Computer-aided design method, computer-aided design system and computer-readable medium for hybrid additive and subtractive manufacturing

Abstract

A method, system, and apparatus for computer-aided design and manufacture of a physical structure using hybrid additive and subtractive manufacturing, including media-encoded computer program products, includes, in one aspect, a method comprising: obtaining data on the 3D geometry of a part; simulating at least a portion of a manufacturing process, said at least a portion including adding a first material in a first stage and removing a second material in a second subsequent stage, wherein the second material comprises a portion of the first material, removing the second material includes mixing between the materials added in the first and second stages, and simulating the thermal effects of adding and removing materials in the first and second stages; and adjusting the amount of said portion based on the simulation results to prevent the part from deviating from its three-dimensional geometry, said deviation resulting in insufficient material available for mixing.

Description

[0001] Cross-reference to related applications

[0002] This application claims the priority benefit of U.S. Patent Application No. 62 / 902,320, filed September 18, 2019, entitled “HYBRID ADDITIVE AND SUBTRACTIVE MANUFACTURING WITH STAINLESS STEEL AND NICKEL ALLOY”.

[0003] Statement regarding sponsorship of research or development

[0004] The project that led to this application has been funded by the EU Horizon 2020 research and innovation program under grant agreement 723538. Background Art

[0005] This specification relates to the computer-aided design and manufacture of physical structures using additive and subtractive manufacturing systems and techniques.

[0006] Computer-aided design (CAD) software and computer-aided manufacturing (CAD) software have been developed, and these are used to generate three-dimensional (3D) representations of parts and, for example, to manufacture the physical structure of those parts using computer numerical control (CNC) manufacturing technology. Furthermore, additive manufacturing, also known as solid freeform manufacturing or 3D printing, refers to any manufacturing process that constructs 3D parts from raw materials (typically powders, liquids, suspensions, or molten solids) in a series of two-dimensional layers or cross-sections. An example of additive manufacturing is fused filament fabrication (FFF). 3D extrusion printers typically use FFF to lay down material (such as plastic filaments or metal wires) unfolded from coils in layers to produce 3D printed parts.

[0007] Additionally, subtractive manufacturing refers to any manufacturing process that produces a 3D part from a material by removing a portion of the material (generally a "blank" or "workpiece" larger than the 3D part). Such manufacturing processes typically involve the use of multiple CNC machine cutting tools in a series of operations, beginning with a roughing operation, optionally a semi-finishing operation, and a finishing operation. During the roughing operation, the cutting tools using a CNC machining system rapidly (relative to the semi-finishing and finishing operations) remove a large portion of the workpiece to approximate the final shape of the manufactured part. Furthermore, hybrid manufacturing systems combining additive and subtractive manufacturing have been developed, such as CNC machines that combine laser metal deposition with high-precision 5-axis adaptive milling. Summary of the Invention

[0008] This specification describes techniques related to the computer-aided design and manufacture of physical structures using hybrid additive and subtractive manufacturing systems and technologies.

[0009] Generally, one or more aspects of the subject matter described in this specification can be embodied in one or more methods, including: Obtaining data on the three-dimensional geometry of a part to be manufactured from materials using a hybrid additive and subtractive manufacturing system comprising a series of two or more stages, each of the two or more stages including adding material with additive manufacturing tools and removing material with subtractive manufacturing tools; simulating at least a portion of the manufacturing process based on the data and the physical properties of the materials, the at least a portion including adding a first material using additive manufacturing tools in a first stage of the two or more stages, and removing a second material using subtractive manufacturing tools in a second stage of the two or more stages, wherein the first stage precedes the second stage, wherein the second material comprises a portion of the first material, wherein removing the second material comprises mixing between the materials added in the first stage and the second stage, and wherein the simulation includes simulating the thermal effects of adding and removing materials in the first stage and the second stage; adjusting the amount of the portion of the first material included in the second material based on the results of the simulation according to the physical properties of the materials to prevent the part from deviating from its three-dimensional geometry during a portion of the manufacturing process, the deviation resulting in insufficient material available for mixing; and providing the adjusted amount for manufacturing the part using the hybrid additive and subtractive manufacturing system.

[0010] The manufacturing process may include adding a third material using additive manufacturing tools in a second stage of the two or more stages, and removing a fourth material using subtractive manufacturing tools in a first stage of the two or more stages, wherein the first material comprises the fourth material, the second material comprises a portion of the third material, the simulation includes simulating vibrations experienced at least during the removal of the second material, and the method includes modifying two or more layers and thus the two or more stages in response to excessive vibration. Simulating vibration may include simulating instabilities during cutting based on predicted cutting forces and dynamic responses.

[0011] Adjusting the amount of the first material included in the second material may include increasing the amount of over-build of the first material to be added using additive manufacturing tools in the first stage of the two or more stages, relative to the three-dimensional geometry of the part.

[0012] The manufacturing process may include using additive manufacturing tools to add a third material in a second stage of the two or more stages, and using subtractive manufacturing tools to remove a fourth material in a first stage of the two or more stages, wherein the first material includes the fourth material, the second material includes a portion of the third material, and adjusting the amount of the portion of the first material included in the second material includes reducing the amount of the fourth material and increasing the portion of the first material included in the second material.

[0013] The component may be a turbine rotor, which includes a hub and blades designed to operate in a high-temperature environment, and the simulation may include simulating the machining of blades constructed using additive manufacturing tools on top of the blade root, which is an integral part of the hub, in two or more phases.

[0014] The method may include manufacturing parts using a hybrid additive and subtractive manufacturing system. The hybrid additive and subtractive manufacturing system may include one or more computer processing devices, the one or more computer processing devices including at least one non-transitory computer-readable medium encoded with a computer-aided design program operable to perform acquisition, simulation, adaptation, provisioning, and manufacturing.

[0015] The described method may use a non-transitory computer-readable medium encoding instructions operable to cause a data processing device to perform the operation of the method. Alternatively, a system implementation may include a data processing device (including at least one hardware processor) and a non-transitory computer-readable medium encoding instructions for a computer-aided design program that implements the method. Finally, the system implementation may include a hybrid additive and subtractive manufacturing system, and the instructions of the computer-aided design program may be configured to cause the data processing device to manufacture a part using the hybrid additive and subtractive manufacturing system.

[0016] Specific implementations of the subject matter described in this specification can be carried out to achieve one or more of the following advantages. Building structures in a series of layers during the corresponding additive and subtractive manufacturing stages allows for the use of shorter and / or more conventional tools, which reduces the manufacturing cost of complex structures. Feedback from numerical simulations of the combination of additive and subtractive manufacturing can be used to modify the manufacturing plan to improve the manufacturing process and / or improve the quality of the manufactured structures.

[0017] The number of manufacturing stages and / or the overlap between additive and subtractive manufacturing within and between stages can be modified to prevent undesirable instabilities and deformations during additive deposition, ensure uniform material removal during machining, and / or provide stability relative to vibration and machining dynamics during subtractive machining. The systems and techniques described in this document can be used to avoid excessive vibrations during subtractive manufacturing (which could damage the workpiece and / or tool), for example, by informing the excessive vibrations through cutting forces and dynamic prediction models used in numerical simulations, thus avoiding part inaccuracies, tool damage / breakage, and the potential for complete workpiece scrapping.

[0018] The number of hybrid manufacturing stages (and / or the distance covered by the hybrid manufacturing stages) and the amount of additive and subtractive manufacturing to be performed in each stage can be modified based on the part being constructed, the length and strength of the available tools, numerical simulations of the manufacturing process (e.g., the length and strength of the cutting tools and therefore the expected amount of vibration during subtractive manufacturing), and the expectation of minimizing manufacturing interruptions caused by the transition between additive and subtractive manufacturing. Using the hybrid staged manufacturing system and technology described in this document can result in a reduction in the material used to build the part and a reduction in the machine time required to manufacture the part. These and other advantages can be achieved in a single-setup hybrid production process.

[0019] Furthermore, the phased hybrid approach facilitates the use of more conventional (rigid and off-the-shelf) tools rather than specialized (long, thin, and expensive) ones. This means that resources that would otherwise be spent on designing and procuring specialized tools can be spent on manufacturing itself, thereby increasing productivity. In addition, the use of the simulation-supported digital workflows described in this document reduces the need for specialized knowledge and guesswork in complex manufacturing projects.

[0020] Details of one or more embodiments of the subject matter described herein are set forth in the accompanying drawings and the following description. Other features, aspects, and advantages of the invention will become apparent from the description, drawings, and claims. Attached Figure Description

[0021] Figure 1 An example of a system that can be used to design and manufacture physical structures using hybrid additive and subtractive manufacturing is shown.

[0022] Figure 2A and Figure 2B An example of a construction sequence for a blade manufactured using a hybrid additive and subtractive manufacturing process is shown.

[0023] Figure 2C An example of over-building during the additive manufacturing process in hybrid additive and subtractive manufacturing is shown.

[0024] Figure 3A An example of a process for altering a manufacturing plan based on numerical simulations of hybrid additive and subtractive manufacturing of a structure is shown.

[0025] Figures 3B to 3E It shows that it can be used Figure 3A Detailed examples of implementation during the hybrid additive and subtractive manufacturing process.

[0026] Figure 4 It is a schematic diagram of a data processing system that can be used to implement the described system and technology.

