformly increase the temperature of the substrate. In some applications, this is not feasible or practical. The time required to move the combination of the substrate and the fixture from the oven to the chamber where the DED process can be performed can lead to a significant loss of residual heat from the substrate, defeating the purpose of the preheating step. This system can be modified to include an oven accessible through the deposition chamber so that the oven can be used to preheat the substrate.

[0278] Direct heating can be used that employs a heating device positioned to apply heat across the entire surface of the substrate when the substrate is attached to the fixture. Any method and heating device that can uniformly heat the substrate prior to deposition can be used. The heating device can be, or can include, an induction heater, a resistance heater, or a combination thereof. Exemplary heating devices include heaters that can include a conductor-in-conduit heat source, a heater strip, a resistive heating strip, an infrared heater, a positive temperature coefficient ceramic heater, a thick film ceramic heater, a resistance wire or ribbon heating device, and an induction heater, and any combination thereof.

[0279] 4. DED Process for Building a Workpiece Immediately after the substrate is preheated to the target temperature, a DED process can be performed to form a workpiece on the substrate. During construction of an object by metal deposition on the front side of the substrate, clamps can typically be positioned at the start / end positions of the DED wall to help reduce local deformations resulting from the development of residual stresses.

[0280] Prior to preheating, a pre-bent substrate can be brought into contact with the mount system 100 via an insulating / non-insulating clamp attached to the fixture. In an example, the substrate can be thermally separated from the fixture. In an example, the mount system 100 may not include ceramic or may include an insulating ceramic coating on a surface that can contact the pre-bent substrate. The pre-bent substrate does not adhere to the mount system. Further, as can be seen from this arrangement, a workpiece can be built on the surface of the pre-bent substrate while the pre-bent substrate is fixed to the fixture. While the pre-bent substrate may be part of the workpiece, no part of the mount system 100 is part of the workpiece.

[0281] The preliminarily bent substrate has an arcuate degree and is coupled to a mounting system having the same arcuate degree. However, the curvature inclination of the preliminarily bent substrate fixed to the jig using the mounting system as a support between the preliminarily bent substrate and the jig does not affect the overall deposition conditions. The radius of curvature of the curvature profile defined by the mounting system can be made large enough so that the influence of gravity does not adversely affect the mechanics of the weld pool, and the deposition on the preliminarily bent substrate in contact with the mounting system can obtain the same results as when depositing on a substrate in a flat position. The radius of curvature of the curvature profile defined by the mounting system can be selected so that the influence of gravity due to the inclination does not affect the behavior of the liquid melt pool deposited or formed on the surface of the preliminarily bent substrate. Further, the controller used in the DED process for constructing the workpiece can adapt the z coordinate to the curvature of the curvature profile defined by the mounting system to ensure that consistent energy / processing conditions are supplied by the DED process during the manufacture of the workpiece. The CAD-CAM program instructions can be executed to result in a melting tool that provides a DED heat source according to the exact shape of the curvature profile defined by the mounting system to ensure that the overall processing conditions, particularly the standoff distance, are not affected.

[0282] The design of a workpiece constructed by the DED process can be positioned on the front side of the substrate such that most of the walls of the workpiece formed by the deposition of molten metal are between adjacent melt tracks on the back side of the substrate and preferably equidistant from the adjacent melt tracks. This positioning allows non-uniform plastic deformation and high tensile stresses that can occur in the melt region during DED manufacturing of the workpiece to occur in the area of high compressive stress imposed by the pre-bending process, and the compressive stresses that can form as the welds of the workpiece cool can occur in the area of high tensile stress imposed by the pre-bending process. Thus, by positioning the walls of the workpiece on the front side of the substrate relative to the melt tracks on the back side of the substrate, the residual stress field can be balanced and the total strain of the as-deposited preform can be reduced.

[0283] An exemplary deposition pattern for preform formation is shown in FIG. 11. As shown, most of the walls, such as 380, 382, and 384, of the workpiece preform 600 formed by the deposition of molten metal are between adjacent pre-heating paths 700, 705, 710, 715, 720, 725, 730, and 735 on the back side or first side 310 of the substrate 300, and the preform 600 is positioned on the front side or second side 320 of the substrate 300 such that it is preferably equidistant from these. An exemplary DED sequence path for each layer is sequentially shown by boxes S1 - S5, and the arrows indicate the DED direction for each layer.

[0284] In a method of manufacturing a metallic workpiece using the DED process provided herein, a three-dimensional object of metallic material can be manufactured by fusing successive deposits of metallic material onto a substrate. Any DED process can be used for constructing the workpiece. The DED process can use one or more melting tools that provide an energy source, either alone or in combination. Exemplary melting tools that can be used include a PTA torch that provides an electric arc plasma as a heat source, a laser device that provides a laser beam as a heat source, an electron beam device that provides an electron beam as a heat source, and any combination thereof. In some configurations, more than two melting tools that provide a heat source can be used. For example, one melting tool that provides a DED heat source can be used to preheat the substrate, and a second melting tool that provides a DED heat source can be used to melt the metallic material and form a molten metal that can be deposited onto the preheated area. If multiple melting tools that provide a DED heat source are used, they can be the same or different from each other. Exemplary combinations of multiple melting tools include two PTA torches, two laser beam devices, two electron beam devices, a PTA torch and a laser beam device, a PTA torch and an electron beam device, and a laser beam device and an electron beam device.

[0285] In some methods, the first melting tool can be used to supply energy to at least a portion of the surface of the base material, for example, the location where the metal material is deposited, for surface heating of the substrate. This is different from a preheating step to raise the temperature of the entire substrate to a target temperature to minimize the thermal gradient during the DED process. In contrast, whether it is the substrate or a previously deposited metal layer, for surface heating of the base material, the first melting tool supplies high-intensity energy to a limited area of the base material and raises the temperature of the base material in the energy application area to a temperature slightly lower than the melting temperature, for example, 0.1% - 10% lower than the melting temperature, or to the melting temperature. Surface heating of the base material can improve the wetting and spreading characteristics of the weld bead. Surface heating of the base material can improve the contact angle of the weld bead. Surface heating of the base material can make the surface more receptive to the molten metal deposited on the heated surface.

