Method of manufacturing molded layered product

Abstract

The present invention provides a method of manufacturing a molded layered product, comprising: performing three-dimensional printing of a first mold to provide a wall surrounding an exterior of an interior space, the interior space defining a layer of the product, the height of the wall defining the height of the interior space; filling the interior space of the three-dimensionally printed first mold to the height by pouring a casting material, the interior space within the wall forming a first layer of the product; hardening the first layer; finishing the upper surface of the first layer; performing three-dimensional printing of a second mold on the finished surface of the hardened first layer to provide a second wall surrounding the exterior of a second interior space, the second interior space defining a second layer of the product, the height of the second wall defining a second height of the second interior space; a molded layered product is formed by covering the first layer with more casting material, filling a second interior space of the three-dimensionally printed second mold to a second height, forming a second layer on top of the first layer, where the casting material comprises a paste comprising a ceramic or metal.

Description

[0001] This application is a divisional application of the application with application number 201880043485.9 (PCT application number PCT / IL2018 / 050475), application date April 30, 2018, and invention title "Molding Method and Equipment, Especially Suitable for Metals and / or Ceramics". Technical Field

[0002] The present invention, in some of its embodiments, relates to a process and equipment for the additive manufacturing of metal and ceramic components. Background Art

[0003] Currently, additive manufacturing or 3D printing is widely used for manufacturing prototype components and for small-scale manufacturing. Fused deposition modeling (FDM) is a widely used technique in which a plastic filament is unwound from a coil, melted, and extruded through a nozzle that deposits it in a flat line form to form a layer that ultimately emerges as a three-dimensional object.

[0004] Another technique in use is stereolithography. Stereolithography is an additive manufacturing process that works by focusing an ultraviolet (UV) laser onto a vat of photosensitive polymer resin. With the aid of computer-aided manufacturing or computer-aided design software (CAM / CAD), the UV laser is used to draw a pre-programmed design or shape on the surface of the photosensitive polymer vat. Since the photosensitive polymer is photosensitive under ultraviolet light, the resin cures and forms a single layer of the desired three-dimensional object. The process is repeated for each layer of the design until the three-dimensional object is complete.

[0005] Selective laser sintering (SLS) is another additive manufacturing layer technique and involves the use of a high-power laser, such as a carbon dioxide laser, to fuse small particles of plastic into an object with a desired three-dimensional shape. The laser selectively melts the powdered material by scanning cross-sections generated from a three-dimensional digital description of the part (e.g., from a CAD file or scan data) on the surface of a powder bed. After each cross-section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top, and the process is repeated until the part is complete.

[0006] Due to the relatively high melting temperatures of metal and ceramic materials, it is more difficult to use metal and ceramic materials in additive manufacturing processes.

[0007] Because of the build process of forming the part layer by layer, additive manufacturing techniques are generally slow compared to traditional production processes, such as machining, etc.

[0008] DMLS - Direct Metal Laser Sintering is a widely used metal printing technology. A very thin layer of metal powder is spread over the surface to be printed. A laser moves slowly and steadily across the surface to sinter the powder. Then additional powder layers are applied and sintered, thus "printing" a cross-section of the object at a time. In this way, DMLS gradually builds a three-dimensional object through a series of very thin layers.

[0009] Another method of three-dimensional metal printing is Selective Laser Melting (SLM), where a high-power laser fully melts each layer of metal powder, rather than just sintering it. Selective Laser Melting produces very dense and strong printed objects. Selective Laser Melting can only be used with certain metals. The technology can be used for the additive manufacturing of stainless steel, tool steel, titanium, cobalt-chromium alloys, and aluminum components. Selective Laser Melting is a very high-energy process because each layer of metal powder must be heated above the melting point of the metal. The high temperature gradients that occur during SLM manufacturing can also cause stresses and misalignments within the final product, potentially damaging its physical properties.

[0010] Electron Beam Melting (EBM) is an additive manufacturing process very similar to Selective Laser Melting. Like SLM, it produces very dense models. The difference between the two technologies is that EBM uses an electron beam rather than a laser to melt the metal powder. Currently, Electron Beam Melting can only be used with a limited number of metals. Although cobalt-chromium can also be used, titanium alloys are the main raw materials for this process.

[0011] The above metal printing technologies are expensive, very slow, and limited by build size and the materials that can be used.

[0012] Binder Jetting three-dimensional printing technology is widely used to print sand molds for castings or to produce complex ceramic components. It is also known as a metal additive manufacturing technology. Instead of melting the material, as is done in Selective Laser Melting (SLM) or Electron Beam Melting (EBM), the metal powder is selectively bonded with an adhesive ink and then partially sintered and infiltrated.

[0013] In some cases, the metal binder jetting technology is limited to composite metal alloys, especially for stainless steel - bronze composites.

[0014] Hosnnavis et al. disclose a technology for ceramic printing in "Three-Dimensional Printing of Ceramics by Selective Inhibition of Sintering", where, like with metals, an inhibition material forms a boundary defining an edge around a layer of ceramic powder, and then sintering is carried out. Subsequently, the inhibition layer is removed.

[0015] U.S. Patent Publication No. 2014 / 0339745A1, issued to Stuart Ulan, discloses a method of casting an object using a mold, the method including applying a slip mixture to a mold fabricated using "additive manufacturing", and then firing the mold with the mixture therein. The disclosure discusses a composition having a weight percentage of calcium aluminate and filler of 10 - 60%.

[0016] Rapid prototyping and manufacturing by gelcasting of metals and ceramic slurries, published by Stumpf et al. in Materials Science and Engineering A334 (2002) 187 - 192, discloses making a wax pattern using additive manufacturing and then introducing a slurry containing the final part material in powder form.

[0017] Powder injection molding (PIM) is a conventional process where fine - powdered metal (in MIM - metal injection molding) or ceramic (in CIM - ceramic injection molding) is mixed with a quantity of binder material to form a feedstock capable of being processed by injection molding. The molding process allows complex parts with overhangs to be formed in a single step and in large volumes, the complex parts being oversized due to the presence of the binder in the feedstock). After molding, the powder - binder mixture undergoes a debinding step to remove the binder and is sintered to densify the powder. The final product is small components for various industries and applications. The properties of the PIM feedstock flow are defined using rheology. Current equipment capabilities require the processing to be limited to products that can be molded using a typical amount of 100 grams or less per injection into the mold. The variety of materials that can be implemented in PIM feedstock is extensive. Subsequent conditioning operations are performed on the molded shape, where the binder material is removed, and the metal or ceramic particles are diffusion - bonded and densified to the desired state with a typical 15% shrinkage rate in each dimension. Since PIM parts are made using precision injection molds, similar to those used for plastics, the tools can be quite expensive. Thus, PIM is typically only used for larger - volume parts.