[0027] The same reference numerals and labels in the various figures indicate the same elements. Detailed Implementation

[0028] Figure 1 An example of a system 100 for designing and manufacturing physical structures using hybrid additive and subtractive manufacturing is shown. Computer 110 includes a processor 112 and memory 114, and computer 110 is connectable to a network 140, which may be a private network, a public network, a virtual private network, etc. Processor 112 may be one or more hardware processors, each of which may include multiple processor cores. Memory 114 may include both volatile and non-volatile memory, such as random access memory (RAM) and flash RAM. Computer 110 may include various types of computer storage media and devices that may include memory 114 to store instructions for a program running on processor 112.

[0029] Such programs include one or more three-dimensional (3D) modeling, simulation (finite element analysis or other) and / or manufacturing control programs, such as computer-aided design (CAD) program 116, which simulates a combination of additive and subtractive manufacturing and adjusts the manufacturing schedule (during 3D modeling of the structure / object and / or during the generation of toolpath specifications from the 3D model) to improve the hybrid additive and subtractive manufacturing of the structure / object. As used herein, “CAD” refers to any suitable program used to design a manufacturing schedule for a physical structure, regardless of whether the program is able to interface with and / or control the manufacturing equipment to construct the physical structure, and regardless of whether the program can be used to design a physical structure that meets design requirements. Therefore, CAD program 116 may include computer-aided engineering (CAE) programs, computer-aided manufacturing (CAM) programs, architectural, engineering and construction (AEC) programs, etc.

[0030] CAD program 116 may run locally on computer 110, remotely on one or more remote computer systems 150 (e.g., one or more server systems of one or more third-party providers accessible from computer 110 via network 140), or both locally and remotely. Therefore, CAD program 116 may be two or more programs operating collaboratively on two or more separate computer processors, wherein one or more programs 116 operating locally on computer 110 can “offload” processing operations (e.g., numerical simulation operations) to the cloud by causing one or more programs 116 on one or more computers 150 to perform offloading processing operations.

[0031] The CAD program 116 presents a user interface (UI) 122 on the display device 120 of the computer 110, which can be operated using one or more input devices 118 of the computer 110 (e.g., keyboard and mouse). It should be noted that although in Figure 1 While shown as separate devices, display device 120 and / or input device 118 may also be integrated with each other and / or with computer 110, such as in a tablet computer or a virtual reality (VR) or augmented reality (AR) system. For example, input / output devices 118, 120 may include VR input gloves 118a and VR headset 120a.

[0032] User 190 can interact with CAD program 116 to create and / or load a 3D model 132 of a part to be manufactured using a hybrid additive and subtractive manufacturing system (e.g., in and / or from document 130), which may include one or more computer numerical control (CNC) manufacturing machines 170. This can be done using known graphical user interface tools, and various known 3D modeling formats can be used on a computer to define the 3D model 132, such as using solid models (e.g., voxels) or surface models (e.g., B-Rep (boundary representation) and surface meshes). Additionally, in some embodiments, user 190 can interact with program 116 to modify the 3D model 132 of the part as needed.

[0033] In the example shown, Model 132 is a 3D model of a specific turbine impeller, but many different types of models can be used with the systems and techniques described in this document. Generally, the systems and techniques described are more suitable for manufacturing components comprising tall structures with limited space between them, such as blades (or rotor blades) of bladed disks or turbine impellers for aerospace or power generation applications, where the heights of the blades are compared, and they are often adjacent to each other. The hybrid manufacturing described in this document involves building such structures in a series of layers in corresponding manufacturing stages, where each stage includes both material deposition and material removal. This means that shorter tools can be used when manufacturing blades adjacent to each other, as only the height of the current layer needs to be covered, rather than the entire blade height. However, despite this specific applicability to manufacturing tall structures with limited space between them, the systems and techniques described are also more generally applicable to various types of structures to be designed and manufactured using CAD programs and hybrid additive and subtractive manufacturing.

[0034] In some embodiments, the hybrid additive and subtractive manufacturing system is a single CNC machine 170, which includes subtractive manufacturing (SM) tools 172 and additive manufacturing (AM) tools 176, the tools being removable and / or having removable toolheads. It will be understood that many different types of cutting tools 172 are available in the CNC machine 170, including end mills with various ball ends, tapers, tip radii, and cylindrical shapes. These different cutting tools 172 may include integral tools (e.g., integral carbide round tools) with different diameters and tip radii that produce different cutting surface geometries of the tool 172 and / or inlaid tools with different diameters and metal (e.g., carbide) inserts that produce different cutting surface shapes of the tool 172. These different tools 172 may be arranged according to tool families, wherein the tool families have one or more shared tool characteristics (e.g., a series 172A of integral carbide round tools has different diameters and tip radii that produce different cutting surface geometries, and a series 172B of inlaid tools has different diameters and metal inserts that produce different cutting surface geometries). Additionally, the CNC machine 170 may include other components and systems, such as a rotatable platform / attachment (e.g., for a five-axis milling process) and a cleaning and cooling system (e.g., a water spray cleaning and cooling system).

[0035] Furthermore, various types of AM tools 176 may be available in the CNC machine 170. For example, the CNC machine 170 may include one or more AM tools 176 employing particle additive manufacturing technologies such as selective laser sintering (SLS) or direct metal laser sintering (DMLS). As another example, the CNC machine 170 may include one or more AM tools 176 employing extrusion technologies such as fused filament fabrication (FFF). Other AM systems and technologies are also available, such as using directional energy deposition (DED) as a metal additive process, where the power source may be an electric arc, a laser, or an electron beam. Additionally, the AM tools 176 may be designed to use powder or wire feed.

[0036] In some implementations, the hybrid additive and subtractive manufacturing system comprises two or more CNC machines that may be identical or different from each other. In some cases, the SM tool 172 and AM tool 176 are kept in separate CNC machines, rather than combined in a single machine. Thus, machine 170 may be a CNC SM machine with cutting tool 172 but excluding AM tool 176. However, regardless of whether CNC machine 170 includes AM tool 176, the SM tool 172 of CNC machine 170 provides multi-axis and multi-tool milling capabilities.

[0037] A standalone CNC AM machine 174 may include AM tools 176. For example, AM machine 174 may include a laser 174A (e.g., a CO2 laser) and a scanner 174B (e.g., a galvanometer or rotating polygonal mirror) to construct a semi-finished structure in a powder bed 174C using powder delivery and a piston mechanism (not shown). Alternatively, laser 174A may be attached to a 2.5-axis, 3-axis, or more-axis motion control device to perform laser cladding at a designated location using powder or wire feed. It will be understood that embodiments using standalone CNC machines for both SM and AM tools may require additional steps or devices to transfer workpieces from one machine to another, such as part-handling robots that move workpieces between standalone CNC machines 170, 174. Alternatively, such embodiments may utilize a shared workpiece platform accessed by standalone CNC machines 170, 174.

[0038] Therefore, regardless of whether the hybrid additive and subtractive manufacturing system is a single AM+SM machine 170 or separate AM and SM machines 174, 170, a single-setup hybrid production process can be employed. That is, the workpiece can be fixed to a work tray (or clamped to another object, or otherwise held in place) in one go, and then a sequence of manufacturing stages (each of the SM and AM operations) can be performed on the workpiece to form the desired part without having to release the workpiece during the manufacturing stage sequence. For example, a single AM+SM machine 170 may include a clamping tray system and clamping system provided by Erowa AG (or another company) in Büron, Switzerland, within a hybrid machine provided by Hamuel Maschinenbau GmbH & Co. KG (or another company) in Meide, Germany, which includes in-process measuring devices. For further details on hybrid additive and subtractive manufacturing systems, see U.S. Patent Nos. US20160221122A1, US20170129180A1, and US20portion 200086424A1, which are incorporated herein by reference. Despite these potential variations in the manufacturing systems to be used, the systems and techniques described in this document, implemented by CAD program 116, remain applicable to these variations in the number (and capacity) of machines to be used for hybrid AM+SM manufacturing.

[0039] As described above, CAD program 116 simulates a combination of additive and subtractive manufacturing and adjusts the manufacturing schedule to improve the hybrid additive and subtractive manufacturing of structures / objects. Specifically, numerical simulations of one or more physical properties of one or more materials used to construct the structure during the additive and subtractive manufacturing processes can be performed to provide feedback for adjusting the blending and matching of additive and subtractive manufacturing operations. It should be noted that the adjustments made may include modifying the 3D model of the structure / object and / or modifying the toolpath specifications generated from the 3D model of the structure / object (for AM, SM, or both).

[0040] In the example shown, 3D model 132 is a 3D model of bladed disk 180, the physical object to be constructed using a hybrid additive and subtractive manufacturing system. Bladed disk 180 comprises multiple blades, with their heights relative to each other, placed close together. For example, the blades may be 120 mm long and spaced approximately 9 mm apart at their tips and approximately 2 mm apart where they connect to the hub of bladed disk 180. Therefore, milling bladed disk 180 from an additively manufactured workpiece may require specialized cutting tools that are long and thin enough to reach all the gaps in the design of bladed disk 180.

