JPH08252867A - Manufacture of sintered material of powder-mixed photosetting resin molded material - Google Patents

Abstract

PURPOSE: To provide a method for manufacturing the sintered material of a powder-mixed optically molding material in which the deformation and peeling in an optically molding material or the deformation due to gravity at the time of sintering can be corrected. CONSTITUTION: Fluidized photosetting resin 30 is kneaded with inorganic powder 31 which can be sintered (32), the obtained powder-mixed photosetting resin is introduced into the tank of an optically molding machine, and a three- dimensional structure is molded by the machine (33). In the molding, the powder- mixed photosetting resin fixed at the one cured layer is irradiated with a light in a desired shape from the upper surface of the resin to form the one cured layer, and the cured layer is sequentially laminated to form a desired three- dimensional structure (33). Then the obtained resin component of the structure is burned to be removed, for example, by heating (34). The thus obtained powder-mixed molding is heated at a high temperature to be sintered (35), and then hot isotropically pressurized (36). The sintered material is further heated to be sintered under pressure in the isotropic pressurization.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to metals and their oxides,
Alternatively, a sintered body having a three-dimensional structure made of a non-metal material such as ceramics and nitride, particularly a method for producing a sintered body of a powder-mixed stereolithography body used for manufacturing a minute three-dimensional structure, and the method. It relates to the obtained sintered structure.

[0002]

2. Description of the Related Art A stereolithography method for a three-dimensional structure is performed by irradiating a fluid photocurable resin with light to form a photocurable layer, and laminating a plurality of the photocurable layers to form a desired three-dimensional structure. There is a method of manufacturing a shaped body. This modeling method has drawbacks such as weak material strength and low heat resistance because the component is a photocurable resin. Therefore, the stereolithography method using the photocurable resin was used for making a prototype model by this method to evaluate the shape of parts and for the simulation of medical treatment [(labor saving and automation, September 1992 issue, P38-63) ( Nikkei PB Publishing Center Publishing "Rapid prototyping that changes the basic production system for high-speed three-dimensional molding").

This stereolithography method comprises the steps shown in the flow chart of FIG. In this modeling method,
Input the drawing of 3D structure into 3D CAD (10
0), a horizontal slice graphic data group for each constant thickness is created for the three-dimensional structure (101). Next, a light-curable resin (an oligomer such as epoxy acrylate or urethane acrylate to which a reactive diluent or a photoinitiator is added) is introduced into a liftable elevator, and the elevator is cured to the desired light. It is moved to a fixed layer thickness position where the layer thickness is obtained and fixed (10
2), planarly irradiating a desired shape (light is a laser beam, for example, an excimer laser (308 nm) having a wavelength range of ultraviolet rays, a He-Cd laser (325 nm), A
An r laser (351 to 346 nm), an Ar laser (488 nm) or the like is used when a visible light curable resin is used. )
(103) and then the light irradiation is stopped after the desired shape is obtained. After that, the elevator is moved by a constant layer thickness to obtain a desired photocured layer thickness (104), and the above (1)
03) and (104) are performed. The above steps are repeated until the desired three-dimensional structure is obtained, and the photo-cured layer is laminated (105). Then, the uncured photocurable resin layer is washed (106), and post-exposure (107) is performed to irradiate the entire three-dimensional shaped structure with light to completely cure the entire structure.