[0018] There is a particular desire to find an effective method of performing additive manufacturing using ceramics and metals that is relatively fast, capable of creating complex geometries, and compatible with a variety of materials. SUMMARY OF THE INVENTION

[0019] To create shapes that have not been achievable with traditional molding or machining techniques heretofore, or to use materials that are difficult or impossible to use with known additive manufacturing techniques, or to form shapes faster than known additive manufacturing techniques, this embodiment relates to combining additive manufacturing and molding techniques.

[0020] In an embodiment, additive manufacturing is used to fabricate a mold, and then the mold is filled with the material of the final product. In some embodiments, the layers of the final product are separately constructed with individual molds, where a subsequent layer is fabricated on a previous layer. The previous layer can actually support the mold of the new layer and provide the base plate for the new layer.

[0021] In one embodiment, a printing unit is provided that has a first nozzle for three-dimensionally printing a material to form the mold and a second separate nozzle for providing the filler. The second nozzle can be adjusted to provide openings of different sizes to effectively fill molds of different sizes. In other embodiments, two separate applicators are provided, one for printing the mold and having three degrees of freedom required for three-dimensional printing, and the other for filling the mold after the mold is formed.

[0022] One embodiment includes the possibility of using an inkjet print head to print the mold by utilizing wax or any other hot-melt or thermosetting or UV-curable material, and leveling the deposited layer of the paste casting through the use of a self-leveling casting material. An alternative method for leveling the casting is to vibrate the casting material after molding, and another alternative method includes using mechanical tools (such as a spatula or a scraper) to fill and level the mold.

[0023] According to one aspect of some embodiments of the present invention, a method of manufacturing a molded layered product is provided, the method comprising:

[0024] Performing three-dimensional printing of a first mold to define a layer of the product;

[0025] Filling the three-dimensionally printed first mold with a casting material to form a first layer;

[0026] Performing three-dimensional printing of a second mold on top of the first layer to define a second layer; and

[0027] Filling the three-dimensionally printed second mold with a casting material above the first layer; thereby forming a molded layered product.

[0028] The method may include finishing the first layer after forming the second mold and before printing the second mold; thereby forming the second layer on the finished surface of the first layer. Finishing refers to drying or hardening the layer and then smoothing or cutting the surface of the layer to remove excess material, such as excess paste, above the mold.

[0029] In one embodiment, a mold printing material is used to print the mold.

[0030] In one embodiment, the mold printing material has a melting point that is lower than the melting point of the casting material.

[0031] In one embodiment, the casting material includes an element of a first group and an element of a second group. The first group includes wax, binder, hardening material, a dispersant, an antifoaming agent, a monomer, an oligomer, an initiator, an activator, a stabilizer, a debinding control additive, and a sintering control agent. The second group includes ceramics and metals.

[0032] In one embodiment, the casting material includes a lubricant material, or a casting gel material or a paste material.

[0033] In one embodiment, the mold printing material includes a viscosity that is higher than the viscosity of the casting material.

[0034] In one embodiment, the lubricant or casting gel or paste is water-based or organic solvent-based and can be an energy-activated material.

[0035] In one embodiment, the casting material includes a hydrophilic or a hydrophobic component.

[0036] In one embodiment, the filling includes pouring the casting material into the mold.

[0037] In one embodiment, the pouring is from a pouring nozzle.

[0038] The method may include selecting the pouring nozzle according to the size of a space in the mold to be filled.

[0039] In one embodiment, the filling includes injection molding of the casting material into the mold. In one embodiment, the filling includes using a squeegee or a spatula to spread the casting material into the mold. This embodiment can use a squeegee or a spatula that contacts the mold surface and grabs or pushes the paste. Another method is to keep the squeegee or spatula a little above the mold surface and grab the paste without contacting the surface.

[0040] In one embodiment, at least two different casting materials are used in different layers.

[0041] According to a second aspect of the present invention, there is provided a three-dimensional printing device for printing a mold and filling the mold. The three-dimensional printing device includes:

[0042] A first nozzle, having a first size, for three-dimensionally printing the mold using a first mold material; and

[0043] A second nozzle, having a second size different from the first size, for pouring a material to fill the mold.

[0044] According to a third aspect of the present invention, there is provided a three-dimensional printing device for printing the mold and filling the mold, the three-dimensional printing device comprising:

[0045] A nozzle for three-dimensionally printing the mold using a mold material; and

[0046] A squeegee for pasting a filling material to fill the mold.

[0047] According to a fourth aspect of the present invention, there is provided a three-dimensional printing device for printing the mold and filling the mold, the three-dimensional printing device comprising:

[0048] A nozzle for three-dimensionally printing the mold using a mold material;

[0049] A sealing cover for sealing the mold; and

[0050] An injection molding unit for injecting a filling material to fill the mold.

[0051] According to a fifth aspect of the present invention, there is provided a method of manufacturing a laminated molded product, the method comprising:

[0052] Preparing a plan view of the laminated molded product;

[0053] Cutting the plan view into a plurality of layers;

[0054] Planning a mold for each layer;

[0055] For each successive layer, three-dimensionally printing a respective planned mold; and

[0056] For each successive layer, after forming the respective three-dimensionally printed mold, pouring a casting material into the three-dimensionally printed mold to form the respective layer; and

[0057] Three-dimensionally printing successive layer molds on respective successive layers.

[0058] The method may further comprise hardening each layer before printing a successive laminated mold thereon, additionally or alternatively, comprising polishing respective layers before forming a subsequent layer thereon.

[0059] The casting material is selected to have rheological properties to flow and fill the mold and adhere to an inner surface of the mold.

[0060] The method may use heat to stabilize the product after all layers of the product have been formed

[0061] The method may include removing respective mold layers.

[0062] The method may include heating or using a solvent to remove sacrificial material from the casting material.

[0063] In one embodiment, the casting material includes a powder, and the method includes applying a heat treatment to sinter the powder. A hot isostatic pressing process (HIP) may be used to increase the density of the casting material.

[0064] According to a sixth aspect of the present invention, there is provided a molded component or product made of metal or ceramic.

[0065] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, exemplary methods and / or materials are described below. In case of conflict, the patent specification and its definitions shall prevail. Additionally, the materials, methods, and examples are illustrative only and not necessarily limiting.