[0041] However, longer and thinner cutting tools generally generate more vibration, which can destabilize the machining process, potentially create scratches that require more finishing operations to remove, and may lead to more tool breakage. One solution to this problem is to construct the cutting tool from a stronger, more specialized material that vibrates less, but this increases costs. It should be noted that the longer and thinner the machine tool, the more vibration it tends to introduce, leading to a higher likelihood of tool breakage and damage to the manufactured parts, or slower manufacturing when machine tools are used more carefully to avoid tool breakage and damaged parts.

[0042] Another solution is to construct the blades of the bladed disk 180 in a series of layers during the corresponding manufacturing stages, where each stage includes both depositing material using an AM tool 176 and removing material using an SM tool 172. This allows for the use of shorter and / or more conventional tools in the manufacturing process, which reduces costs. Furthermore, the systems and techniques described in this document can prevent instability and undesirable deformation during the AM and / or SM processes when constructing the part.

[0043] Figure 2A An example of a build sequence for a blade manufactured in a series of three layers using hybrid additive and subtractive manufacturing is shown. Hub portion 200 represents a part of the structure on which the blade will be manufactured. Hub portion 200 may be a part previously manufactured, for example by casting or forging (hot or cold) and / or by conventional SM roughing operations performed on a block of starting material, or hub portion 200 may be manufactured using one or more AM tools and one or more SM tools included in the hybrid additive and subtractive manufacturing system. In any case, the first layer 210 of the blade is built using a deposition process 204 with one or more AM tools in the hybrid additive and subtractive manufacturing system (e.g., using a laser head and measurement system 176 with a 1 kW fiber laser source, which uses molten metal powder from a powder supply system to build the first layer 210).

[0044] Then, machining process 212 is performed using one or more SM tools from a hybrid additive and subtractive manufacturing system (e.g., high-precision and dynamic 5-axis machining performed concurrently with adaptive milling). It should be noted that machining process 212 covers a portion of the hub portion 200 and a portion of the first layer 210 of the manufactured blade, resulting in a partially machined hub portion 200A (or, in the case of prior machining, a fully machined hub portion 200A) and a partially machined first layer 210A of the blade. Therefore, machining process 212 incorporates the first layer 210 into the hub portion 200 to a minimum.

[0045] However, in some embodiments, machining process 212 covers more (or all) of the hub portion 200. Even so, machining process 212 should only cover a portion of the first layer 210, leaving an unfinished portion of the first layer 210 on which the next layer is to be built. Machining process 212 may include both semi-finishing and finishing operations. In some embodiments, machining process 212 includes semi-finishing the entire first layer 210 of the blade and at least a portion of the hub portion 200, followed by finishing the at least a portion of the hub portion 200 and only a portion of the first layer 210, thus leaving an unfinished portion of the first layer 210 on which the next layer is to be built. In some embodiments, machining process 212 includes semi-finishing a first portion of the first layer 210 of the blade and at least a portion of the hub portion 200, followed by finishing a second portion of the hub portion 200 and only a second portion of the first layer 210, wherein the second portion is smaller than the first portion, thus leaving an unfinished (rough) portion above the first portion of the first layer 210 on which the next layer is to be constructed, and also leaving an unfinished portion of the first layer 210 above the second portion to facilitate subsequent machining operations, including mixing between different layers of the blade.

[0046] A second layer 220 of the blade is constructed on top of a partially machined first layer 210A using a deposition process 214 employing one or more AM tools in a hybrid additive and subtractive manufacturing system. A machining process 222 is then performed using one or more SM tools in the hybrid additive and subtractive manufacturing system. The machining process 222 incorporates the second layer 220 into the partially machined first layer 210A to a minimum, and thus completes the fabrication of the first layer of the blade, resulting in a fully machined first layer 210B.

[0047] However, machining process 222 only covers a portion of the second layer 220 of the manufactured blade, thereby producing a partially machined second layer 220A of the blade, leaving an unfinished portion of the second layer 220 on which the next layer is to be built. Similar to machining process 212, machining process 222 may include both semi-finishing and finishing operations. In some embodiments, machining process 222 includes semi-finishing a portion of the fully and partially machined first layer 210A of the second layer 220, followed by finishing the portion of the partially machined first layer 210A and only a portion of the second layer 220, thus leaving an unfinished portion of the second layer 220 on which the next layer is to be built. In some embodiments, machining process 222 includes semi-finishing a first portion of the second layer 220 and a portion of the partially machined first layer 210A, followed by finishing the portion of the partially machined first layer 210A and only the second portion of the second layer 220, wherein the second portion is smaller than the first portion, thus leaving an unfinished (rough) portion above the first portion of the second layer 220 on which the next layer is to be constructed, and also leaving an unfinished portion of the second layer 220 above the second portion to facilitate subsequent machining operations, including mixing between the second layer 220 and the partially machined first layer 210A.

[0048] A third layer 230 of the blade is constructed on top of a partially machined second layer 220A using a deposition process 224 employing one or more AM tools in a hybrid additive and subtractive manufacturing system. A machining process 232 is then performed using one or more SM tools in the hybrid additive and subtractive manufacturing system. The machining process 232 incorporates the third layer 230 into the partially machined second layer 220A to a minimum, and thus completes the fabrication of the second layer of the blade, resulting in a fully machined second layer.

[0049] In some cases, machining process 232 only covers a portion of the third layer 230 of the manufactured blade, such as... Figure 2A As shown, this results in a partially machined third layer of the blade, for example, leaving an unfinished portion of the third layer 230 on which the next layer will be built. However, if the third layer 230 is the final layer of the blade, the machining process 232 can cover the entire third layer 230 of the blade, as shown. Figure 2B As shown in the diagram. And like machining process 222, machining process 232 may include both semi-finishing operations and finishing operations.

[0050] Figure 2B It shows Figure 2AThe following is an example of a fully manufactured blade, illustrating a construction sequence. A fully machined first layer 210B is constructed on top of hub portion 210A using three separate manufacturing processes spanning two distinct manufacturing stages. In the first manufacturing stage, the first layer of the blade is constructed via deposition process 204 (additively), and then a portion of the first layer is constructed via machining process 212 (subtractively). It should be noted that when using a hybrid staged manufacturing process, the AM and SM tools only need to be adapted to the height of the first layer of the blade, not the entire height of the blade.

[0051] Then, in the second manufacturing stage, the first layer 210B of the blade is fully machined by machining process 222 (subtractive manufacturing) to construct the first layer of the blade. In other words, the first layer of the blade is completed using three separate processes 204, 212, and 222, which are performed in two different manufacturing stages (the first manufacturing stage manufactures the first layer, and the second manufacturing stage manufactures the second layer). Similarly, a fully machined second layer 220B is constructed on top of the fully machined first layer 210B using three separate manufacturing processes that span two different manufacturing stages but overlap with the first layer. Therefore, the second layer of the blade is completed using three separate processes 214, 222, and 232, which are performed in two different manufacturing stages (the first manufacturing stage manufactures the second layer, and the second manufacturing stage manufactures the third layer).

[0052] However, the final layer of the blade requires only two separate processes in a single manufacturing stage: deposition process 224 and machining process 232 are performed in the third layer manufacturing stage to complete the third layer 230A of the blade. Other processes may also be included in the respective manufacturing stages. Furthermore, note that the corresponding first, second, and third manufacturing stages may include constructing the first, second, and third layers of multiple other blades attached to the same hub. Additionally, the number of manufacturing stages does not need to be three, and in some embodiments, the CAD program 116 determines how many layers are desired, as described below. Figure 3A A more detailed description follows. But regardless of the total number of layers and therefore the number of manufacturing stages, there will be one or more overlaps 250, 255 between the individual manufacturing stages that construct the part.

[0053] The overlaps 250 and 255 are caused by the misalignment between the individual layers of the blades constructed through machining processes 212, 222, and 232 and deposition processes 204, 214, and 224. Figure 2BAs shown in the diagram. Therefore, overlap 250 is the difference between the end point of deposition process 204 and the end point of machining process 212 (or the start point of machining process 222). Similarly, overlap 255 is the difference between the end point of deposition process 214 and the end point of machining process 222 (or the start point of machining process 232). However, the sizes of overlaps 250 and 255 can be varied depending on the specific part to be manufactured in order to improve the hybrid manufacturing of the part.

[0054] For example, numerical simulations of machining processes 222 and 232 may include simulating the thermal effects of the AM operation relative to the SM operation, which would require sufficient material to mix between the partially machined first layer 210A and the deposited second layer 220, and between the partially machined second layer 220A and the deposited third layer 230, respectively. Due to the use of a layered manufacturing process, some thermal effects at the interface between the two layers (and potentially at the overall part level) could cause the part to move or deform during manufacturing. To address this, a sufficient amount of the deposited first layer 210 should be left in the partially machined first layer 210A (during machining process 212) to absorb heat, and any (or excessive) movement or deformation should be prevented during the addition of the second layer 220 (214), thus avoiding insufficient material in the proper places to successfully complete machining process 222, including mixing between the first and second layers. Similarly, a sufficient amount of deposited second layer 220 should be left in the partially machined second layer 220A (during the machining process 222) to absorb heat and to prevent any (or excessive) movement or deformation during the addition of the third layer 230 224, thereby avoiding insufficient material in the proper place to successfully complete the machining process 232, including mixing between the second and third layers.