[0286] The metal material can be heated and melted using a second melting tool such that the molten metal material is deposited on the surface heating area of the base material heated by the first melting tool. A gas jet device can be used to direct the cooling gas over the entire surface of the liquid melt pool, or impinge the cooling gas on the surface of the liquid melt pool, or on the surface of the solidified material adjacent to the liquid-solid boundary of the liquid melt pool, or any combination thereof. The base material can be relatively moved with respect to the positions of the first and second melting tools and the gas jet device in a predetermined pattern such that a continuous deposit of the molten metal material solidifies to form a three-dimensional workpiece. Alternatively, the first and second melting tools and the gas jet device can be relatively moved with respect to the position of the base material in a predetermined pattern such that a continuous deposit of the molten metal material solidifies to form a three-dimensional workpiece.

[0287] In the method provided herein, the cooling gas can be an inert gas such as argon, helium, neon, xenon, krypton, and combinations thereof, or can include these inert gases. The cooling gas can have a flow rate measured at the inlet of about 1 L / min to about 300 L / min. The cooling gas can be applied in a continuous stream, intermittently, or in a pulsed flow. The flow of the cooling gas can be adjusted to create turbulence of the cooling gas near the melt pool. For example, the velocity of the cooling gas flowing through the gas jet device can be increased so that the cooling gas exiting the gas jet device exhibits turbulent flow rather than laminar flow. The cooling gas can be supplied using multiple nozzles on a single gas jet device or using multiple gas jet devices so as to direct a combination of laminar and turbulent flows of the cooling gas towards the vicinity of the melt pool.

[0288] The temperature of the applied cooling gas can be any temperature. The cooling gas temperature can be the ambient temperature of the chamber in which the layer forming process is carried out. The cooling gas temperature can be below room temperature, for example, about 25°C or below. The cooling gas can be at a refrigerated temperature such as about -150°C to about 4°C, or about -10°C to about 10°C.

[0289] The number and configuration of the nozzles of the gas jet device, and / or the number of gas jet devices, and their configuration and arrangement can be selected to supply a cooling gas that covers the length of the workpiece, such as a distance of about 5 mm to about 50 mm, or about 10 mm to about 40 mm, or about 15 to about 30 mm along the direction of movement, in the thermal energy collision area or its periphery.

[0290] In the method provided herein, a melting tool that provides a DED heat source can be used in combination with a gas jet device to control the melt pool conditions, and the gas jet device generates a cooling gas that results in a temperature drop from about 1200°C to about 600°C, or from about 1000°C to about 800°C. In some methods where the workpiece is formed of a Ti alloy, a temperature drop from 1000°C to 800°C can be used.

[0291] The methods provided herein can be implemented in any additive manufacturing system. The methods can be implemented in a system in which the inert gas includes only a heat source such as an electric arc plasma, or includes a molten tool including a heat source, or includes a molten tool and a workpiece. The methods can be implemented in a system including a sealed chamber filled with an inert gas to provide an inert atmosphere in which the entire process is carried out. The inert atmosphere can be or can include argon, xenon, neon, krypton, helium, or combinations thereof, enabling inert atmosphere deposition.

[0292] Exemplary differences between a conventional substrate configuration for a DED process and the process provided herein using a mounting system 100 implemented as a pin support system 110 are shown in FIGS. 12A and 12B. FIG. 12A shows a conventional configuration viewed in the y-direction in which a substrate 300 is fixed to a jig 400 (via a clamp not shown) but thermally isolated from the jig 400 by alumina insulating plates 540, 541, 542, 543 positioned between the substrate 300 and the jig 400. The substrate 300 without stress relief treatment is flat, and a metal material is deposited on the upper surface of the substrate 300 during the DED process to produce preforms 600 and 600'.

[0293] In contrast, FIG. 12B shows an exemplary embodiment of a substrate configuration using a mount system 100 implemented as a pin support system 110 viewed in the y-direction for comparison with the illustration of FIG. 12A. FIG. 12C shows an exemplary embodiment of a substrate configuration using a mount system 100 implemented as the pin support system 110 of FIG. 12B, but is a view in the x-direction to illustrate that the preform 600 can be deposited along the length of the substrate 300. In the configuration shown, the pin support system 110 can function as a support that lies under the substrate 300 when the substrate 300 is fixed to the fixture 400 (via a clamp not shown). Since the pin support system 110 can be configured such that the mount system 100 thermally isolates the substrate 300 from the fixture 400, it is possible to eliminate the need to use an alumina insulating plate or other substrate support fixtures that have conventionally been used to thermally separate the substrate from the fixture. The substrate 300 is subjected to the stress reduction process disclosed herein, and as a result, preliminary bending of the substrate 300 can occur. The preliminarily bent substrate 300 can be clamped to the pin support system 110 using an insulating clamp (not shown). In an example, the radius of curvature of the curvature defined by the pin support system 110 can be made large enough so that the influence of gravity does not adversely affect the mechanics of the weld pool, whereby the deposition is achieved in the same manner as when depositing in a flat position. The metal material is deposited on the upper surface of the substrate 300 during the DED process to manufacture the preforms 600 and 600'.

[0294] D. System Also provided is a system for constructing a metal workpiece by a DED process. This system includes a jig to which a preliminarily bent substrate is fixed; a mount system 100 that can function as a support lying under the preliminarily bent substrate when the preliminarily bent substrate is fixed to the jig; an insulating clamp for fixing the preliminarily bent substrate to the jig; one or more melting tools comprising a DED energy source for melting a metal source to form a metal melting material that can be deposited on the surface of a base material (in the first layer, the base material is the surface of the substrate; in subsequent layers, the base material is the surface of a previously deposited metal layer); a gas jet device capable of directing a cooling gas across a liquid melt pool, or a cooling gas impinging on the liquid melt pool, or a cooling gas impinging on a solidified material adjacent to the liquid-solid boundary of the liquid melt pool, or any combination thereof; a supply section for the cooling gas; a system for positioning and moving the base material relative to the melting tool and the gas jet device; and a controller capable of reading a design model such as a computer-aided design (CAD) model of the metal workpiece to be formed, using the design model to adjust the position and movement of the said system for positioning and moving the base material, and operating the melting tool and the gas jet device such that the workpiece is constructed by fusing a metal material onto the base material to form a continuous deposition of the metal material forming the workpiece.