[0066] The operation of the three-dimensional printing device according to an embodiment of the present invention may include manual, automatic, or a combination thereof to perform or complete selected tasks. Additionally, according to the actual instrument and the device of the embodiment of the method and / or system of the present invention, several selected tasks can be implemented using an operating system through hardware, through software, or through firmware, or through a combination thereof.

[0067] For example, the hardware for performing selected tasks according to an embodiment of the present invention can be implemented as a chip or a circuit. As software, the selected tasks according to an embodiment of the present invention can be implemented as multiple software instructions executed by a computer using any suitable operating system. In an exemplary embodiment of the present invention, one or more tasks are executed by a data processor according to the exemplary embodiments of the method and / or system described herein, such as a computing platform for executing multiple instructions. Optionally, the data processor includes volatile memory for storing instructions and / or data and / or non-volatile memory for storing instructions and / or data, such as a magnetic hard disk and / or a removable medium. Optionally, a network connection is also provided. Optionally, a display and / or a user input device, such as a keyboard or a mouse, are also provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The present invention is described herein by way of example only with reference to the drawings. Referring now particularly to the drawings, it should be emphasized that the details shown are by way of example and for purposes of illustrative discussion of embodiments of the present invention. In this regard, the description with reference to the drawings renders how embodiments of the present invention may be practiced apparent to those skilled in the art.

[0069] In the drawings:

[0070] Figure 1A The embodiment according to the present invention is a simplified flowchart illustrating a procedure for manufacturing a laminated molded product or component.

[0071] Figure 1B Is a display Figure 1A A more detailed embodiment of the procedure.

[0072] Figure 2 Is a simplified view showing a plan view of a component to be produced using this embodiment.

[0073] Figure 3 The embodiment according to the present invention is a simplified view showing an exemplary manner of cutting Figure 2 The component for layer manufacturing.

[0074] Figure 4 Is a display for manufacturing Figure 2 A simplified view of the printing mold for the first layer of the component.

[0075] Figure 5 Is a display for forming Figure 2 The first layer of the component in Figure 3 A simplified view of the casting of the mold produced.

[0076] Figure 6 Is a display Figure 2 A simplified view of the printing of the mold for the second layer of the component.

[0077] Figure 7 Is an illustration Figure 6 A simplified view of the casting of the mold produced.

[0078] Figure 8 Is a simplified view showing the component produced according to Figure 2 After removing the mold.

[0079] Figure 9 The embodiment according to the present invention is a simplified view of a dual-station linear device for manufacturing a laminated molded component or product.

[0080] Figure 10 Is Figure 9 A variant of the device, in which the mold printing and pouring applicator are combined into a single operating applicator.

[0081] Figure 11 And Figure 12 Are respectively Figure 9 The front view and top view of a variant of the device, Figure 9 The device has a printing station, a pouring station, and two platforms, each platform being located on a separate track.

[0082] Figure 13 is based on a four-station turntable Figure 9 variant of the device.

[0083] Figure 14 is Figure 9 a variant of the device, Figure 9 The device of also incorporates a surface finishing station using a roller that can be selectively heated.

[0084] Figure 15 is Figure 9 a variant of the device, in which a squeegee or spatula contacts the mold surface and spreads paste to fill the mold.

[0085] Figure 16 is Figure 15 a variant of the device, in which the squeegee is lifted above the mold surface.

[0086] Figure 17 is Figure 9 a variant of the device that further includes a cutter.

[0087] Figure 18 According to an embodiment of the present invention is Figure 9 a variant of the device, in which injection molding is used to fill a printed layered mold.

[0088] Figure 19 According to an embodiment of the present invention is a flowchart of a program for detecting and correcting faulty layers as shown. Detailed Description

[0089] In some embodiments, the present invention relates to processes and equipment for the additive manufacturing of metals and ceramics.

[0090] Before explaining in detail at least one embodiment of the present invention, it is to be understood that the application of the present invention is not necessarily limited to the details of the construction and arrangement of components and / or methods set forth in the following description and / or illustrated in the drawings and / or examples. The present invention is capable of other embodiments or of being practiced or carried out in various ways.

[0091] Now referring to the drawings, Figure 1A According to this embodiment is a simplified flowchart showing a method of manufacturing a molded layered product. The first block 10 indicates printing a first mold to define a layer of the product. The mold can be printed using known additive manufacturing techniques, which will be discussed in more detail below. Block 12 represents pouring a casting material to fill the mold printed in block 10. The casting material then may form a first layer of the final molded layered product.

[0092] In block 14, a second layer of the mold is then printed on the first layer and / or the first molded layer. In some cases, the second layer is smaller than the first layer in at least one dimension such that the second layer of the mold is deposited on the casting of the first layer. As will be discussed in more detail below, the casting layer may harden to support the printing, or the printing of the second layer of the mold may wait until the first layer is dry enough or hardened to support the second layer of the mold.

[0093] In block 16, more casting material is poured into the second layer of the mold to form the second layer of the product. As shown in block 18, the process is repeated as many times as needed to form a molded layered product having the desired number of layers. It should be understood that the different layers may be of different thicknesses.

[0094] After pouring, the new surface of the casting layer may be selectively finished or polished with the finishing tools shown at 20 and 22.

[0095] Any standard mold printing material having sufficient strength to hold the casting material at the casting temperature and other casting conditions can be used to print the mold. Any standard 3D printing technique, such as fused deposition modeling (FDM) or inkjet printing, can be used to print the mold.

[0096] In an embodiment, the mold printing material has a melting point temperature that is lower than the melting point of the casting material such that the mold can be removed using heat once the product is ready. For example, wax can be used for the mold, and the casting material can be any suitable casting material having a higher melting point than wax. If sintering is used, the casting material can be any material that can be sintered, including ceramics, metals, and in some cases plastics.

[0097] Similarly, any material that can be used in the green stage can be used, and such materials are particularly useful for ceramic molds.

[0098] In an embodiment, the process may heat above a desired temperature. Therefore, a cooling process, such as using an air flow, can be used.

[0099] The casting material can generally be any material that can fill a mold and can then be given the desired properties of the product by, for example, drying or cooling, or by any energy-activated transformation reaction or sintering. The hardening methods can include evaporation or activation reactions, including energy activation, thermosetting, or UV curing, etc. IR, microwave, or UV radiation can be used, as well as blowing with hot air.