[0055] Therefore, numerical simulations of deposition processes 214, 224 and / or machining processes 222, 232 reveal the need to adjust one or both of the overlaps 250, 255 (potentially increasing or decreasing dimensions by different amounts in different regions of the part) to facilitate the blending performed during machining processes 222, 232. Additionally, numerical simulations of processes 214, 222, 224, 232 reveal the need to adjust the overbuild amount (potentially increasing or decreasing dimensions by different amounts in different regions of the part), as described below. Figure 2C and Figure 3ATo describe in more detail, it will be understood that the results of numerical simulations will depend on the physical properties of the materials used to manufacture the parts. When new molten material is added to different materials (including different metal alloys, such as stainless steel and nickel alloys) and when the deposited material is machined using a given type of cutting tool, these different materials will have different strengths and stability. Therefore, it will be necessary to leave more or less material on the part in one of the stages of the process to ensure stability and to avoid deviations during the mixed-stage manufacturing process.

[0056] Additional numerical simulations can be performed, and further modifications to the hybrid manufacturing process can be made based on feedback from said simulations. Nevertheless, the amount of material deposited in a layer by AM during an earlier manufacturing stage is adjusted based on the results of numerical simulations, and this portion is then removed during a subsequent manufacturing stage by SM, primarily performed on another (higher) layer. The adjusted “amount” can include the size of the overlap between the subsequent and preceding manufacturing stages (e.g., the size of one or both of overlaps 250, 255), the extent of material deposited at least in the overlap region between the subsequent and preceding manufacturing stages (beyond the envelope of the part’s 3D geometry, i.e., overbuild amount) (e.g., the amount of material deposited 204, 214 extends beyond the outer surface of the blade at least in the region of one or both of overlaps 250, 255), or both the size of the overlap and the extent of the deposited material. It should also be noted that the extent of material deposited in a given layer (overbuild amount) is important for providing sufficient support for depositing higher layers on top.

[0057] Figure 2C An example of over-building during the additive manufacturing process in hybrid additive and subtractive manufacturing is shown. It will be understood that the manufactured additive portion will require the deposition of sufficient material to fill the entire 3D space that the final part will occupy, plus an additional amount beyond this 3D space to provide material that will be machined away by the hybrid manufacturing SM process. The advantage of hybrid manufacturing is that only a small amount of additional material (relative to the material required to form the part) will need to be deposited, thus saving material during the manufacturing process.

[0058] The small amount of additional material required can be limited by generating an enlarged version of the part geometry used for AM construction. This can be done by generating an enlarged version of the 3D model of the part geometry (e.g., an outward offset of the part's B-Rep) to form a 3D model of the structure to be built by the AM process (e.g., the AM version of the B-Rep of the part prior to SM processing), and / or modifying the toolpath specifications created for the AM process based on the 3D model of the part geometry. In any case, the enlarged version of the 3D model of the part geometry may not be large enough to support higher layers and provide sufficient material in the correct locations for the SM process (e.g., after any deformation movement caused by AM construction of higher layers). It should be noted that this is the case when depositing material on top of a lower object, regardless of whether the AM process allows for a small amount of overhang.

[0059] Figure 2C An example is shown in which the first layer 250 includes a finished (or semi-finished) portion 252, a transition zone 254, and a transitional build-up portion 256 prepared for the next layer. It should be noted that, for clarity in this disclosure, [the following is omitted as it is not part of the original text]. Figure 2C The sizes of these different regions of the part are magnified, but even so, the over-build portion of each layer will often taper outwards, as shown in the figure. In any case, the over-build portion 256 of the first layer 250 needs to be large enough to support AM deposition of material 260 in the next AM build in the next stage. And the AM deposition of material 260 needs to be large enough that the SM process in the next stage can remove material to form the second layer 265.

[0060] Additionally, the AM deposition of the material forming the first layer 250 needs to be large enough that, after any movement or deformation caused by the AM deposition of material 260 on top of the first layer 250, there remains sufficient material in the correct location within the first layer 250 to allow the SM process to cut the correct final geometry of the part. Therefore, the manufacturing plan can be formulated by performing the numerical simulations described in this document to define the finishing (or semi-finishing) portions, transition zones (corresponding to overlaps), and over-built portions of each of the multiple layers 250, 265, 270, 275, 280, 285. It should be noted that in Figure 2C In the diagram, solid lines represent finished (or semi-finished) portions of a layer, dashed lines represent transition zones, and dotted lines represent over-built portions. The manufacturing plan defines these different portions of the part to be built during the hybrid manufacturing process by generating one or more 3D models and / or one or more toolpath specifications (e.g., for AM and SM processes) for different layers of the part, with appropriate over-built and / or overlap (note that overlap can be a combination of transition zones and the amount of over-built left).

[0061] Return again Figure 1 The CAD program 116 can perform the operations described herein to develop a manufacturing plan for the 3D model 132 of the part. This may include preparing the 3D model 132 of the physical structure for manufacturing the part by generating toolpaths for use by a hybrid additive and subtractive manufacturing system. For example, the 3D model 132 can be used to generate a toolpath specification document 160, which can be sent to a single AM+SM machine 170 and used to control the operation of one or more AM tools 176 and one or more SM tools 172, as described herein.

[0062] This can be done after a request from user 190 or in response to a request from the user for another action, such as sending 3D model 132 to a hybrid additive and subtractive manufacturing system that can be directly connected to computer 110 or connected to said computer via network 140, as shown. This can involve a post-process performed on local computer 110 or a cloud service to export 3D model 132 to an electronic document on which manufacturing is based. It should be noted that an electronic document (which will be simply referred to as a document for the sake of simplicity) can be a file, but does not necessarily correspond to a file. A document can be stored in a portion of a file that stores other documents, in a single file dedicated to the document in question, or in multiple collaborative files.

[0063] Furthermore, in some embodiments, computer 110 is integrated into CNC machine 170, and therefore document 160 is created using the same computer that manufactures part 180 using document 160. Thus, in some embodiments, the hybrid additive and subtractive manufacturing system includes computer 110 and is capable of executing the techniques described herein to optimize part manufacturing strategies, and performing final inspection of the part together in one system (using suitable measuring devices, including in-process measuring devices), and possibly together in a single machine 170. Toolpath specification document 160 (e.g., a suitably formatted numerical control (NC) program) includes one or more toolpath specifications that cause CNC machine 170 to perform a hybrid manufacturing process using AM tool 176 and SM tool 172 to manufacture physical object 180 (corresponding to 3D model 132).

[0064] Figure 3AAn example of a process for altering a manufacturing plan based on numerical simulation of hybrid additive and subtractive manufacturing based on a structure is illustrated. For example, data on the three-dimensional geometry of 300 parts to be manufactured is obtained by CAD program 116. These parts are to be manufactured from materials using a hybrid additive and subtractive manufacturing system comprising additive and subtractive manufacturing tools, as described in the literature. Furthermore, the data may include: a 3D model (e.g., B-Rep) of the part (or a portion thereof); one or more toolpath specifications for AM tools and / or SM tools, which have been generated from the 3D model of the part, for example, based on input regarding cutting conditions / parameters; or both 3D model and toolpath specification data.

[0065] The part may be an airfoil, bladed disk, turbine rotor / impeller, or a portion thereof (e.g., one or more blades or impellers to be constructed on a hub). The material may be stainless steel, nickel, titanium, aluminum, or one or more alloys thereof. Additive manufacturing tools may be laser deposition tools or arc tools, which may be used with powder or wire feed. Subtractive manufacturing tools may be 2.5-axis, 3-axis, or 5-axis or more cutting tools. It will be understood that other parts (or portions thereof), materials, and tools may also be used with the systems and techniques described in this document, wherein a combination of additive and subtractive manufacturing is used to construct 3D parts from raw materials (generally powder, liquid, suspension, or molten solid).

[0066] In any case, a hybrid additive and subtractive manufacturing system manufactures a part using a manufacturing process consisting of a series of two or more stages, each of which includes adding material with additive manufacturing (AM) tools and removing some of the material with subtractive manufacturing (SM) tools to build the next layer of the part. In some implementations, the number of layers (and therefore the number of stages for manufacturing the part) is set to a default initial number, such as a default of two or three layers / stages. In some implementations, the number of layers is predetermined by the user or another process. For example, the initial number of layers may be specified by data, such as data that may include toolpath specifications for AM and SM tools that have already divided part manufacturing into a predetermined number of layers and therefore stages of part manufacturing.

[0067] In some implementations, the number of layers can be modified to balance productivity and quality in the manufacturing process. It should be noted that fewer layers are preferred because more layers mean more tool changes. More changes between using AM tools and SM tools mean more interruptions in the manufacturing process, which generally reduces productivity. However, depending on the part to be manufactured and the available SM tools, too few layers can lead to undesirable vibrations during machining by the SM tools, which may reduce the quality of the manufactured parts.

[0068] Generally, the number of layers to be used will depend on the strength of the material, the 3D geometry of the part (e.g., the shape and size of different parts of the part relative to each other, such as the aspect ratio of blades and the spacing between blades), and the cutting conditions / parameters used in the manufacturing process. These cutting conditions / parameters may include information about one or more different cutting tools and / or cutting data for one or more different cutting tools that can be used as SM tools in the hybrid manufacturing process. The information on the cutting conditions / parameters may include details of the SM tool to be used (tool size, shape, and number of grooves, if any), depth of cut, feed rate, spindle speed, infeed rate, step size, and step drop, plus workpiece material (e.g., nickel, titanium, aluminum, or one or more alloys thereof) and tool material (e.g., cemented carbide) specifications. In some embodiments, some or all of these cutting conditions / parameters are obtained from another source (e.g., a provider of the hybrid manufacturing system).