[0295] A single melting tool can be used, or two melting tools can be used. For example, a first preheating torch that generates a single preheating electric arc plasma and a second torch that generates a double electric arc plasma. The two torches can be used simultaneously in a tandem configuration. The preheating arc can supply thermal energy to a part of the surface of the base material for surface heating of the substrate or preconditioning, for example, at the position where the metal DED material is deposited. Further, the double electric arc plasma can be powered by a separate power supply unit. The double electric arc plasma can be used to resistively heat the metal and melt it onto the surface heating area of the base material. The double electric plasma arc can ensure sufficient fusion between the base material of the workpiece and the molten metal generated by the action of the electric arc plasma arc on the metal such as the metal wire feedstock. For example, the second melting tool can be a torch that generates a double electric arc plasma, whereby one arc burns between the tungsten electrode of the torch and the workpiece (PTA), and the other arc burns between the tungsten electrode of the torch and the wire feedstock (main arc), both using straight polarity. The PTA electric arc plasma can deepen the fusion characteristics of the molten metal into the preheated surface of the base material, which can be controlled independently of the main electric arc plasma. The main electric arc plasma can be established between the torch and the wire feedstock through which the current flows. The wire feedstock can be melted by the heat generated by the column of the PTA electric arc plasma transmitted to the workpiece and the heat generated by the main electric arc plasma circuit. The wire feedstock can generate molten metal that can be deposited onto the workpiece. Due to the superheat from the droplets of the molten metal, a molten pool can be maintained near the surface heating area of the base material. By heating the surface of the base material, the fusion is improved, the wetting and spreading characteristics of the liquid pool are improved, and thus overall better DED characteristics can be obtained. Regarding the deposition profile, it may be possible to obtain a shallower and wider deposition profile by heating the surface of the substrate.The improved weld bead characteristics result in a shape with a beneficial weld bead contact angle with respect to the base material, thereby facilitating sufficient fusion to the base material and the adjacent weld bead. When the characteristics of the weld bead and fusion are improved, a product with improved mechanical integrity can be obtained.

[0296] Each melting tool can be controlled separately and thus adjusted individually to produce separate fields of temperature and pressure. The advantage of this arrangement can be that the amount of thermal energy applied to the metal feedstock melted on the surface heating area of the base material can be made greater than the thermal energy applied to the surface of the base material, avoiding overheating of the base material.

[0297] The DED manufacturing system provided herein can include, as melting tools, a PTA torch, a laser device, an electron beam device, or any combination thereof. In some configurations, a first PTA torch electrically connected to the base material surface heats a target deposition area on the base material to form a surface heating area, and a second PTA torch electrically connected to the consumable electrode heats and melts the consumable electrode, resulting in droplets of molten metal that can fall onto the surface heating area of the target deposition area. In some configurations, the PTA torch can surface heat a target deposition liquid area on the base material to form a surface heating area, the laser device can heat and melt a metal wire or metal powder, resulting in the formation of molten metal that can be deposited onto the surface heating area of the target deposition area. In some configurations, the PTA torch can heat a target deposition area on the base material to form a surface heating area, and the electron beam device can heat and melt a metal wire, resulting in droplets of molten metal that can fall onto the surface heating area of the target deposition area.

[0298] In some configurations, the laser device can spot heat a target deposition area on a base material to form a spot-heated area, and the PTA torch electrically connected to the consumable electrode can heat and melt the consumable electrode, and as a result, can produce droplets of molten metal that can fall onto the spot-heated area of the target deposition area. In some configurations, the first laser device can spot heat a target deposition area on a base material to form a spot-heated area, and the second laser device can heat and melt a metal wire or metal powder, and as a result, can produce the formation of molten metal that can be deposited on the spot-heated area of the target deposition area. In some configurations, the laser device can spot heat a target deposition area on a base material to form a spot-heated area, and the electron beam device can heat and melt a metal wire, and as a result, can produce droplets of molten metal that can fall onto the spot-heated area of the target deposition area.

[0299] In some configurations, the electron beam device can spot heat a target deposition area on a base material to form a spot-heated area, and the PTA torch electrically connected to the consumable electrode can heat and melt the consumable electrode, and as a result, can produce droplets of molten metal that can fall onto the spot-heated area of the target deposition area. In some configurations, the electron beam device can spot heat a target deposition area on a base material to form a preheated area, and the laser device can heat and melt a metal wire or metal powder, and as a result, can produce droplets of molten metal that can fall onto the spot-heated area of the target deposition area. In some configurations, the first electron beam device can spot heat a target deposition area on a base material to form a spot-heated area, and the second electron beam device can heat and melt a metal wire or metal powder, and as a result, can produce droplets of molten metal that can fall onto the spot-heated area of the target deposition area.

[0300] In some configurations, a DED manufacturing system can include a laser device or a PTA torch that can be arranged to direct energy (e.g., laser energy or a plasma transferred arc, respectively) at a target area of a base material to form a surface heating area, and the PTA torch or laser device can be arranged to direct energy at an end of a consumable electrode or a metal wire positioned above the surface heating area of the base material. The energy can melt the end of the consumable electrode or metal wire and form droplets of molten metal that can fall onto the surface heating area of the base material beneath the end of the consumable electrode or metal wire. A melting tool that directs energy at a target deposition area can promote the fusion of the base material with the molten metal material deposited thereon by deepening the penetration of the droplets of molten metal into the base material. The melting tool used to melt the consumable electrode or metal wire can also contribute thermal energy in the vicinity of the spot heating area of the target deposition area, contributing to the thermal energy provided by the melting tool directed at the base material. The superheat from the droplets of molten metal can help maintain a melt pool in the vicinity of the spot heating area of the base material.

[0301] The consumable electrode or metal wire is, or can include, Al, Cr, Cu, Fe, Hf, Sn, Mn, Mo, Ni, Nb, Si, Ta, Ti, V, W, or Zr, or a composite material or alloy thereof. In some embodiments, the consumable electrode can be a wire containing Ti or a Ti alloy. The consumable electrode or metal wire is, or can include, a titanium alloy that combines Ti with one or a combination of Al, V, Sn, Zr, Mo, Nb, Cr, W, Si, and Mn. For example, exemplary titanium alloys include Ti-6Al-4V, Ti-6Al-6V-2Sn, Ti-6Al-2Sn-4Zr-6Mo, Ti-45Al-2Nb-2Cr, Ti-47Al-2Nb-2Cr, Ti-47Al-2W-0.5Si, Ti-47Al-2Nb-1Mn-0.5W-0.5Mo-0.2Si, and Ti-48Al-2Nb-0.7Cr-0.3Si. The consumable electrode or metal wire can include aluminum, iron, cobalt, copper, nickel, carbon, titanium, tantalum, tungsten, niobium, gold, silver, palladium, platinum, zirconium, alloys thereof, and combinations thereof. The consumable electrode can include a solid wire electrode, a cored wire electrode, or a strip electrode.