[0100] In an embodiment, the casting material may be an activated wax or a mixture of monomers or oligomers that are hardened, or a polymer emulsion or dissolved polymer that is dried to harden the casting material, along with a ceramic powder or a metal powder or a mixture of materials. Thus, the layer may be formed from a mixture of materials to achieve specific mechanical or other properties. The final product may then be heated to melt the mold material, or may be immersed in a solvent to dissolve the mold, and then may be immersed in a solvent to filter out some of the additives, and may be heated to a higher temperature to remove the binder and may also be further sintered to fuse the powder, and may even be subjected to other common heat treatments such as HIP (Hot Isostatic Pressing). Thus, this embodiment may provide a method for fabricating molded ceramic or metal or compound products.

[0101] A slip, slurry or paste mixture is ceramic or / and metal particles, optionally a mixture of several powders, in a suspension of a liquid carrier, such as water or an organic solvent, such as polyolefins, alcohols, ethylene glycol, polyethylene glycol, ethylene glycol ethers, ethylene glycol acetate ethers and others, and the casting material may contain a mixture, such as an aqueous-based or solvent-based composition up to 60 - 95% by weight of a powder or powder mixture.

[0102] Gel casting is a ceramic forming technique used to fabricate high-performance complex-shaped ceramic products. The processes used in gel casting are similar to those often used in traditional ceramic forming processes but are adapted to achieve high strength and good mechanical properties. Gel casting involves using a slurry that contains the final part material in powder form, and involves steps such as removing internal air bubbles to achieve the desired properties.

[0103] The paste is a dispersion of powder and organic material in a liquid and may have rheological properties to be able to flow from one side and fill the mold, and to be able to be properly laid on the deposited mold material at the mold interface surface.

[0104] In the gel casting hardening process, the casting material has shear thinning and thixotropy to ensure proper flow and filling of the mold. To increase the viscosity of the slip and to cure the hot casting material as soon as it is deposited, the temperature of the pre-molded and casting material is kept low. The casting material and the mold material are immiscible. Embodiments may use an aqueous-based slip material with a hydrophobic casting material and vice versa. Some surface wetting characteristics may be retained to control and replicate smaller feature sizes.

[0105] A mold design method can allow for reducing the load of the mold material on the slip casting material. Engineering of the design process may ensure that the weight of the deposited mold material is distributed over as large an area as possible to support the structure.

[0106] An additional hardening procedure can use an energy activation process, i.e., hardening of the deposited slip, which may be achieved using methods such as thermal curing, UV curing, by intervening to change physical conditions such as drying or polymerization transition reactions, to implement the hardening procedure.

[0107] In an embodiment, the mold printing material may have a viscosity higher than that of the casting material, such that the mold remains intact when the casting material is injected. The casting material may have good wettability to properly fill the mold.

[0108] In an embodiment, the casting material may have a low viscosity at room temperature and good wetting ability for the mold material. The casting material may be hardened after deposition using methods such as thermal curing, UV curing through drying or polymerization transition reactions. The casting material may also have a low shrinkage rate and good debinding properties.

[0109] In an embodiment, the casting material may include a hydrophilic or hydrophobic component.

[0110] Processes such as gel casting or drying or polymerization transition reactions can be used to create a product with a strong layered bond without mechanical or chemical defects.

[0111] Casting or pouring may be carried out at a high temperature, strictly controlling the materials to provide the necessary mechanical properties. Pouring may use a liquid dispensing system consisting of a dispensing control unit. The quantity of the filling material may be set according to parameters of the sub - mold, such as volume, overflow coefficient, etc. Then, the casting material may be leveled by mechanical means, such as a squeegee or spatula, or with an optional vibration procedure under its self - leveling property.

[0112] After pouring, the material may be energy - activated by IR to a temperature that produces a more stable state, such as a hardened state, in the range of 30–150 °C. Alternatively, the material may be energy - activated by UV, etc. The material thus hardens.

[0113] Later, the sub - mold, i.e., the mold of the individual layer, can be removed by exposing the component to a higher temperature, or using a chemical dissolution process with an acid, or by immersion in a solvent to dissolve the mold material or other processes. For the case of a wax - based mold, the suitable temperature may be in the range of 50–250 °C.

[0114] A degreasing and sintering stage may involve increasing the temperature to degrease and sinter the active part of the casting material, and depending on the actual material and the mechanical properties required for the final product, typical temperatures for degreasing and sintering are in the range of 200°C - 1800°C.

[0115] According to a process proposed in this embodiment, a paste casting material is cast under high shear force and controlled temperature. In this embodiment, the paste casting material may be deposited on the previous layer of the lubricant casting material, and the lubricant casting material is cast with a higher viscosity and hardness and may be cast at a lower temperature.

[0116] Since two consecutive layers are composed of the same material, it can be expected that they share properties. Generally, the casting material is water-based or organic solvent-based and allows the material to disperse.

[0117] Drying, degreasing, and sintering may be carried out in an oven, which may be integrated in a single device or provided individually.

[0118] Now consider in more detail the process according to Figure 1A of the process.

[0119] The process may use a casting material and a mold material. The mold material may be, for example, any material that freezes below 300°C and has a distinct melting point, such as mineral wax. The mold material can be applied by any controlled additive manufacturing tool, such as the FDM or inkjet technology mentioned above, and is thus selected from materials suitable for such processes.

[0120] The casting material may consist of a functional powder dispersed in a sacrificial material. A casting material paste may be selected, and the casting material paste freezes at a lower temperature compared to the melting point of the corresponding mold material and the corresponding gel temperature. For example, a mixture of suitable PEG etc. may be used as the sacrificial material to achieve the necessary combination of freezing point and melting point. Alternatively, a monomer or oligomer may be used for hardening, or alternatively, hardening by drying may be involved, and the monomer or oligomer polymerizes through energy activation and through a transition reaction.

[0121] At a temperature above the freezing temperature and below the melting point temperature of the mold material, a casting material such as a slurry or paste may gel. Alternatively, a self-hardening casting material may be used, such as: epoxy low-viscosity monomers and / or oligomers with suitable hardeners and / or acrylic and / or methacrylic monomers with suitable cross-linking agents.

[0122] To ensure the stability of the first layer of casting material, such as a slurry or paste, the slurry or paste may be designed to have rheological properties such that the still non-flowing material behaves as a stiff gel and includes appropriate shear thinning and thixotropy as needed, such that the viscosity may or may not change.

[0123] The binder material may include a liquid carrier, which is the flowing part of a slurry or paste and serves as a functional hardener, and may contain organic additives at a final stage, which decompose upon drying at <700 °C to be removed when no longer needed.

[0124] The functional powder is the metal or / and metal oxide or ceramic that constitutes the body of the final product. The material may be optionally heat-treated at >500 °C to melt the powder after the sacrificial material has disappeared to form the final solidified body.