[0069] The additive manufacturing of the current layer of part 310 begins at the lowest layer, i.e., at the first stage, for example, by CAD program 116 simulating the current layer of part 310 based on data and the physical properties of the materials. This may involve using finite element analysis (or other numerical simulation techniques) to simulate the thermal effects of adding material in the current stage. Numerical simulation 310 may involve simulating the thermal effects at the interface between the current layer and the object built on it by the AM tool (e.g., from a previous layer in the previous stage), the thermal effects at the overall part level, or both (e.g., simulating the thermal effects at the overall part level and the thermal effects at the interface between the deposited materials added in the first and second stages of manufacturing).

[0070] Figure 3B A visual representation of the numerical simulation is shown, which enables the execution of a streamlined AM workflow and the development of a manufacturing plan to successfully manufacture a 3D printed part from a 3D model of the part on the first attempt. Figure 3B The example shows simulations of inactive element 311A, evolving interface 311B, and active element 311C, as well as a simulation of shift 312. Return to Figure 3AThe thermal effects of simulation 310 can include the movement or deformation of the part being manufactured due to the use of AM tools. Generally, any suitable information (e.g., test data) that affects how the part will move or deform (during the deposition of material to form the current layer of the part) can be used to generate a thermal and force model of the workpiece in the numerical simulation 310 of the AM tool, which is then cut using the SM tool.

[0071] For example, CAD program 116 simulates subtractive manufacturing of the current layer of part 315 based on data and the physical properties of the material. This may involve using finite element (FE) analysis (or other numerical simulation techniques) to simulate the vibration and / or thermal effects of material removal in the current stage, where material removal includes mixing between the current layer and an object below the current layer (e.g., a previous layer from a previous stage). Numerical simulation 315 may involve simulating thermal effects at the interface between the current layer and the object below the current layer, simulating thermal effects at the overall part level, or both. It should be noted that material may be removed from the top interface (and from the side) of a previous layer from a previous stage (or other objects below the current layer).

[0072] Numerical simulation 315 may involve simulating the vibrations experienced by an SM tool during material removal from both the current layer and an object below it, the removal comprising a mixture between the current layer and the object below it. The vibrations simulated 315 may be consistent with cutting conditions / parameters and may include evaluating the skew experienced by the SM tool and the workpiece as material is cut from the workpiece by the SM tool. Generally, any suitable information (e.g., test data) affecting how the tool and / or workpiece will move during cutting can be used to generate a force model of the forces exerted by the SM tool on the workpiece for use in simulation 315. It should be noted that the shorter and stronger the SM tool, the less vibration will be present in the tool during subtractive manufacturing (shorter tools are inherently stiffer).

[0073] For example, CAD program 116 performs a check 320 to see if more layers of manufacturing still need to be simulated. If so, the process moves 325 to the next (higher) layer to simulate the construction of that next layer by 310, 315 AM tools, and SM tools. In the example shown, all stages of manufacturing are simulated before any changes are made to the manufacturing schedule. However, it will be understood that this is not necessary. In some implementations, only one or both of two or more stages are simulated before the results of the simulation are evaluated to determine whether changes to the manufacturing schedule are needed.

[0074] In some implementations, for example, CAD program 116 checks for excessive vibrations 330 in the numerical simulation results from numerical simulation 315. Machining vibrations (also known as chatter) correspond to the relative movement between the workpiece and the cutting tool, which generates waves on the machined surface. The amount of vibration considered excessive can be determined by analyzing data generated from cutting forces and cutting dynamics models. Cutting force models and dynamics can be used to predict the cutting forces and dynamic responses (including vibrations, chatter, etc.) of the tool and workpiece during cutting. The results can be analyzed to discover how much vibration contributes to instability during cutting.

[0075] After predicting the cutting forces and dynamics, these forces can be used to define the load conditions for subsequent FE simulations to verify the predicted results. FE simulations can: (1) indicate, based on the workpiece material, whether the resulting stresses on the workpiece itself are sufficient to break or damage the workpiece; (2) indicate, based on the fixture (also referred to as the workpiece fixture) material, whether the resulting stresses on the fixture are sufficient to damage the fixture or cause instability in the fixture; and (3) indicate, based on the cutting tool material, whether the resulting stresses on the cutting tool are sufficient to break or damage the cutting tool itself. Any of these three indications from the FE simulation will constitute excessive vibration requiring corrective action to address, such that the amount of vibration during the actual subtractive manufacturing process does not damage the workpiece, fixture, and / or tool.

[0076] If the vibration is too high, two or more layers and therefore two or more manufacturing stages can be modified, for example, by CAD program 116 335. This may involve changing the height of two or more of the layers and / or increasing the number of layers to reduce the height of all layers. As mentioned above, fewer layers are preferred because more layers mean more transitions between AM and SM tools. Therefore, modification 335 is made to balance productivity and problems caused by not having suitable tools (long and strong enough) to complete the machining in a given layer. Other and / or additional modifications 335 are also possible, including adjusting the amount of excess material 340 (as described in more detail below), changing the vibration frequency by adjusting the tool operation (e.g., spindle speed, number of teeth, and relative position, etc.), and / or changing the tool (modifying angles, dimensions, surface treatment, etc.).

[0077] Modifying layer 335 can be based on the available cutting tools and the design of the 3D geometry that requires machining with those tools, to select the number of layers and / or the height of each layer. Simulating the manufacture of part 315 allows us to see how much vibration actually occurs, and based on the numerical simulation results, we modify layer 335, including changing the number of layers to be used (and therefore the manufacturing stage) and / or changing the height of one or more of those layers. Thus, given the size of the part, the available tools, and the simulated vibrations experienced during manufacturing, the process can calculate how and where the part can be divided into multiple layers.

[0078] Additionally, the process can, for example, adjust the amount of the first material added in the first stage, including the portion of the second material removed in the second stage, by means of CAD program 116. Figure 3C A visual representation of the addition and removal of corresponding portions of material in two layers for manufacturing a part is shown. Simulation 310 may include adding a first material 310A using an AM tool in a first stage of the two or more stages, and simulation 315 may include removing a second material 315B using an SM tool in a second stage of the two or more stages, wherein the first stage precedes the second stage, and the second material 315B includes a portion 315B1 of the first material 310A, thereby creating a partially finished (or semi-finished) second layer 316B on top of a fully finished (or semi-finished) first layer. Additionally, simulation 310 may include adding a third material 310B using an AM tool in the second stage of the two or more stages, and simulation 315 may include removing a fourth material 315A using an SM tool in the first stage of the two or more stages, thereby creating a partially finished (or semi-finished) first layer 316A, wherein the first material 310A includes the fourth material 315A, and the second material 315B includes a portion 315B2 of the third material 310B.

[0079] Adjustment 340 involves adjusting the amount of portion 315B1 of the first material 310A included in the second material 315B based on the results of simulations 310 and 315, according to the physical properties of the material, to prevent the part from deviating from its three-dimensional geometry, which would result in insufficient material available for SM operations, including mixing between layers. Therefore, the amount of additional material to be retained can be optimized to reduce material usage and / or manufacturing time. Factors influencing how much non-machined portion of a layer is retained for mixing into the machined portion of the next higher layer may include the strength of the material, the 3D geometry of the part (e.g., the shape and size of different portions of the part relative to each other, such as the aspect ratio of blades and the spacing between blades), and the cutting conditions / parameters of the SM operation.

[0080] Therefore, the process ensures that sufficient material will remain on the manufactured part to allow the first and second layers to be blended during subtractive manufacturing. The thermal effects of the blending process can cause the part to shift or deform, which can adversely affect the quality of the fully manufactured part. By leaving sufficient material on the workpiece during subtractive manufacturing in the first manufacturing stage, the workpiece will be able to absorb heat during additive manufacturing in the second manufacturing stage without deforming too much to ensure that there is insufficient material available for blending the two layers together during subtractive manufacturing in the second manufacturing stage. It should be noted that adjustment 340 may include increasing or decreasing the AM overbuild amount and / or the overlap between AM and SM.

[0081] In the case of SM overlap adjustment, adjustment 340 may include reducing the amount of the fourth material 315A and increasing the portion 315B1 of the first material 310A included in the second material 315B. For example, when numerical simulation determines that the material is not strong and stable enough to prevent deformation that could affect the quality of the manufactured part, more material needs to be left to absorb heat from AM and still have enough material in the correct location for mixing during SM. Therefore, the mixing distance is increased by (e.g., increasing) Figure 2B Overlap 255): Reduce the amount of the fourth material 315A (e.g., reduce the amount of overlap 255): Figure 2B The upper limit of the machining process 222 in the middle) and increase the portion 315B1 of the first material 310A included in the second material 315B (e.g., reduce the ... Figure 2B The lower limit of machining process 232 in the process).