[0302] A typical cross-section of the consumable electrode or metal wire is circular. The diameter of the consumable electrode or metal wire is up to about 10 mm and can range from about 0.8 mm to about 5 mm. The consumable electrode or metal wire can have any cross-sectional dimension that is practically feasible, such as 1.0 mm, 1.6 mm, and 2.4 mm, or from about 0.5 mm to about 3 mm. The feed rate and positioning of the consumable electrode or metal wire are controlled and adjusted in accordance with the effect of the power supply to a PTA torch, a laser device, an electron beam device, or any combination thereof to ensure that the consumable electrode or metal wire is continuously heated and melted when it reaches the intended position above the preheating area of the base material.

[0303] The laser device can generate a laser beam with sufficient energy to transfer thermal energy to the base material to preheat the surface area of the base material or to melt the metal wire. Preheating the base material via the energy from the laser beam can promote the fusion between the base material and the molten metal material by deepening the melting characteristics in the base material. In some embodiments, at least a portion of the base material can be melted by the energy from the laser beam of the laser device. In some embodiments, sufficient heat can be applied by the laser beam of the laser device to form a molten pool in the base material at the location where the metal material produced by a PTA torch, or another laser device, or an electron beam device is to be deposited.

[0304] Examples of suitable laser devices include ytterbium (Yb) lasers, Yb fiber lasers, Yb fiber-coupled diode lasers, Yb:glass lasers, diode-pumped Yb:YAG lasers, neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers, CO2 lasers, CO lasers, Nd:glass lasers, neodymium-doped yttrium orthovanadate (Nd:YVO) lasers, Cr:ruby lasers, diode lasers, diode-pumped lasers, excimer lasers, gas lasers, semiconductor lasers, solid-state lasers, dye lasers, X-ray lasers, free-electron lasers, ion lasers, gas-mixture lasers, chemical lasers, and combinations thereof. Preferred lasers include Yb lasers, particularly Yb fiber lasers. In many applications, the wavelength used in Yb fiber lasers can have a lower reflectivity compared to other laser wavelengths.

[0305] A PTA torch can be of any configuration capable of generating an electric arc plasma for resistively heating and melting a consumable electrode, such as in gas metal arc welding (GMAW), particularly welding using a non-reactive gas to establish the arc (metal inert gas welding or MIG welding), or for heating a target area on the surface of a base material. The consumable electrode can be melted in the plasma generated by a PTA torch using an electric arc, and the molten consumable electrode can be deposited into a molten pool on the workpiece to add to and form a near-net shape metallic body. Preheating of the base material via energy from the PTA torch can promote fusion between the base material and the molten metal material by deepening the melting characteristics in the base material. In some embodiments, at least a portion of the base material can be melted by energy from the plasma of the PTA torch. In some embodiments, sufficient heat can be applied by the plasma of the PTA torch to form a molten pool in the base material at the location where a metallic material melted by a different PTA torch or laser device is to be deposited.

[0306] By a combination of thermal pre-bending of the substrate by inducing a melt track, use of the mount system 100, and preheating of the substrate prior to forming a workpiece using a DED process, it is possible to form a near-net shape metallic workpiece that significantly reduces problems associated with significant internal residual stresses and distortion in many conventional additive manufacturing products. Thereby, it is possible to manufacture a workpiece with improved manufacturing reproducibility, improved dimensional accuracy, and improved strength, fatigue resistance, and durability.

Example

[0307] E. Example The following examples are included for illustrative purposes only and are not intended to limit the scope of the embodiments provided herein.

[0308] Example 1 A first base plate substrate made of Ti-6Al-4V with dimensions (L×W×T) of 635 mm×190 mm×9.5 mm was used as a first test substrate to measure deflection without reducing residual stress. The substrate was clamped to a jig or welding table, the base material was preheated with a first PTA torch, and a Ti-6Al-4V wire was melted with a second PTA torch to form a molten metal, which was deposited on the preheated base material to fabricate a workpiece. The deposition rate was 7.5 - 10 mm / s, and an inert gas was used to direct the cooling gas at a high flow rate to impinge on the solidified material adjacent to the liquid-solid boundary of the liquid melt pool. After the deposition was completed, the components were cooled and removed from the jig, and the deformation of the substrate was examined.

[0309] Strain was observed on the short side of the substrate, and the substrate was bent upward in an arcuate shape compared to the flat profile of the substrate before deposition. The observed deformation is shown in Fig. 13A.

[0310] A second base plate substrate made of Ti-6Al-4V with dimensions (L×W×T) of 635 mm×190 mm×12.7 mm was used as a second test substrate. Using the same conditions as described above, the same workpiece was fabricated. Fig. 13B shows the deformation caused by DED deposition on a substrate with a thickness of 12.7 mm that has not undergone any kind of residual stress relief, showing an upward bow on the short side of the substrate and the left edge bending upward by about 7 mm and the right edge bending upward by about 6.0 mm compared to the flat profile of the substrate before deposition.

[0311] Figure 13C shows a third baseplate substrate made of Ti-6Al-4V that has dimensions (L×W×T) of 635 mm×190 mm×9.5 mm and was used in the formation of an object by being subjected to thermal pre-bending, pre-heating, and DED processing as described herein. The substrate was firmly clamped to the fixture using insulation clamps over the entire length of the long side of the substrate, but no clamps were used on the short side of the substrate. Four layers of alumina insulation plates (RS-1200 Keranova) with a thickness of approximately 3.2 mm and the same dimensions as the substrate were used between the substrate and the fixture to thermally isolate the substrate from the fixture.

[0312] A PTA torch was used to provide thermal energy to the first side of the substrate to form a molten track on the substrate. The final set residual stress distribution determined by the combination of DED and the molten track has a lower tensile peak at the centerline of the DED and a lower balancing compressive stress at positions away from the centerline of the DED compared to the original residual stress profile of the DED without a pre-bent molten track (i.e., with a high tensile peak at the centerline of the DED and a high balancing compressive stress at a distant position). The patterns used to form the molten tracks are shown in FIGS. 7C and 7D. As shown in the figures, a PTA torch functioning as a DED heat source was positioned at one edge of the substrate. The spacing between the molten tracks can be premised on the shape of the workpiece to be manufactured. For example, the molten tracks can be formed in areas other than the area under the wall of the workpiece to be formed to minimize the final set residual stress distribution within the workpiece. For example, most of the molten lines on the first surface can be formed at one or more positions other than the positions corresponding to one or more areas occupied by one or more walls of the workpiece formed on the second side of the substrate. To induce the maximum thermal stress in the substrate, a high energy density (e.g., arc energy supplied at about 450 J / mm to about 550 J / mm) was applied at a speed of 6 to 16 mm / s to rapidly melt a portion of the substrate surface to form a self-weld line, and this self-weld line was rapidly cooled using a gas jet device, directing a cooling gas at a temperature of 25 °C at a high flow rate towards the weld line, thereby forming a molten track having a high tensile stress near the centerline of the molten track and a high compressive stress at a distance from the centerline. In an exemplary embodiment, when the thickness of the substrate is 9.5 to 10 mm, a single heat source with a current of about 150 A to about 250 A, a voltage of about 20 V to about 30 V, and a traverse speed of 6 mm / s to 16 mm / s was used to form a molten track with a width of about 3 mm and a maximum depth of 1 mm.