[0125] Now refer Figure 1B to, and the process includes the establishment of the mold as shown in block 10, where three-dimensional printing may use any of the following: mineral wax of UV / EB-curable acrylic with m.p. >60 °C, methacrylic acid, thermally curable epoxy resin, polyurethane, etc. to form the mold components.

[0126] A tray is placed in position, and the first layer of mold sub-components is established on the tray.

[0127] The mold is then filled 12 with the casting material in liquid or slurry or paste form. The casting material may be poured into the mold under a high shear force, or in an embodiment, the casting material may be injected into the mold to ensure tight contact with the mold walls, thus ensuring proper and complete filling of the mold. The mechanical strength of the mold itself may be sufficient to withstand the injection force.

[0128] The now-formed (n - 1) sub-parts or layers provide a base for the next, the nth, sub-part.

[0129] It may be necessary to cure or harden 23 the casting material slurry or paste so that the layer can withstand the load of the subsequent layers of mold material. In other cases, the viscosity of the already-formed layer may be sufficient. Curing or hardening can be achieved by using any one or more of the following:

[0130] 1. Keep the temperature of the casting low enough to freeze the slurry or paste that has been cast from the previous layer.

[0131] 2. Harden the casting material slurry or paste using a thermosetting process, such as using epoxy resin and / or acrylic and / or methacrylic crosslinkable monomers.

[0132] 3. Harden the surface of the slurry by activating a polymerization reaction or, in some cases, using the heat from another part of the process.

[0133] 4. Harden the casting material slurry using a drying process, such as a process involving infrared radiation.

[0134] 5. Heat to evaporate the binder material, such as a solvent or water.

[0135] Then continue the process by printing the next mold layer 14.

[0136] The second mold layer may be printed on the surface of the previous casting paste material and may also be built on the mold material from the previous layer.

[0137] In the next stage, fill the second mold layer -16 in a manner similar to that done for the first layer. Curing 24 may also be carried out as required.

[0138] Repeat the stages of hardening, printing, and filling -18 for each additional layer required in the product.

[0139] The hardened casting material paste within the shape of the final product or product part is now embedded in the sub - mold.

[0140] The final part may now be stabilized 25. When the shear force is stopped, the slurry or paste may start to gel and harden, thus imparting green strength to the casting material and / or activating a hardener to impart green strength. Green strength is the mechanical strength that can be imparted to a compacted powder such that the powder can withstand the mechanical operations that the powder undergoes before sintering without damaging its fine details and sharp edges.

[0141] If the gel casting procedure is carried out, the final green strength is generated by thermal polymerization. Thermal polymerization can be carried out at a high temperature above the freezing point of the hardened slurry and below the melting point of the mold material, and under suitable conditions that allow the selection of such a temperature.

[0142] Then the mold material -26 may be removed. Removal may involve heating the product and the mold to the melting point of the mold so that the mold material liquefies and can be collected for reuse. Alternatively, the mold may be removed by chemical dissolution.

[0143] In the production of all die and sub-die components, a water tank can be provided for collecting molten die material, such as mineral wax, for reuse.

[0144] By controllably heating to an optimal temperature, for example, by evaporating and / or decomposing the sacrificial materials, such as carrier liquids and organic additives, once the die is removed, the sacrificial material - 27 of the paste is removed.

[0145] After removing the sacrificial material, the powder of the active material may melt into a solid form. A heat treatment - box 27 - such as sintering, may be used to obtain the desired final properties of the product. As described above, exemplary temperatures between 400°C and 1800°C may be used, especially temperatures above 500°C.

[0146] Now refer to Figure 2 , Figure 2 which is a simplified diagram illustrating a blueprint 30 of a product desired to be manufactured. The product has a lower ring 32, a middle ring 34, and an upper ring 36, where the lower ring has a larger radius, the middle ring has a smaller radius, and the upper ring has a medium radius.

[0147] Now refer to Figure 3 , Figure 3 which illustrates one way of fabricating the product 30. For each layer to be fabricated separately, using the procedure outlined in Figure 1A -B, the product may be decomposed into multiple layers. One possibility is to select a fixed layer thickness and fabricate the number of layers necessary for the fixed thickness, but for this, the upper boundary 38 of the lower ring 32 should exactly fall at a layer boundary, so the layer thickness becomes the Z-axis resolution, which provides a limit for the component dimension in the Z-axis.

[0148] Another possibility is to fabricate each of the rings 32, 34, and 36 as a separate layer, but then a support structure for the die of the third layer may be required, otherwise the third layer would hang in the air.

[0149] In the current example, the ring 32 is fabricated as a single first layer 40, and the two rings 34 and 36 are fabricated together as a single second layer 42.

[0150] Now refer to Figure 4 ,and three-dimensionally print a die 44 for the lower ring portion 32. The die includes a bottom plate 46 and a border 48.

[0151] Figure 5 illustrates the Figure 4the mold 44. The casting material may be a combination of binder and additives, may be a wax and a metal or ceramic powder, and the casting material fills the mold above the base plate 46 within the edge 48. The casting material may be poured from a nozzle 52, which may be part of a dedicated device according to the present embodiment, as will be discussed in more detail below.

[0152] Now refer to Figure 6 , Figure 6 and describe the printing of the second layer according to the example of Figure 2 . Print a single mold part 60 that has a single outer radius that exceeds the radius of the upper ring 36. Internally, a lower portion 62 of the mold 60 has a radius that is equal to the radius of the middle ring 34, and an upper portion 64 of the mold 60 has a radius that is equal to the radius of the upper ring 36. The mold part 60 is located on the surface created by the pouring of the casting layer 50, so the existing surface of the product provides support and no additional support structure is required. As described above, in one embodiment, the viscosity of the casting layer may be sufficient to support the new mold part 60, or in an alternative embodiment, the first layer may be hardened first before placing the new mold part.

[0153] Now refer to Figure 7 , and the upper mold part 60 may be filled with more of the same casting material used for the lower part, thus forming the upper and middle rings of the product. Alternatively, different casting materials may be used for different layers.

[0154] The combination of the mold and the casting may be heated or degummed or sintered to remove the mold and the wax, to remove the binder, and to fuse the powder in the casting material. Finally, after the wax has melted, as shown in Figure 8 , the product 70 is revealed from the casting.