The details of these stereolithography steps are shown in FIG. This figure is an example of the regulated liquid level method in which light is irradiated from the lower surface of the photocurable resin to form a three-dimensional structure. This regulated liquid level method is a tank provided with an elevator 6 and a light-transmitting glass (for example, quartz glass) 3 covered with a material having low wettability (for example, Teflon tape) for peeling off a cured photocurable resin. In this method, the curable resin 5 introduced in 2 is irradiated with light 4 from the bottom of the tank through the glass 3 to cure the photocurable resin. A focused laser beam 4 can be used as the light source. For example, wavelength 330-
364 nm or 488 nm Ar laser, wavelength 32
A 5 nm He-Cd laser is preferably used. The photocurable fluid resin 5 is a photocurable fluid resin that is cured by, for example, X-rays, ultraviolet rays, visible light, or the like, such as that shown in FIG.
Oligomer such as epoxy acrylate, urethane acrylate, reactive diluent (monomer),
Photopolymerization initiator (benzoin, acetophenone, etc.)
It consists of three elements. As shown in FIG. 2A, first, the elevator 6 is raised so that the distance between the elevator 6 and the glass plate 3 becomes a constant lamination thickness, and the laser beam 4 is irradiated to cure the cured product 3 of the photocurable fluid resin. To manufacture. Figure 2
-B is a diagram showing a state in which the photocurable fluid resin is cured by a predetermined first layer. FIG. 2C is a diagram in which the irradiation of the laser beam is stopped and the table 6 is raised by a predetermined interval in order to obtain the photocurable fluid resin cured product of the second layer. Figure 2
-D is a diagram in which a photocurable liquid resin cured product of the second layer is created by a laser beam. The procedure of FIGS. 2-A to D is repeated to form a three-dimensional structure while curing and stacking the photocurable fluid resin.

The details of the stereolithography process by another method are shown in FIG. This figure is a diagram showing a free liquid surface method of irradiating light from the upper surface of the photocurable fluidized resin to form a stereolithographic object. This method is a method of curing the photocurable resin by irradiating the photocurable resin 5 with ultraviolet rays 4 or the like from the upper surface direction, and the elevator 6 descends at a predetermined interval to cure the photocurable fluid resin, A three-dimensional model is formed while stacking.

Although the three-dimensional structural form can be obtained as described above, in these stereolithography methods, although a three-dimensional structure having a complicated shape can be produced at once in a continuous process, it is possible to obtain a single shape. Only a molded body made of a resin material can be manufactured, and furthermore, the optical molded body is made of only a resin material, and cannot be processed by a material having excellent mechanical strength such as metal. In addition, since it is made of only resin material, it has a problem of poor heat resistance. In order to solve such a problem, a proposal relating to mixing a metal or ceramic powder with a photocurable resin to manufacture a stereolithography object is disclosed in Japanese Laid-Open Patent Publication No. 4-9.
9203. This is the content as shown in FIG. That is, after mixing the inorganic powder material 11 into the liquid photocurable fluid resin 10 and kneading 12,
The resin is cured by irradiating this with light by the regulated liquid surface method or the free liquid surface method to manufacture a stereolithography object (1
3). After that, the resin component in the molded body is removed by burning (1
4) Further, a powder-mixed shaped body obtained by further burning and removing the resin component is sintered at a high temperature to form a structure made of metal or ceramic material, or a structure made of a mixed material of both. In addition, this method forms a powder-mixed resin laminate of a predetermined shape created by changing the compounding ratio of metal or ceramic powder for each laminate, and heats the resin molded body in a high temperature atmosphere to burn the resin component. It is a stereolithography method that can remove the powder and burn the contained powder to form a functionally gradient material having a desired shape.

However, this method has the following problems. (I) Since the structure is formed while stacking, unevenness is formed on the side surface of the stacked portion. In particular, in the case of manufacturing a fine shaped body such as a micromachine, the side surface has irregularities of several tens of microns to several microns, and a desired shaped body cannot be obtained. (Ii) In the case of stereolithography by the regulated liquid level method of FIG. 2, in the step of raising the elevator, the cured molded article is cured when it is peeled from the glass plate 3 covered with the material having low wettability. The molded product may be deformed and peeled off, and a peeled part (void) is formed between a part of the layers on the side surface of the stacked portion (FIG. 5 (21)) (FIG. 5 (22)), and the optical molded product is deformed. To do. (Iii) The stereolithography object may be cracked in the degreasing / sintering process. (IV) The material strength is weak because the sintered density is low, and in the case of materials such as PZT and PLZT which have piezoelectric characteristics,
The desired piezoelectric effect cannot be obtained due to the low sintering density. (V) For example, when a powder material such as PZT or PLZT having piezoelectric characteristics is used, the crystal of the powder material grows into grains, which makes it difficult to manufacture a sintered body having a high relative dielectric constant using a piezoelectric material. is there. (Vi) When a powder material (eg, BaTiO ₃ ) is sintered, if it is placed directly on the heat-resistant block, the components of the heat-resistant block (eg, SiO ₂ ) and the sintered body will react and melt. , Al ₂ O ₃ , Zr on heat resistant block
O ₂ powder must be spread. In particular, PZT and PLZT, which have piezoelectric properties, change their piezoelectric properties even with slight chemical changes, so it is necessary to appropriately select the powder component on the heat resistant block.