[0313] When released from the jig, the pre-bent substrate bowed upward, showing a deflection of about 15 mm as shown in Fig. 8A. Next, this pre-bent substrate was attached to the jig using the curved clamp mold described as the support lying horizontally below and the insulating clamp, and the pre-bent substrate was attached to the jig. The pre-bent substrate was positioned such that the side with the molten track faced the curved clamp mold. The preheating of the pre-bent substrate was achieved by positioning the PTA torch at a higher stand-off distance in order to reduce the risk of generating local molten tracks that could cause fusion problems at the base plate interface during DED metal deposition, and by using two PTA torches that supply a lower energy density to the surface of the pre-bent substrate. For example, preheating was performed using two PTA torches with a range of 150 - 250 A and an arc voltage of 20 - 30 V. The traverse speed was 6 - 12 mm / s. For example, the arc energy supplied by the first PTA torch could be 460 J / mm, and the arc energy supplied by the second PTA torch could be 430 J / mm. Another important aspect is the fact that the pre-bending of the track was carried out with a higher plasma gas flow compared to that used for preheating. The higher plasma gas flow rate generates a harder electric arc, resulting in a higher energy density. Regarding the stand-off distance, during preheating, a stand-off distance 25% - 50%, or 30% - 40% higher than that used in pre-bending can be used. No cooling gas was used during the preheating process.

[0314] After the temperature of the substrate reached 450°C to 550°C, DED deposition of the metal for forming the object was performed in a sealed chamber containing an argon inert atmosphere. The DED process used two PTA torches. The first PTA torch directed thermal energy towards the target area of the base material to form a preheating area, and the second PTA torch directed thermal energy (1) towards the end of a consumable electrode or metal wire positioned above the preheating area of the base material and (2) towards the preheating area. The energy from the second PTA torch melted the end of the consumable electrode or metal wire, forming droplets of molten metal that fell onto the preheating area of the base material under the end of the consumable electrode or metal wire. This process also included using a gas jet device to direct a high flow rate of cooling gas at a temperature of 25°C towards the solidified material adjacent to the liquid-solid boundary of the molten metal. The deposition was continued until the workpiece was completed. The workpiece was cooled to a temperature of 400°C or less in the deposition chamber. Thereafter, the workpiece was removed from the deposition chamber, and the pre-bent substrate was removed from the jig. Depending on the speed at which the operator removes the workpiece, the pre-bent substrate can be removed from the jig at a temperature of 200 to 300°C, or lower. In this example, the pre-bent substrate was removed from the jig at a temperature of approximately 250°C.

[0315] As shown in Figure 13C, the workpiece showed a slight upward movement (about 0.5 mm) at the short side of the substrate, indicating that a significant amount of residual stress observed in the test substrate when using the conventional DED process was removed using a curved clamping die combined with pre-bending and pre-heating.

[0316] Using the same substrate and the same workpiece design as above, reproducibility was tested under the same conditions as described above. This method showed consistent and reproducible results across all three workpieces produced. The deviation in substrate deformation between workpiece #1 and workpiece #2 was about 0.5 mm, and the deviation in substrate deformation between workpiece #2 and workpiece #3 was about 0.1 mm.

[0317] The stress relaxation heat treatment did not significantly affect the overall dimensions of the workpiece. For example, after stress relaxation, only a slight upward movement of about 0.5 mm occurred at the short side of the plate. This means that as a result of the described stress reduction, the residual stress of the workpiece in the as-deposited state was very low.

[0318] Example 2 A comparative experiment was conducted to compare the temperature gradient of the substrate during DED manufacturing when using a ceramic sheet support known in the art and when using the pin support system described herein. The same DED manufacturing process was performed on two equal titanium substrates. In the first example, during the DED process described herein, the substrate was clamped to a set of pins. On the other hand, in the second example, during the DED process described herein, the substrate was clamped on top of a set of ceramic pylons. The overall thickness of the ceramic pylons was greater than the substrate support height of the pins. Thermocouples were used to measure heat conduction and the heat of various components. Data were collected and plotted across various positions of the substrate being processed. The results are shown in Figure 15. As shown, the average rotational temperature of the substrate during the DED process clamped to a set of pins remained higher throughout the DED process than when the substrate was clamped to a set of ceramic pylons. This indicates that the use of a pin support system as described herein as a support structure may result in a reduction in heat loss from the substrate compared to known ceramic pylon supports.

[0319] Example 3 For a support formed of a ceramic pylon, a comparative experiment was also conducted to demonstrate the reduction in the amount of moisture achieved during the DED process when using a support system that does not include a ceramic sheet, plate, or pylon, such as the pin support system described herein. In the example, the DED process was performed on two equal substrates in the same manner as in Example 2. During the first experiment, the substrate was clamped to the pin support system described herein that does not include a ceramic sheet, plate, or pylon. During the second experiment, the substrate was clamped to the ceramic pylon support. The moisture and oxygen content in the atmosphere were monitored, and the measured values are reflected in FIG. 16A when the substrate was supported by the ceramic-free pin support system and in FIG. 16B when the substrate was supported by the ceramic pylon. This measurement data shows that the amount of moisture in the DED atmosphere is much lower throughout the process when using the pin support system described herein without using any ceramic sheet, plate, or pylon, compared to when using a ceramic pylon support.

[0320] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Accordingly, the present invention is intended to cover modifications and variations of the present invention provided they come within the scope of the appended claims and their equivalents.

[0321] The following is a list of reference numbers used in this description and the accompanying drawings.