[0155] Now refer to Figure 9 , Figure 9Shows components of a 3D printing and filling apparatus for printing a mold and filling the mold with a casting material. An extruder assembly 80 has a nozzle 81 that has a nozzle size suitable for printing the mold or mold part using a first mold material as described above. For simplicity, one print nozzle 81 is shown, but any suitable number may be provided. The extruder assembly 80 may be, for example, a standard 3D extruder assembly capable of moving in three degrees of freedom. More specifically, three degrees of freedom may be provided for the relative movement between the tray and the applicator, and most FDM printers have an XY workstation for the extruder and a Z-axis. The extruder assembly may have any desired number of nozzles.

[0156] To pour the casting material into the mold once the mold is formed, a casting material applicator 82 is provided and the casting material applicator 82 may include a single pouring nozzle 84. Nozzle 84 is sized to effectively fill the mold with casting material, so the casting material is not applied by the same technique as the mold material. Thus, a relatively rough technique is used for the casting material and a relatively fine technique is used for the mold. The mold defines the geometry and the casting provides the properties of the part. Pouring nozzles may be provided to achieve the required fill volume, minimum diameter, etc.

[0157] Multiple nozzles may be provided to speed up the filling rate and still allow precise filling.

[0158] In one embodiment, in the case where the casting material is a paste, the paste may be poured into the interior or exterior of the cavity and then the cavity may be filled by moving a squeegee along the cavity boundary.

[0159] More specifically, the apparatus may include two main subsystems.

[0160] 1. An additive manufacturing system (AMS) 80, which may be based on FDM, inkjet, and other known methods and fabricate the sub-mold. The system may involve at least three degrees of freedom when referencing the build tray. According to an embodiment of the present invention, the sub-mold may be made of a mineral wax or similar material.

[0161] 2. A liquid dispensing system (LDS) based on a pouring system 82, where the casting material for making the part is cast or poured into the mold. The part material may be metal, ceramic, or any liquid suspension or paste of other materials as described above.

[0162] The casting material in liquid form is dispensed in a controlled manner according to a predetermined value, e.g., depending on the volume of the sub-mold to be filled.

[0163] The position of the pouring system 82 is also determined according to the preferred filling position relative to the sub-mold. The pouring system may typically have at least two degrees of freedom relative to the build tray. In some cases, a third degree of freedom may be provided.

[0164] A vibrating surface may be provided to vibrate the mold and ensure uniform distribution and leveling of the poured material within the mold. A hardening unit, such as an infrared lamp or a hot air unit, may be provided to heat the mold and the casting material and ensure sufficient hardening of the material.

[0165] The first step before producing the component includes preparing digital manufacturing files to reflect the blueprint. The component is divided or sliced into sub-components for the individual layers. For each sub-component, a sub-mold file is prepared.

[0166] Then each sub-mold file is sent to the additive manufacturing system (AMS) for printing. The sub-mold is built on the device tray. Then the tray is moved to the LDS position, and material is dispensed into the sub-mold to fill the defined space inside. Once the process is completed, the device tray returns to the ADS position where the next sub-mold file is sent. The new sub-mold is built on top of the just-poured layer, and the procedure is repeated layer by layer until all sub-components are made.

[0167] There are various methods of generating the sub-files. Each file must be "legal", meaning that a sub-mold can physically be produced by the relevant additive manufacturing method used in the device, and a physical sub-component can be made by inserting casting material into the mold. Non-conforming files may include, for example, mold shapes that are prone to collapsing.

[0168] In one embodiment, the sub-files may be generated according to a selected Z-resolution of the device, meaning a predetermined layer height is selected. For example, if the selected resolution of the device is 0.2 mm, the product may be sliced into individual 0.2 mm sub-component files by the software, and the sub-components are prepared accordingly. The thickness may be varied according to the component geometry quality requirements.

[0169] In another embodiment, the sub-components may be defined according to the maximum sub-mold depth that can be appropriately filled with casting material.

[0170] Additionally, the sub-mold files may be scaled according to the shrinkage rate of the component during the heat treatment process.

[0171] Then the assembly of the sub-molds and sub-components is brought to a heat treatment unit. According to one embodiment, the heat treatment may include the following steps:

[0172] 1. Raise the temperature to melt the wax.

[0173] 2. Immerse in a solvent or gas to dissolve or filter part of the binder and / or raise the temperature for debinding.

[0174] 3. Raise the temperature again for sintering.

[0175] 4. Add heat treatment as required according to the material and quality requirements. For example, hot isostatic pressing may improve the density of the component. Aluminum components can be tempered and aged, etc.

[0176] As an alternative to the above and the use of melting to remove the wax, a solvent may be used to remove the wax. As another option, a combination of melting and using a solvent may be used.

[0177] As shown, the mold component 85 is printed on a tray 86, and the tray 86 is sequentially located on a moving platform 88. The platform moves on a linear axis 90 between the three-dimensional print head 80 and the perfusion nozzle 84. For a single component, the platform may move once per layer between two positions. As an alternative to a linear axis, the platform may be rotatable and may rotate between the two positions.

[0178] In another embodiment, a plurality of workstations may be provided on the path of the platform, so there may be several printing positions and several filling positions, and multiple components may be printed in parallel.

[0179] In another embodiment, a plurality of workstations may be provided on the path of the platform, so there may be several additional process positions, such as an IR workstation, a polishing workstation, etc.

[0180] The perfusion nozzle 84 may be removable and may be interchangeable with other nozzles of different sizes in an embodiment, so that all products of different scales can be effectively filled using an appropriate filling rate.

[0181] Now referring to Figure 10 , Figure 10 shows Figure 9 a simplified diagram of a variant of the device, where the print head 80 and the perfusion nozzle 82 are combined into a single dual-purpose operation unit 89 with a print nozzle 81 and a perfusion nozzle 84, but do not have to be operated simultaneously.

[0182] The unit 89 may have three or more degrees of freedom relative to the tray to print the mold and then fill the mold.

[0183] Figure 11 and Figure 12 are respectively Figure 9 the front view and top view of a variant of a device having a printing station and a pouring station and two platforms, each platform being located on a respective track. Figure 11 is a simplified schematic view showing two trays 90 and 92, each tray in the position below one of the nozzles. Tray 90 is below the print head 94 of the printing die member 96. At the same time, tray 92 is below the pouring unit 98 which pours casting material into the die member 100. Tray 92 may have been previously below the print head 94 to print the die 100. Thus, by filling one die while printing another die, a higher utilization rate of the printer may be achieved.