[0082] Additionally, adjustment 340 may include increasing the amount of the fourth material 315A and reducing the portion 315B1 of the first material 310A included in the second material 315B. For example, if numerical simulation determines that the material is strong and stable enough that the workpiece material will not deform, less material needs to be left for mixing. Therefore, the mixing distance is reduced by (e.g., reducing) Figure 2B Overlap 255): Increase the amount of the fourth material 315A (e.g., increase the amount of overlap). Figure 2B The upper limit of the machining process 222 in the middle) and the reduction of the portion 315B1 of the first material 310A included in the second material 315B (e.g., raising) Figure 2B (The lower limit of machining process 232 in the process). Therefore, adjustment 340 may involve changing the toolpath specifications of SM machining used in the first and second stages.

[0083] In the case of AM overbuild adjustment, in addition to changing SM amounts 315A, 315B to leave a sufficient amount of non-machined material in a layer to ensure that AM builds the next higher layer on top and that there is sufficient material in the layer on which the part is SM machined to produce a high-quality manufacturing result, adjustment 340 may include increasing or decreasing the overbuild amount (relative to the three-dimensional geometry of the part) of the first material 310A to be added using additive manufacturing tools in the first stage of the two or more stages. The lateral range of this overbuild amount will depend on the AM process and the materials used.

[0084] Changing the 340AM overbuild amount can be accomplished by altering the toolpath specifications of the AM build or by changing the 3D geometry of the AM build model. For example, the process may include an automated CAD geometry modification step that uses an enlarged version of the part geometry for the AM build in the corresponding layer to generate data as a staged deposition model, and can adjust the required enlargement amount of the AM build (relative to the CAD model of the part) in the corresponding layer of 340 based on numerical simulation results. In other words, the numerical simulation indicates the required enlargement amount of the pre-deformed AM deposition shape in the first manufacturing stage such that after deformation caused by AM in the second manufacturing stage, there will still be sufficient material (beyond the outer surface of the CAD model of the part) to complete the SM in the second manufacturing stage. It should be noted that the enlargement can be vertically upwards from the part geometry (other than laterally outwards) when at least a portion of the top of the added first material 310A needs to be machined away by SM (during the first stage of SM) to create a suitable surface on which a third material 310B will be added (during the second stage of AM).

[0085] In some embodiments, the size of the 340 transition zone and the range of overbuild amount are adjusted in response to numerical simulations 310, 315. In some embodiments, the simulation of thermal effects is based on the different properties of different layers. For example, while this detailed description focuses on manufacturing using a single material, it will be understood that more than one material may be used in a hybrid system, for example, using a single AM ​​tool 176 or more AM tools 176, and part design and / or manufacturing schedules may require the use of different materials in different parts of the part. Therefore, the simulation of thermal effects may take into account the use of different materials (with different physical properties) in a layer relative to an object on which a layer is built, for example, the lower layer (or leaf root) may be a more thermally stable metal than the higher layer placed above it.

[0086] Generally, feedback from numerical simulations combining additive and subtractive manufacturing can be used to adjust manufacturing plans to improve the manufacturing process and / or the quality of the manufactured structure. The number of manufacturing stages and / or the overlap between additive and subtractive manufacturing processes within and between stages can be modified to prevent instability and deformation during additive deposition, ensure uniform material removal during machining, and / or provide stability against vibration and machining dynamics during SM machining. Therefore, the process of improving manufacturing planning by simulating deformation and changing the proportions of added and removed material ensures consistent and accurate part manufacturing using a hybrid manufacturing process.

[0087] The adjusted amounts and / or modified layers / stages may be provided, for example, by CAD program 116 for manufacturing parts using a hybrid additive and subtractive manufacturing system. In some embodiments, the process includes manufacturing part 345 using the adjusted amounts and / or modified layers / stages through a hybrid additive and subtractive manufacturing system. For example, the process may be performed by CAD program 116, which may be coded in at least one non-transitory computer-readable medium and may run on one or more computer processing devices included in the hybrid additive and subtractive manufacturing system. Thus, providing 345 may involve transferring the adjusted amounts and / or modified layers / stages to another part of the process of disposing of manufacturing. Alternatively or additionally, providing 345 may involve saving or storing the adjusted amounts and / or modified layers / stages to a computer-readable medium for later retrieval in manufacturing.

[0088] Additionally, in some embodiments, simulations 310, 315 include simulating the machining of blades or impellers constructed on top of the blade root, which is included as an integral part of the hub. For example, Figure 3D A 3D model 350 is shown of a portion of a turbine rotor having a hub portion 360 and blades 370 designed to operate in high-temperature environments (e.g., 1000 to 5000 degrees Fahrenheit). Figure 3E A proof-of-concept fabrication structure is shown, illustrating a blade 380 partially manufactured on a block 390 representing a hub of a turbine rotor. In high-temperature environments, such as the hot end of an aircraft or other vehicle engine, significant stress exists at the junction of the blade and the hub in the turbine rotor. Therefore, this critical section of the turbine rotor can fail more frequently than other sections, and such failures are more likely to damage the engine than a failure further away in one of the blades 370.

[0089] To address this issue, the design and / or manufacturing plan of the part may include the blade root as an integral part of the hub. For example, the blade root 362 is formed from the same material as part of the hub portion 360, and the blade 372 is constructed on top using a layered and simulation-informed method of hybrid AM+SM manufacturing. This use of the blade root as an integral part of the hub increases the strength of critical parts of the turbine rotor, which may be particularly important depending on the arrangement of hot zones within the part during use. Any problems with weaknesses at the junction between the AM build-up and the initial layers on the cylindrical workpiece are eliminated or transferred from more critical parts of the turbine rotor, thus relieving the problem for the controlled part. In some embodiments, the blade 370 is built on a pre-machined surface (of an over-built preform) to remove stress concentrations from the blade / hub interface.

[0090] Each of the blades 370 may be made of the same material as the hub portion 360 or a different material. Multimaterial deposition is under investigation, but the system and techniques described in this document will be applicable to new developments in the deposition of multiple materials, as the described simulation techniques will be useful in assisting in the selection of materials and their components when developing manufacturing plans based on the performance and operational requirements of the parts in conjunction with the design of the parts. For example, apart from the blades being made of a different material than the hub, the various parts of the hub and / or the various parts of the blades may be made of different materials. It should be noted that the difference between one material and another may lie in that they are alloys of the same group of materials, but the amount of each material used is different.

[0091] In some implementations, numerical simulations of thermal effects include evaluating hot zones (e.g., based on the location of components within the engine) to help determine the optimal height of the blade root, taking into account the materials to be used for the root hub and blades. Numerical simulations of thermal effects may also include helping to determine where and which materials to use, such as using more heat-resistant materials in the hottest parts of components, while also considering component performance and operational requirements.

[0092] In some implementations, the hub with blade roots is manufactured by first casting or forging (hot or cold) a similar design, and then potentially performing conventional SM machining operations. In some cases, the hybrid manufacturing process can begin without initial SM machining operations to prepare the surface for the first deposition, following forging or casting. For example, precision forging or casting can produce a surface ready for the first deposition. In some cases, one or more surfaces of the initial workpiece are prepared for the first deposition by performing end milling using conventional SM machining operations, and then proceeding to the hybrid manufacturing process.

[0093] In some implementations, the hub with the leaf roots is fabricated to include a predefined interface (flat or nearly flat) on the top of each of the leaf roots, which facilitates AM construction of the blades on the leaf roots. For example, a small curvature can be added to each leaf root surface (on which the initial deposition will be performed), wherein the curvature is conformable to the initial hub and concentric with the hub's center of rotation (to intersect / tangentially with the blade to form a smaller diameter root). Conforming the initial shape to the hub shape reduces deposition errors but also complicates the CNC motion of the deposition process.

[0094] In some implementations, maintaining the interface between the blade root and the blade as a flat plane (in the X and Y dimensions of CNC deposition) is preferred, as this simplifies the deposition process. However, in some cases, the flat surface of the blade root may be an angled plane. Generally, the use of a blade root (integrated with the hub) and the design of the interface between the blade root and the blade involve trade-offs between simple and complex machine motion, resulting in more complex deposition and potentially more deposition inefficiencies (e.g., powder loss when using a laser plus powder DED process). These trade-offs can be considered when reaming the benefits of using a blade root, including (1) reducing the risk of failure in this critical area of ​​the bladed disk component by using a known and stable process of conventional SM near the hub and removing the high thermal energy used during deposition from the hub, and / or (2) simplifying the deposition process by reducing the complexity of machine motion during the initial deposition phase.

[0095] exist Figure 3E In the proof-of-concept structure shown, a block (representing the hub of a turbine rotor) is rough-machined to form an initial workpiece with blade roots, including a rough-machined blade root 391. Then, only appropriate subsets of the AM and SM processes (in the three stages of AM+SM hybrid manufacturing) are performed to construct the blade 380. The first blade portion 381 shows the result of AM construction 1 on the blade root 391. The second blade portion 382 shows the result of AM construction 1 and SM semi-finishing 1 (manufacturing stage 1 completed). The third blade portion 383 shows the result of AM construction 2. The fourth blade portion 384 shows the result of AM construction 1 + SM semi-finishing 1 and AM construction 2 + SM semi-finishing 2 (manufacturing stage 2 completed) plus AM construction 3. Finally, the fifth blade portion 385 shows the result of all three manufacturing stages of constructing the blade 380 in three layers on the blade root.