Description of the reference signs

[0322] 100 Substrate mounting system 101 Mounting system element 102 Mounting system bending profile 103 Knurling 104 Peripheral rim portion 105 Knurling interval 106 Mounting system substrate interface area 107 Bond coat 108 Ceramic Coating 110 Pin Support System 112 Pin 114 Pin with Uniform Width 115 Pin with Non-Uniform Width 116 Pin with Combined Shape 118 Pin Head Portion 119 Pin Substrate Contact Surface 120 Pin Head Flat Region 122 Color Portion of Pin 124 Pin Base or Engagement Portion 126 Welding Fixture Joint for Pin Structure 128 Pin Spacer 130 Substrate Interface Area of Pin Support System 150 Lattice Support System 151 Lattice Element 152 Curved Surface of Lattice Support System 153 Flat Surface of Lattice Support System 154 Peripheral Area of Lattice Support System 155 Substrate Surface Interface of Lattice Support System 156 Lattice Element Substrate Contact Surface 158 Lattice Cavity 170 Curved Clamping Die 172 Knurling or Corrugated Surface 174 Upper Surface / Substrate Interface Area 176 Die Edge 178 Knurling 180 Knurling Interval 182 Flat Rim 184 Ceramic Coating 186 Bond Coat 188 Cavity 190 Cavity 192 Cavity 194 Cavity 196 Reinforcing Member 198 Maximum Height 200 Gas Jet Device 210 Nozzle 230 Support 250 PTA Torch 300 Substrate 310 First Side 320 Second Side 330 DED Rear Wall of the Preform 350 Melt Track 355 Spacing between Melt Tracks 370 First Pre-curved Heating Path 371 Second Pre-curved Heating Path Transmission Distribution 372 Third Pre-curved Heating Path 373 Fourth Pre-curved Heating Path 374 Fifth Pre-curved Heating Path 375 Sixth Pre-curved Heating Path 380 Preform Wall 382 Preform Wall 384 Preform Wall 400 Fixture 410 Nominal Substrate Deflection 500 Clamp 501 Screw Hole 502 Hole 505 Bottom Contact Facet 506 Side Contact Facet 540 Alumina Insulating Plate 541 Alumina Insulating Plate 507 Upper Surface of the Clamp 509 Ceramic Coating Surface 510 Pan Screw 515 Tip of the Pan Screw 520 Bolt 525 Nut 530 Upper Surface of the Fixture 542 Alumina Insulating Plate 543 Alumina Insulating Plate 544 Area of Non-uniform Pressure and Heat Transfer Distribution 545 Area of Non-uniform Pressure and Heat 546 Area of Non-uniform Pressure and Heat Transfer Distribution 547 Area of Non-uniform Pressure and Heat Transfer Distribution 548 Area of Non-uniform Pressure and Heat Transfer Distribution 549 Areas of non-uniform pressure and heat transfer distribution 550 Base plate 575 Frame indicating the area of non-uniform pressure and heat transfer distribution 576 Frame indicating the area of non-uniform pressure and heat transfer distribution 577 Frame indicating the area of non-uniform pressure and heat transfer distribution 578 Frame indicating the area of non-uniform pressure and heat transfer distribution 600 Preform 600’ Preform 610 Clamping entity 615 Clamping entity 620 Clamping entity 625 Clamping entity 630 Clamping entity 650 Non-optimal clamping area 700 First preheating heating path 705 Second preheating heating path 710 Third preheating heating path 715 Fourth preheating heating path 720 Fifth preheating heating path 725 Sixth preheating heating path 730 Seventh preheating heating path 735 Eighth preheating heating path

Claims

1. A first side configured to interface with a welding jig, and a second side defining a curved profile and configured to interface with a substrate, the second side including a substrate interface area sized to correspond to a surface of the substrate configured to interface with the second side, and a substrate contact area configured such that the mounting system physically contacts the substrate when the second side interfaces with the substrate, wherein the substrate contact area constitutes 0.1 to 20 percent of the substrate interface area, a mounting system.

2. The percentage of the substrate interface area constituted by the substrate contact area is a) 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 or more, and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or less, b) in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1, c) in the range of 0.1 to 15, 0.1 to 10, 0.1 to 5, or 0.1 to 1, d) in the range of 0.2 to 20, 0.2 to 15, 0.2 to 10, 0.2 to 5, or 0.2 to 1, e) in the range of 0.3 to 20, 0.3 to 15, 0.3 to 10, 0.3 to 5, or 0.3 to 1, f) in the range of 0.4 to 20, 0.4 to 15, 0.4 to 10, 0.4 to 5, or 0.4 to 1, g) in the range of 0.5 to 20, 0.5 to 15, 0.5 to 10, 0.5 to 5, or 0.5 to 1, h) in the range of 0.6 to 20, 0.6 to 15, 0.6 to 10, 0.6 to 5, or 0.6 to 1, i) in the range of 0.7 to 20, 0.7 to 15, 0.7 to 10, 0.7 to 5, or 0.7 to 1, j) in the range of 0.8 to 20, 0.8 to 15, 0.8 to 10, 0.8 to 5, or 0.8 to 1, or k) in the range of 0.9 to 20, 0.9 to 15, 0.9 to 10, 0.9 to 5, or 0.9 to 1, The mounting system according to claim 1.

3. The mounting system according to claim 1 or 2, further comprising a non-magnetic metal or a metal having a melting point of 1350° C. or higher.

4. The mounting system according to claim 3, wherein the metal includes austenitic stainless steel.

5. The mounting system according to claim 4, wherein the austenitic stainless steel contains carbon, chromium, copper, manganese, molybdenum, nickel, nitrogen, phosphorus, silicon, or any combination of two or more thereof.

6. The mounting system according to claim 4, wherein the austenitic stainless steel contains at least 18% chromium.

7. The mounting system according to claim 4, wherein the austenitic stainless steel is a 300 series stainless steel.

8. The mounting system according to claim 4, wherein the austenitic stainless steel includes 304 series stainless steel, 309 series stainless steel, 310 series stainless steel, 316 series stainless steel, 318 series stainless steel, 321 series stainless steel, or 330 series stainless steel.

9. The ceramic coating is zirconium dioxide, zirconium dioxide stabilized by the addition of yttrium oxide, yttrium aluminum oxide, alkaline earth metal silicate, ZrV ２ O ７ , Mg ３ (VO ４ ) ２ , or a combination thereof, the mounting system according to any one of claims 1 to 8.

10. The mounting system according to any one of claims 1 to 9, further comprising a nominal bending profile deflection of about 3 mm to about 35 mm.

11. The mounting system according to any one of claims 1 to 10, wherein the mounting system is reconfigurable.

12. The mounting system according to any one of claims 1 to 11, wherein the bending profile is defined by one or more pins.

13. At least a first pin of the one or more pins arranged to have a first substrate support height, Further comprising at least a second pin of the one or more pins arranged to have a second substrate support height, The first substrate support height is different from the second substrate support height, The mounting system according to claim 12.