[0184] In Figure 12 a first tray 110 travels on a first platform 112 carrying a die member 117 between the print head 114 and the pouring unit 116. Similarly, a second tray 118 travels on a second platform 120 carrying a die member 121 between the print head 114 and the pouring unit 116. The trays and platforms travel within a first axis herein referred to as the x direction. The print head 114 and the pouring unit 116 travel within a second axis between the two platforms, the second axis being perpendicular or substantially perpendicular to the travel direction of the platforms. The travel direction of the printing and pouring units is herein denoted as the y direction. Bridges 122 and 124 may respectively carry the head 114 and the pouring unit 116. Similarly, rails or tracks 126 and 128 may carry the platforms 112 and 120. The print head 114 typically has three degrees of freedom relative to the trays and the applicator, and the same applies to all embodiments herein.

[0185] In Figure 12 an embodiment, each platform moves from a die printing position to a pouring position, and the print head and the pouring unit move from one side to the other side, so that each side can be printed and poured in sequence, thereby allowing two components to be manufactured in parallel with a high utilization rate of the print head.

[0186] In one embodiment, the platform may be fixed, and the head may move in the x direction. One of the head or the platform may move in the y direction.

[0187] Now refer to Figure 13 , Figure 13An embodiment of the printing and filling device is described based on a turntable 130, which has four workstations 132, 134, 136 and 138. The turntable rotates and each tray reaches the workstation 132 for printing the molded part and the workstation 134 for filling. Note that during the process itself, the part is fixed. The turntable can rotate by that angle between one workstation and the next between each process. The remaining two workstations 136 and 138 are marked as selective processes. One possibility is that they may be provided with a second print head and filling unit to double the capacity. Another possibility is that workstation 136 may include a finishing unit to finish the surface filled at workstation 134, and workstation 138 may provide heating or sintering in a high-temperature vacuum, which the turntable usually does not include as it takes several hours.

[0188] Other uses of the selective workstations are possible and the turntable is not limited to four workstations. Thus, workstations that can perform various complementary processes in parallel may be added, such as UV curing, IR thermal hardening, hot air drying, microwave drying, cooling, flattening or polishing or finishing, etc.

[0189] Now refer to Figure 14 , Figure 14 which shows a linear embodiment with a third workstation or process position. The platform 141 or the platform of the carrier tray 143 and the mold 145 moves between a first position under the print head 140, a second position under the filling unit 142 and a third position under the roller 144. The roller may smooth the casting material 146 after filling. It will be recalled that the casting material may be of high viscosity and thus may accumulate rather than find its own level like a low-viscosity material. Alternatively, the mold may be deliberately filled to a certain edge above the top of the mold as described elsewhere herein. Thus, flattening may be required before starting the next level or to complete the product or part. The roller may be used to flatten the mold and / or the filling of the mold, i.e., the casting material. To perform the flattening, the roller is heated to a temperature in the exemplary range of 60–140 °C.

[0190] It will be understood that the finishing workstation may be incorporated into both the embodiment using a turntable and the linear embodiment.

[0191] Now refer to Figure 15 , Figure 15Describe another embodiment where the tray 160 holds a mold part or sub - mold 162, and provides a mass of paste 164 to fill the mold. A squeegee 166 wipes across the top of the entire mold, pushing the paste into the spaces 168 in the mold, thus filling the mold and finishing the surface simultaneously. As an alternative to a squeegee, a doctor blade can be used.

[0192] The squeegee may be combined with a dispensing nozzle as an additional workstation so that the use of the dispenser may bring the paste into the space, and then the squeegee may push the paste to fill the space.

[0193] Paste dispensing may be used to provide the mass 164, for example using a paste - dispensing nozzle. The nozzle may dispense material along where the material is needed, and then, the squeegee 166 may push the paste into the cavities in the mold and smooth the layer into place. Alternatively, the paste may be directly dispensed into the cavities, for example using a row of dispensers that move like a print head within the cavities in the mold, and then the layer is smoothed with the doctor blade.

[0194] The row of dispensers may be provided at any desired resolution. The dispenser may move at an angle relative to the movement of the doctor blade or the workstation movement.

[0195] As Figure 15 shown, the squeegee or doctor blade may press on the mold surface.

[0196] Now refer Figure 16 , Figure 16 with Figure 15 the same, except that the squeegee or doctor blade is spaced from the mold surface, for example between 1 and 100 microns, to allow non - contact filling of the mold. As Figure 15 , the tray 160 holds a mold part or sub - mold 162, and provides a mass of paste 164 to fill the mold. The squeegee 166 wipes the paste across the top of the entire mold, pushing it into the spaces 168 in the mold, thus filling the mold and finishing the surface simultaneously. Due to the space between the squeegee and the mold, a thin paste coating may extend over the upper part of the mold surface.

[0197] Now refer Figure 17 , Figure 17Shows an alternative linear embodiment with a third workstation. The platform 141 or the carrier tray 143 moves between a first position below the print head 140, a second position below the perfusion unit 142, and a third position below the polishing or cutting machine 150 of the mold 145. After perfusion and / or molding, the polishing machine cuts off the excess of the casting material 146.

[0198] It should be understood that the polisher may be incorporated into an embodiment using a turntable. The polisher 150 may be a machining tool such as a CNC tool, for example a fly cutter, which passes over the sub-mold and polishes the sub-component after the casting material has been poured and has hardened to a predetermined height, for example 0.05 mm above the upper edge of the sub-mold.

[0199] Now refer to Figure 18 , Figure 18 to illustrate another alternative for filling a mold. The tray 170 carries a sub-mold or part mold 172 containing the space 174 to be filled. The sealing plate 176 is sealed above the mold and includes a pipeline 178 for injection molding into the space. In particular, injection may use powder injection molding (PIM). The powder may be a powder metallurgy (PM) powder, such as a metal injection molding (MIM) powder. For Figure 17 the embodiments and other embodiments described herein, the powder may be a mixture of large and small particles.

[0200] In the linear or turntable embodiments, injection molding may be provided as an additional workstation or may be the main workstation for filling the mold.

[0201] Now refer to Figure 19 , Figure 19 is a simplified flowchart showing the self-test program 180. In the program 180, the last placed layer 182 is inspected. Generally, the inspection may involve a test of smoothness, for example by imaging using a diagnostic camera. If a damage or defect is detected in the decision box 184, the damaged layer 186 is removed and a new layer 188 is provided. If no such damage or defect is detected, the process continues 190 to the next layer. The self-test program applies to all embodiments discussed herein, including embodiments using nozzles and embodiments involving paste spreading.

[0202] An inert environment may be used for the processes of any of the above embodiments, such as filling with nitrogen, argon or even in a vacuum. This may be helpful for highly oxidizing materials.

[0203] It is expected that during the patent term of this application, many related molding, three-dimensional printing, and casting technologies will be developed, and the scope of the corresponding terms is intended to include all such new technologies.