[0096] However, these details of the design and manufacturing plan are not essential. In some implementations, blade roots are not used. For example, a near-identical cylindrical hub (or disc) can be manufactured by casting or forging (hot or cold), and the initial AM build can be on this initial workpiece. This can still reduce overall machine cost and time compared to conventional SM, but part integrity issues may exist at the interface between the blade and the hub (or disc), which may introduce one or more stress concentration zones. Moreover, a significant amount of SM machining will still be required to bring the hub (or disc) to its final shape.

[0097] However, this approach may still be applicable to certain types of parts, depending on their structural strength requirements at the interface between the blade and the hub (or disk). Furthermore, stress concentration issues can be reduced or eliminated through appropriate process control, such as heating the hub before the initial deposition operation to prevent thermal shock, which can cause cracks or weaknesses in the joint and lead to future part integrity problems during operation. Therefore, with proper process control and an understanding of the power source and process, good structural integrity can still be achieved using this method.

[0098] In some implementations, a flat (or near-flat) interface is not used. For example, the initial AM build can be on the final (or near-final) shape of the hub rather than on the blade root, a shape that can be easily obtained by turning a circular feed. This can reduce the total manufacturing time for some types of parts, but in the case of the other method described above, part integrity issues may exist at the interface between the blade and the hub (or disc). Therefore, this method can be used for certain parts, depending on their structural strength requirements at the interface between the blade and the hub (or disc), the complexity of the hub (or disc) surface, and on which the AM build will be performed. It should be noted that both methods described above may have tool accessibility issues, which should also be taken into account, depending on the blade length, twist, and proximity together.

[0099] For example, to determine a suitable hybrid layer manufacturing schedule for blade 372, accessibility issues can be addressed based on the shape of blade 372 and its side blades 371, 373. Shields for the side blades 371, 373 (e.g., outward offsets of the B-Rep of blades 371, 373) can be generated, and collision checks can be performed using these shields to define the working volume for manufacturing blade 372, i.e., the 3D space between the two shields for the side blades 371, 373. The process can then generate toolpaths for blade 372 within this working volume, depending on the type of SM operation (roughing, semi-finishing, or finishing) and the input (e.g., user input) of the SM tool available for that SM operation, which will depend in part on the size and / or shape of blade 372. This toolpath information can be considered during numerical simulation of the hybrid manufacturing process to identify any tool accessibility issues.

[0100] Figure 4 This is a schematic diagram of a data processing system including a data processing device 400, which can be programmed as a client or server. The data processing device 400 is connected to one or more computers 490 via a network 480. Although in Figure 4 Only one computer is shown as data processing device 400, but multiple computers may be used. Data processing device 400 includes various software modules that can be distributed between the application layer and the operating system. These may include executable and / or interpretable software programs or libraries, including tools and services for manufacturing simulation, 3D modeling and manufacturing control programs 404 that implement the systems and technologies described herein. The number of software modules used may vary depending on the implementation. Furthermore, the software modules may be distributed across one or more data processing devices connected by one or more computer networks or other suitable communication networks.

[0101] The data processing device 400 also includes hardware or firmware means including one or more processors 412, one or more additional devices 414, a computer-readable medium 416, a communication interface 418, and one or more user interface devices 420. Each processor 412 is capable of processing instructions for execution within the data processing device 400. In some embodiments, the processor 412 is a single-threaded or multi-threaded processor. Each processor 412 is capable of processing instructions stored on the computer-readable medium 416 or on a storage device such as one of the additional devices 414. The data processing device 400 uses the communication interface 418 to communicate with one or more computers 490, for example, via a network 480. Examples of user interface devices 420 include displays, cameras, speakers, microphones, haptic feedback devices, keyboards, mice, and VR and / or AR devices. The data processing device 400 may, for example, store on the computer-readable medium 416 or one or more additional devices 414 instructions for implementing operations associated with the programs described herein, such as one or more of hard disk drives, optical disk drives, magnetic tape drives, and solid-state storage devices.

[0102] The embodiments of the subject matter and functional operation described in this specification can be implemented in digital electronic circuits, or in computer software, firmware, or hardware (including the structures disclosed in this specification and their structural equivalents), or in a combination of one or more of these. Embodiments of the subject matter described in this specification can be implemented using one or more modules of computer program instructions encoded on a non-transitory computer-readable medium for execution by a data processing device or for controlling the operation of a data processing device. The computer-readable medium can be an manufactured product, such as a hard disk drive in a computer system, or an optical disc sold through retail channels, or an embedded system. The computer-readable medium can be obtained separately, or it can later be encoded with one or more modules of computer program instructions, such as through a wired or wireless network. The computer-readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, or a combination thereof.

[0103] The term "data processing device" encompasses all devices, apparatuses, and machines used for processing data, including, for example, programmable processors, computers, or multiple processors or computers. In addition to hardware, the device may also include code that creates the execution environment of the computer program in question, such as code constituting processor firmware, protocol stacks, database management systems, operating systems, runtime environments, or combinations thereof. Furthermore, the device may employ a variety of different computing model infrastructures, such as network services, distributed computing, and grid computing infrastructures.

[0104] Computer programs (also referred to as programs, software, software applications, scripts, or code) can be written in any suitable programming language, including compiled or interpreted languages, declarative or procedural languages, and can be deployed in any suitable form, including as standalone programs or modules, components, subroutines, or other units suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program may be stored as a portion of a file containing other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple co-located files (e.g., a file storing portions of one or more modules, subroutines, or code). A computer program can be deployed to execute on a single computer, or on multiple computers located in one location or distributed across multiple locations and interconnected via a communication network.

[0105] The processes and logic flows described in this specification can be executed by one or more programmable processors, which execute one or more computer programs to perform functions by manipulating input data and producing outputs. The processes and logic flows can also be executed by dedicated logic circuitry, and the device can also be implemented as dedicated logic circuitry, such as an FPGA (Field-Programmable Gate Array) or an ASIC (Application-Specific Integrated Circuit).

[0106] Processors suitable for executing computer programs include, for example, general-purpose and special-purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor receives instructions and data from read-only memory or random access memory, or both. The basic components of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include one or more mass storage devices for storing data, such as magnetic disks, magneto-optical disks, or optical disks, or operatively coupled to said one or more mass storage devices to receive data from or transfer data to them, or both. However, a computer does not need to have such devices. Additionally, a computer may be embedded in another device, such as a mobile phone, a personal digital assistant (PDA), a mobile audio or video player, a game console, a global positioning system (GPS) receiver, or a portable storage device (e.g., a universal serial bus (USB) flash drive), to name just a few. Suitable devices for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, including, for example: exemplary semiconductor memory devices, such as EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD-ROMs and DVD-ROMs. The processor and memory may be supplemented by dedicated logic circuitry, or the processor and memory may be incorporated into dedicated logic circuitry.

[0107] To provide interaction with a user, embodiments of the subject matter described in this specification can be implemented on a computer having: a display device, such as an LCD (liquid crystal display), an OLED (organic light-emitting diode) display device, or another monitor for displaying information to a user; and a keyboard and pointing device, such as a mouse or trackball, through which the user can provide input to the computer. Other types of devices may also be used to provide interaction with the user; for example, feedback provided to the user may be any suitable form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; and the ability to receive input from the user in any suitable form, including acoustic, speech, or tactile input.

[0108] The computing system may include clients and servers. Clients and servers are generally geographically isolated and typically interact via a communication network. The client-server relationship arises from computer programs running on respective computers and having a client-server relationship with each other. Embodiments of the subject matter described in this specification can be implemented in a computing system comprising: back-end components, such as a data server; or middleware components, such as an application server; or front-end components, such as a client computer with a graphical user interface or web browser, through which a user can interact with embodiments of the subject matter described in this specification; or any combination of one or more such back-end components, middleware components, or front-end components. Components of the system may be interconnected via digital data communication (e.g., a communication network) of any suitable form or medium. Examples of communication networks include local area networks (“LANs”) and wide area networks (“WANs”), the internet (e.g., the Internet) and peer-to-peer networks (e.g., ad hoc peer-to-peer networks).

[0109] While this specification contains numerous implementation details, these details should not be construed as limiting the scope of the claimed or claimable content, but rather as descriptions of features specific to particular embodiments of the disclosed subject matter. Certain features described in this specification within the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually in multiple embodiments or in any suitable sub-combination. Furthermore, although features may be described above as functioning in certain combinations and even initially protected by the claims, one or more features from a claimed combination may, in some cases, be separable from said combination, and a claimed combination may involve sub-combinations or variations thereof.

[0110] Similarly, although the operations are depicted in a specific order in the accompanying drawings, this should not be construed as requiring such operations to be performed in the specific order shown or in an ordered sequence, or that all shown operations be performed to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Furthermore, the separation of the various system components in the above embodiments should not be construed as requiring this separation in all embodiments, and it should be understood that the described program components and systems may be substantially integrated together in a single software product or packaged into multiple software products.

[0111] Therefore, specific embodiments of the invention have been described. Other embodiments are within the scope of the appended claims.