14. The mounting system according to any one of claims 1 to 10, wherein the bending profile is defined by a bending clamp mold.

15. Comprising one or more pins in a reconfigurable arrangement on a welding jig, The one or more pins are arranged to have a variable substrate support height and define a bending profile, Pin support system.

16. At least one of the one or more pins, A pin head portion including a substrate contact area, A collar portion, And a base portion configured to engage with the welding jig. The pin support system according to claim 15.

17. The pin support system according to claim 15, wherein the pin head portion further includes a flat portion in at least a part of the lateral profile.

18. The pin support system according to claim 15, wherein the pin head portion includes a welding jig interface area.

19. The pin support system according to any one of claims 15 to 18, wherein the one or more pins include austenitic stainless steel.

20. A directed energy deposition method for manufacturing a metal workpiece, comprising: Pre-bending a substrate of a metal material with thermal energy by forming a plurality of molten tracks on a first surface of the substrate of the metal material using a molten tool to produce a pre-bent substrate; Using the mounting system according to any one of claims 1 to 14 or the pin support system according to any one of claims 15 to 19 as a support structure lying beneath for supporting the pre-bent substrate, and fixing the pre-bent substrate and the mounting system or the pin support system supporting the pre-bent substrate to a jig using a plurality of clamps; Forming the metal workpiece on the second surface of the substrate by a laminated manufacturing process including melting a metal raw material to deposit a layer of molten metal on the second surface of the substrate to form a base material, and depositing subsequent layers of molten metal on the base material to form the metal workpiece, wherein the second surface of the substrate is on the opposite side of the first surface of the substrate. Method.

21. The method according to claim 20, wherein the metal raw material is a metal in the form of powder, wire or a combination thereof.

22. The method according to claim 20 or 21, further comprising preheating the pre-bent substrate to a temperature of about 400 °C to about 900 °C by applying thermal energy to the second side of the substrate before manufacturing the metal workpiece while being fixed to the jig.

23. The method according to any one of claims 20 to 22, wherein pre-bending the substrate includes inducing a thermal gradient in the substrate.

24. The method according to any one of claims 20 to 23, wherein the molten tool includes a heat source selected from a laser beam, an electron beam, a plasma arc, a gas tungsten arc, a gas metal arc and any combination thereof.

25. The method according to any one of claims 20 to 24, wherein during the preliminary bending of the first surface of the substrate, the application area of thermal energy reaches a temperature that is the melting point of the metal material, or a temperature that is about 5 °C to about 50 °C lower or higher than the melting point of the metal material.

26. The method according to any one of claims 20 to 25, wherein during the preliminary bending of the first surface of the substrate, the formation of the molten tracks results in the formation of tensile stress at the center line of each of the molten tracks and the formation of compressive stress in the areas away from the center line of each of the molten tracks when the substrate cools.

27. The method according to claim 26, wherein the tensile stress at the center line of the molten track is within about 10% of the yield strength of the substrate.

28. The method according to claim 26, wherein the tensile stress at the center line of the molten track exceeds the magnitude of the yield strength of the substrate.

29. The method according to any one of claims 20 to 28, wherein the preliminary bending step further comprises directing a cooling gas towards the molten tracks using a gas jet device to promote the cooling of the molten tracks.

30. The method according to claim 29, wherein a thermal gradient is formed in the substrate by directing the cooling gas towards the molten tracks, and residual stress is imparted to the substrate during cooling.

31. The method according to claim 29 or 30, wherein the gas jet device directs the cooling gas towards the molten tracks at a rate of about 50 L / min to about 500 L / min.

32. The method according to any one of claims 29 to 31, wherein the cooling gas is applied in a continuous stream, intermittently, or in a pulsed flow.

33. The method according to any one of claims 29 to 32, wherein the cooling gas comprises an inert gas selected from argon, helium, neon, xenon, krypton, and combinations thereof.

34. The method according to any one of claims 29 to 33, wherein the cooling gas is applied at a temperature of 100 °C or lower.

35. The method according to any one of claims 29 to 34, wherein the cooling gas is applied at a temperature of 25 °C or lower.

36. The method according to any one of claims 29 to 35, wherein the gas jet device generates a turbulent flow of the cooling gas, a laminar flow of the cooling gas, or a combination of a turbulent flow and a laminar flow of the cooling gas.

37. The method according to any one of claims 29 to 36, wherein the gas jet device comprises a plurality of nozzles, the nozzles direct the cooling gas in a direction away from the heat source of the melting tool, and at least one nozzle directs the cooling gas towards the metal of the melted track that remains solidified.

38. The method according to any one of claims 20 to 37, wherein the melted tracks are formed at equal distances from each other.

39. The method according to any one of claims 20 to 38, wherein the distance between the melted tracks is from about 10 mm to about 60 mm.

40. Determining the center line of each wall of the preform formed on the second surface of the substrate; Positioning the melted track on the first surface of the substrate at a distance of about 10 mm to about 20 mm from the center lines of most of the walls of the preform formed on the second surface of the substrate; The method according to any one of claims 20 to 39, further comprising.

41. The method according to any one of claims 20 to 40, further comprising forming most of the melted line at one or more positions other than the one or more positions corresponding to one or more areas occupied by one or more walls of the workpiece formed on the second side of the substrate on the first surface.

42. The method according to any one of claims 20 to 41, wherein the pre-bending forms a pre-bent substrate having uniform elasto-plastic bending.

43. The method according to any one of claims 20 to 42, further comprising pre-bending the substrate while the substrate is clamped to a jig and thermally insulated from the jig.

44. The method according to any one of claims 20 to 43, wherein one or more clamps include an insulating coating on each surface in contact with the pre-bent substrate.

45. The method according to claim 44, wherein the insulating coating comprises a ceramic material, silicon carbide, silicon nitride, boron carbide, or a combination thereof.

46. The ceramic material is alumina, zirconia, titanium oxide, alkaline earth metal silicate, aluminum titanate, zirconium dioxide stabilized by addition of yttrium oxide, yttrium aluminum oxide, ZrV ２ O ７ , Mg ３ (VO ４ ) ２ The method according to claim 45, comprising or a combination thereof.

47. The method according to claim 45 or 46, wherein the thickness of the insulating coating is from 0.1 mm to 5 mm.

48. The method according to any one of claims 44 to 47, wherein the clamp includes a knurling pattern or a waveform on the surface in contact with the pre-bent substrate.

49. The method according to any one of claims 44 to 48, further comprising tightening the clamp to conform the pre-bent substrate to a bending profile defined by the mounting system or the pin support system.