[0204] The terms "comprises", "comprising", "includes", "including", "has" and their conjugates mean "including but not limited to".

[0205] The term "consisting of" means "including and limited to".

[0206] The term "consisting essentially of" means that the composition, method or structure may include additional ingredients, steps and / or components, provided that the additional ingredients, steps and / or components do not materially alter the basic and novel characteristics of the claimed composition, method or structure.

[0207] As used herein, the singular forms "a", "an" and "the" include plural references unless the context clearly indicates otherwise.

[0208] It should be understood that certain features of the invention described in the context of separate embodiments may also be provided in combination in a single embodiment, and this specification should be understood as if such combinations were expressly set forth herein. Conversely, for the sake of brevity, the various features of the invention described in the context of a single embodiment may also be provided separately or in any suitable sub-combination or in a combination suitable for any other described embodiment of the invention, and this specification should be understood as if such combinations were expressly set forth herein. Certain features described in the context of various embodiments should not be considered essential features of those embodiments unless the embodiment cannot operate without those elements.

[0209] Although the invention has been described in connection with specific embodiments thereof, it is apparent that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, all such alternatives, modifications and variations are intended to be covered within the spirit and broad scope of the appended claims.

[0210] All publications, patents and patent applications mentioned in this specification are hereby incorporated by reference in their entirety as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated by reference. Additionally, the citation or identification of any reference in this application should not be construed as an admission that such reference is available as prior art to the present invention. To the extent that section headings are used, they should not be construed as necessarily limiting.

Claims

1. A method of manufacturing a molded layered product, characterized in that : the method comprises: performing three-dimensional printing of a first mold to provide a wall surrounding the outside of an internal space, the internal space defining a layer of the product, the internal space having a height defined by the height of the wall; filling the internal space of the three-dimensionally printed first mold with a casting material up to the height, the internal space within the wall forming the first layer of the molded layered product; hardening the first layer; finishing the upper surface of the first layer; performing three-dimensional printing of a second mold on the finished surface of the hardened first layer to provide a second wall surrounding the outside of a second internal space, the second internal space defining a second layer of the product, the second internal space having a second height defined by the height of the second wall; and covering the first layer by pouring more casting material and filling the second internal space of the three-dimensionally printed second mold up to the second height; thereby forming a second layer on top of the first layer to form a molded layered product, wherein the casting material comprises a paste containing ceramics or metals.

2. The method according to claim 1, characterized in that : a mold printing material is used to print the mold.

3. The method according to claim 2, characterized in that : the melting point of the mold printing material is lower than the melting point of the casting material.

4. The method according to claim 1, characterized in that : the paste forming the casting material comprises an element of a first group, the first group comprising wax, binder, hardening material, dispersant, defoamer, monomer, oligomer, initiator, activator, stabilizer, debinding control additive and sintering control agent.

5. The method according to claim 1, characterized in that : the viscosity of the mold printing material is higher than the viscosity of the casting material.

6. The method according to claim 1, characterized in that : the casting material comprises hydrophilic or hydrophobic components.

7. The method according to claim 1, characterized in that : the pouring is from a pouring nozzle.

8. The method according to claim 7, characterized in that : the method comprises selecting the pouring nozzle according to the dimensions of the space in the mold to be filled.

9. The method according to claim 1, characterized in that : the filling comprises injection molding of the casting material into the mold.

10. The method according to claim 1, characterized in that : the filling comprises using a squeegee to press on the mold to spread the casting material into the mold, or the filling comprises using a blade spaced from the mold surface to spread the casting material into the mold.

11. The method according to claim 1, characterized in that : the method comprises using at least two different casting materials in different layers.

12. The method according to claim 1, characterized in that : the casting material comprises at least two different constituent materials or at least two different sizes of particles.

13. The method according to claim 1, characterized in that : The method includes removing the mold after casting using one of the following methods: heating, dissolving, and a combination of heating and dissolving.

14. The method according to claim 1 above, characterized in that : when using a three-dimensional printing device to print a mold and fill the mold, the device includes: a first nozzle, having a first size, for three-dimensionally printing the mold using a first mold material; and a second nozzle, having a second size different from the first size, for pouring a material to fill the mold.

15. The method according to claim 14, characterized in that : the second nozzle is removable.

16. The method according to claim 14, characterized in that : the second nozzle is replaceable, so as to provide different filling rates for molds of different sizes.

17. The method according to claim 14, characterized in that : the first nozzle is a fused deposition modeling extruder.

18. The method according to claim 14, characterized in that : the first nozzle is an inkjet nozzle or an array of inkjet nozzles.

19. The method according to claim 1, characterized in that : when using a three-dimensional printing device to print a mold and fill the mold, the device includes: a nozzle, for three-dimensionally printing the mold using a mold material; and a squeegee, for pasting the poured filling material into the mold.

20. The method according to claim 1, characterized in that : when using a three-dimensional printing device to print a mold and fill the mold, the device includes: a nozzle, for three-dimensionally printing the mold using a mold material; a sealing cover, for sealing the mold; and an injection molding unit, for injecting a filling material to fill the mold.

21. A method for manufacturing a laminated molded product, characterized in that : the method includes: preparing a plan view of the laminated molded product; cutting the plan view into a plurality of layers; planning a mold for each layer as an outer wall surrounding the corresponding layer; for each successive layer, three-dimensionally printing the corresponding planned mold such that the corresponding mold forms the outer boundary of the layer, and the space within the boundary defines the corresponding layer; and for each successive layer, after forming the corresponding three-dimensionally printed mold, pouring a casting material into the three-dimensionally printed mold to form the corresponding layer; and three-dimensionally printing successive layer molds on respective successive layers, wherein the casting material includes a paste containing ceramics or metals.

22. The method according to claim 21, characterized in that : the method further includes hardening each layer before printing successive layer molds thereon.

23. The method according to claim 21, characterized in that : the method includes polishing each layer before forming subsequent layers on the layers.

24. The method according to claim 21, characterized in that : the casting material is selected to have rheological properties to flow and fill the mold and adhere to the inner surface of the mold.

25. The method according to claim 21, characterized in that : the method includes using heat to stabilize the product after all layers of the product have been formed.

26. The method according to claim 21, wherein : the method includes removing the corresponding mold.

27. The method according to claim 21, wherein : the method includes heating or using a solvent to remove the sacrificial material from the casting material.

28. The method according to claim 21, wherein : the casting material includes powder, and the method includes applying a heat treatment to sinter the powder.

29. The method according to claim 21, wherein : the method further includes using a hot isostatic pressing process to increase the density of the casting material.

Images