Claims

1. A computer-aided design method for hybrid additive and subtractive manufacturing, the method comprising: To obtain data on the three-dimensional geometry of a part to be manufactured from material using a hybrid additive and subtractive manufacturing system comprising additive manufacturing tools and subtractive manufacturing tools, using a manufacturing process comprising a series of two or more stages, each of the two or more stages comprising adding the material with the additive manufacturing tools and removing some of the material with the subtractive manufacturing tools; Simulating at least a portion of the manufacturing process based on the data and the physical properties of the material, the at least a portion comprising adding a first material using the additive manufacturing tool in a first stage of the two or more stages and removing a second material using the subtractive manufacturing tool in a second stage of the two or more stages, wherein the first stage precedes the second stage, wherein the second material comprises a portion of the first material, wherein removing the second material comprises mixing between the materials added in the first stage and the second stage, and wherein the simulation comprises simulating the thermal effects of adding and removing the materials in the first stage and the second stage; Based on the physical properties of the material, the amount of the portion of the first material included in the second material is adjusted according to the results of the simulation to prevent the part from deviating from the three-dimensional geometry during the manufacturing process, such deviation resulting in insufficient material available for the mixing; as well as The amount of the portion of the first material included in the adjusted second material is provided for manufacturing the part by the hybrid additive and subtractive manufacturing system.

2. The computer-aided design method of claim 1, wherein the portion of the manufacturing process includes using the additive manufacturing tool to add a third material in the second stage of the two or more stages and using the subtractive manufacturing tool to remove a fourth material in the first stage of the two or more stages, the first material comprising the fourth material, the second material comprising a portion of the third material, the simulation comprising simulating vibrations experienced at least during the removal of the second material, and the method comprising: In response to excessive vibration, two or more layers and thus the two or more stages are modified.

3. The computer-aided design method as described in claim 2, wherein simulating vibration includes simulating instabilities during cutting based on predicted cutting forces and dynamic responses.

4. The computer-aided design method of claim 1, wherein adjusting the amount of the portion of the first material included in the second material comprises increasing the amount of over-build of the first material to be added using the additive manufacturing tool in the first stage of the two or more stages relative to the three-dimensional geometry of the part.

5. The computer-aided design method of claim 1, wherein the portion of the manufacturing process includes using the additive manufacturing tool to add a third material in the second stage of the two or more stages, and using the subtractive manufacturing tool to remove a fourth material in the first stage of the two or more stages, the first material comprising the fourth material, the second material comprising a portion of the third material, and adjusting the amount of the portion of the first material included in the second material comprises decreasing the amount of the fourth material and increasing the amount of the first material included in the second material.

6. The computer-aided design method of claim 1, wherein the part is a turbine rotor, the turbine rotor comprising a hub and blades designed to operate in a high-temperature environment, and the simulation comprises simulating the machining of the blades constructed with the additive manufacturing tool on top of the blade root, which is an integral part of the hub, in the two or more stages.

7. The computer-aided design method of claim 1, wherein the computer-implemented method includes manufacturing the part using the hybrid additive and subtractive manufacturing system, wherein the hybrid additive and subtractive manufacturing system includes one or more computer processing devices, the one or more computer processing devices including at least one non-transitory computer-readable medium, the at least one non-transitory computer-readable medium encoding a computer-aided design program operable to perform the acquisition, the simulation, the adjustment, the provisioning, and the manufacturing.

8. A computer-aided design system for hybrid additive and subtractive manufacturing, the system comprising: A data processing device, the data processing device including at least one hardware processor; as well as A non-transitory computer-readable medium that encodes instructions for a computer-aided design program, the instructions being configured to cause the data processing device to perform the following operations: To obtain data on the three-dimensional geometry of a part to be manufactured from material using a hybrid additive and subtractive manufacturing system comprising a series of two or more stages, each of the two or more stages including adding the material using the additive manufacturing tool and removing some of the material using the subtractive manufacturing tool. Simulating at least a portion of the manufacturing process based on the data and the physical properties of the material, the at least a portion comprising adding a first material using the additive manufacturing tool in a first stage of the two or more stages and removing a second material using the subtractive manufacturing tool in a second stage of the two or more stages, wherein the first stage precedes the second stage, wherein the second material comprises a portion of the first material, wherein removing the second material comprises mixing the materials added in the first stage and the second stage, and wherein the simulation comprises simulating the thermal effects of adding and removing the materials in the first stage and the second stage. Based on the physical properties of the material, the amount of the first material included in the second material is adjusted according to simulation results to prevent the part from deviating from its three-dimensional geometry during certain parts of the manufacturing process, such deviation resulting in insufficient material available for the mixing. The amount of the portion of the first material included in the adjusted second material is provided for manufacturing the part by the hybrid additive and subtractive manufacturing system.

9. The system of claim 8, wherein the portion of the manufacturing process includes using the additive manufacturing tool to add a third material in the second stage of the two or more stages, and using the subtractive manufacturing tool to remove a fourth material in the first stage of the two or more stages, the first material comprising the fourth material, the second material comprising a portion of the third material, the simulation comprising simulating vibrations experienced at least during the removal of the second material, and the instructions being configured to cause the data processing device to modify the two or more layers and thus the two or more stages in response to excessive vibrations.

10. The system of claim 8, wherein the instructions are configured to cause the data processing device to adjust the amount of the portion of the first material included in the second material by increasing the amount of over-build of the first material to be added using the additive manufacturing tool in the first stage of the two or more stages relative to the three-dimensional geometry of the part.

11. The system of claim 8, wherein the portion of the manufacturing process includes adding a third material using the additive manufacturing tool in the second stage of the two or more stages, and removing a fourth material using the subtractive manufacturing tool in the first stage of the two or more stages, the first material comprising the fourth material, the second material comprising a portion of the third material, and the instruction is configured to cause the data processing device to adjust the amount of the portion of the first material included in the second material by decreasing the amount of the fourth material and increasing the portion of the first material included in the second material.

12. The system of claim 8, wherein the component is a turbine rotor comprising a hub and blades designed to operate in a high-temperature environment, and the instructions are configured to cause the data processing device to simulate the machining of the blades, constructed with the additive manufacturing tool, on top of the blade root, which is an integral part of the hub, in the two or more stages.

13. The system of claim 8, wherein the system includes the hybrid additive and subtractive manufacturing system, and wherein the instructions are configured to cause the data processing device to manufacture the part using the hybrid additive and subtractive manufacturing system.

14. A non-transitory computer-readable medium that encodes instructions operable to cause a data processing device to perform operations, the operations including: To obtain data on the three-dimensional geometry of a part to be manufactured from material using a hybrid additive and subtractive manufacturing system comprising additive manufacturing tools and subtractive manufacturing tools, using a manufacturing process comprising a series of two or more stages, each of the two or more stages comprising adding the material with the additive manufacturing tools and removing some of the material with the subtractive manufacturing tools; Simulating at least a portion of the manufacturing process based on the data and the physical properties of the material, the at least a portion comprising adding a first material using the additive manufacturing tool in a first stage of the two or more stages and removing a second material using the subtractive manufacturing tool in a second stage of the two or more stages, wherein the first stage precedes the second stage, wherein the second material comprises a portion of the first material, wherein removing the second material comprises mixing between the materials added in the first stage and the second stage, and wherein the simulation comprises simulating the thermal effects of adding and removing the materials in the first stage and the second stage; Based on the physical properties of the material, the amount of the portion of the first material included in the second material is adjusted according to the results of the simulation to prevent the part from deviating from the three-dimensional geometry during the manufacturing process, which would result in insufficient material available for the mixing. as well as The amount of the portion of the first material included in the adjusted second material is provided for manufacturing the part by the hybrid additive and subtractive manufacturing system.

15. The non-transitory computer-readable medium of claim 14, wherein said portion of the manufacturing process includes using the additive manufacturing tool to add a third material in the second stage of the two or more stages and using the subtractive manufacturing tool to remove a fourth material in the first stage of the two or more stages, the first material comprising the fourth material, the second material comprising a portion of the third material, the simulation comprising simulating vibrations experienced at least during the removal of the second material, and the operation comprising: In response to excessive vibration, the two or more layers and therefore the two or more stages are modified.

16. The non-transitory computer-readable medium of claim 15, wherein the simulated vibration comprises simulating instabilities during cutting based on predicted cutting forces and dynamic responses.

17. The non-transitory computer-readable medium of claim 14, wherein adjusting the amount of the portion of the first material included in the second material comprises increasing the amount of over-build of the first material to be added using the additive manufacturing tool in the first stage of the two or more stages relative to the three-dimensional geometry of the part.

18. The non-transitory computer-readable medium of claim 14, wherein the portion of the manufacturing process includes using the additive manufacturing tool to add a third material in the second stage of the two or more stages, and using the subtractive manufacturing tool to remove a fourth material in the first stage of the two or more stages, the first material comprising the fourth material, the second material comprising a portion of the third material, and adjusting the amount of the portion of the first material included in the second material comprises decreasing the amount of the fourth material and increasing the amount of the first material included in the second material.

19. The non-transitory computer-readable medium of claim 14, wherein the part is a turbine rotor comprising a hub and blades designed to operate in a high-temperature environment, and the simulation comprises simulating the machining of the blades constructed using the additive manufacturing tool on top of the blade root, which is an integral part of the hub, in the two or more stages.

20. The non-transitory computer-readable medium of claim 14, wherein the operation includes manufacturing the part using the hybrid additive and subtractive manufacturing system.

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