50. The method according to claim 49, wherein each of the clamps is tightened to a torque of about 10 N·m to about 100 N·m.

51. The method according to any one of claims 44 to 50, wherein the clamp is positioned such that the clamp intersects at a starting point or an ending point of the wall of the workpiece being manufactured.

52. The preheating of the pre-bent substrate a) forms a melting track but does not melt the surface of the pre-bent substrate, or b) forms a melting track and melts the surface of the pre-bent substrate with the melting track, The method according to any one of claims 20 to 51, which is performed using one or more melting tools including a DED heat source under the conditions of

53. The method according to claim 51, further comprising positioning the melting tool at a standoff position farther from the standoff position used for forming the workpiece.

54. Further comprising preheating the pre-bent substrate including a first short side and an opposing second short side, and a first long side and an opposing second long side, prior to DED deposition for forming a workpiece, and the preheating a) positioning a melting tool including a DED heat source on the first short side and within a range of about 10 mm to about 60 mm from the first long side of the pre-bent substrate fixed to the jig, b) applying thermal energy from the DED heat source of the melting tool across the surface of the pre-bent substrate starting from the first short side to the second short side on the opposite side across the surface of the substrate to form a first energy application line on the surface, c) displacing and repositioning the DED heat source of the melting tool by a distance of about 10 mm to about 60 mm with respect to the first short side and from the first energy application line towards the second long side, and d) repeating steps b) and c) until the energy application line is applied across the surface of the pre-bent substrate to a position about 10 mm to about 60 mm from the second opposite long side. The method according to claim 53, comprising **Claim 55** The method according to claim 53 or 54, further comprising preheating the preliminarily bent substrate before DED deposition for forming a workpiece by applying thermal energy to the front side of the substrate using a heating device. **Claim 56** The method according to claim 55, wherein the heating device comprises an infrared heater, an induction heater, a resistance heater, or a combination thereof. **Claim 57** The method according to claim 55, wherein the heating device comprises a conductor-in-conduit heat source, a heater strip, a resistive heating strip, an infrared heater, a positive temperature coefficient ceramic heater, a thick film ceramic heater, a resistance wire heater, a resistive ribbon heating device, an infrared heater, and an induction heater or a combination thereof. **Claim 58** The method according to any one of claims 20 to 57, wherein the preheating raises the temperature of the preliminarily bent substrate to a temperature of about 350 °C to about 650 °C. **Claim 59** Forming the metallic workpiece comprises providing a metallic raw material in the form of a wire, using a single melting tool to heat and melt the wire such that the melted metallic material is deposited on the area of the substrate to form a base material, and moving the base material in a predetermined pattern relative to the position of the melting tool such that the continuous deposition of the melted metallic material on the base material solidifies to form a three-dimensional object. The method according to any one of claims 21 to 58, comprising **Claim 60** Forming the metallic workpiece comprises a) providing a metallic raw material in the form of a wire, b) using a first melting tool to heat at least a part of the surface of the substrate to form a preheating area on the substrate, c) using a second melting tool to heat and melt the wire such that the melted metallic material is deposited on the preheating area to form a base material, d) moving the base material relative to the positions of the first melting tool and the second melting tool in a predetermined pattern, e) using the first melting tool to heat at least a part of the surface of the base material to form a preheating area on the base material and depositing the melted metallic material produced by the second melting tool for melting the metallic material on the preheating area on the base material, and f) repeating steps d) and e) such that the continuous deposition of the molten metal material onto the preheating area on the base material solidifies to form a three-dimensional object; The method according to any one of claims 21 to 58, comprising: **Claim 61** using a gas jet device so as to direct a cooling gas across the surface of the molten metal material, or to impinge on the surface of the molten metal material, or to impinge on the surface of the solidified material adjacent to the liquid-solid interface of the molten metal material, or any combination thereof; and moving the base material relative to the positions of the melting tool and the gas jet in a predetermined pattern such that the continuous deposition of the molten metal material solidifies to form a three-dimensional object; The method according to claim 59 or 60, further comprising: **Claim 62** wherein the first melting tool includes a PTA torch, a laser device, an electron beam device, or any combination thereof; wherein the second melting tool includes a PTA torch, a laser device, a coaxial powder feeding nozzle laser system, an electron beam device, or any combination thereof; The method according to claim 59 or 60. **Claim 63** wherein the first melting tool includes a first PTA torch and the second melting tool includes a second PTA torch, or wherein the first melting tool includes a laser device and the second melting tool includes a PTA torch, or wherein the first melting tool includes a PTA torch and the second melting tool includes a laser device, or wherein the first melting tool includes a laser device and the second melting tool includes a coaxial powder feeding nozzle laser system, or wherein the first melting tool includes a PTA torch and the second melting tool includes a torch coaxial powder feeding nozzle laser system, or wherein the first melting tool includes a PTA torch and the second melting tool includes an electron beam device, or wherein the first melting tool includes an electron beam device and the second melting tool includes a PTA torch, or wherein the first melting tool includes an electron beam device and the second melting tool includes a laser device, or wherein the first melting tool includes a laser device and the second melting tool includes an electron beam device; The method according to claim 62. **Claim 64** The method according to claim 63, wherein when the second melting tool includes a PTA torch, the PTA torch is electrically connected to a DC power source such that the electrode of the PTA torch is a cathode and the metal material is a consumable electrode as an anode.

65. The method according to any one of claims 15 to 64, wherein each of pre-bending the substrate, pre-heating the pre-bent substrate, and forming the metal workpiece is performed in a sealed chamber containing an inert atmosphere.

66. The method according to claim 65, wherein the inert atmosphere includes argon, neon, xenon, krypton, helium, or a combination thereof.

67. A system for directed energy deposition, comprising: a jig for fixing a pre-bent substrate; a mounting system according to any one of claims 1 to 14 or a pin support system according to any one of claims 15 to 19, positioned between the jigs and when the pre-bent substrate is fixed to the jigs; a clamp for fixing the pre-bent substrate to the jig; one or more melting tools comprising a DED heat source for melting a metal source into a molten metal deposited on the surface of a base material; a gas jet device for directing a cooling gas to impinge on the solidified material adjacent to the liquid-solid boundary of the liquid melt pool so as to affect the temperature gradient; a supply section of the cooling gas; and an actuator for positioning and moving the base material relative to the melting tool and the gas jet device. A system comprising.

68. The mounting system according to any one of claims 1 to 10, wherein the bending profile is defined by a lattice support structure.

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