Further, there is also a problem in the case where the stereolithography body of a powder-mixed curable resin having a complicated three-dimensional structure is put into a high temperature furnace and sintered in the step of degreasing and sintering. This problem will be described with reference to FIGS. 7 and 8.
In FIG. 7, a powder-mixed resin molded body 20 having a desired three-dimensional structure, a heat-resistant dish 24 (for example, the material is silicon nitride), a heat-resistant powder 25 (this may be, for example, an alumina powder). .) Is shown, and the heat-resistant powder 25
The powder-mixed resin shaped body 20 is placed on top of the above. Further, in FIG. 8, the powder mixed resin shaped body 20 is placed on the heat resistant block 26 (for example, the material may be silicon nitride). In both cases, when the powder-mixed resin molded body 20 is placed on the heat-resistant powder 25 or the heat-resistant block 26 so as not to be partially stressed by gravity, the degreasing / sintering process is performed. Deformation occurs. In particular, it is extremely difficult to determine the direction of a complicated three-dimensional model or a fine model that is a part of a micromachine so that the direction is determined so that stress is not applied locally. Furthermore, in the degreasing and sintering process,
Shrinkage of the stereolithography object and the heat-resistant powder or heat-resistant block occurs, but since this shrinkage rate differs between the stereolithography object and the heat-resistant powder 25 or heat-resistant block 26, this shrinkage occurs. Due to the difference in the rate, stress is applied to the stereolithography object and deformation occurs. Therefore, it was extremely difficult to manufacture a highly accurate sintered body without being deformed.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to produce a desired three-dimensional model in the case of manufacturing a fine model such as a micromachine. Is to provide a method for producing a sintered body of a powder-mixed stereolithography body in which the concavo-convex shape of the side surface is reduced so that Further, it is another object of the present invention to provide a method for producing a sintered body of a powder-mixed stereolithography body which can correct the deformation of the fabrication body caused by peeling during the step of stereolithography by the regulated liquid level method.

Further, according to the present invention, the contact area between the stereolithography body and the heat-resistant block is reduced by integrally providing the supporting portion for supporting the desired stereolithography body itself, and the degreasing / sintering process is performed. Provided is a method for manufacturing a stereolithography object that can reduce deformation due to gravity.

Further, by providing the supporting portion, only the supporting portion directly contacts the heat resistant block,
Provided is a method for producing a sintered body of a powder-mixed stereolithography body, which can sinter a desired stereolithography body without causing dissolution or characteristic change due to a chemical reaction. Furthermore, the present invention provides a sinter-molded body of a powder-mixed curable resin-molded body provided with a support portion.

[0012]

The above problems can be solved by the following (A) to (C). (A) A photocurable layer is formed by irradiating a light image on a layer of a powder-mixed photocurable fluid resin in which a sinterable inorganic powder material is mixed in a photocurable fluid resin that is cured by light, and the photocured layer is formed. An optical molding step of molding a three-dimensional molded body by sequentially stacking layers, a resin removing step of removing a resin component of the powder mixed resin molded body to form a powder mixed molded body, and the powder mixed molding A method for producing a sintered body, comprising the step of heating a body into a sintered body, wherein the sintering step is performed by hot isostatic pressing or the sintering step is performed. A method for manufacturing a sintered body of a powder-mixed stereolithography body, which further comprises hot isostatic pressing.

(B) A layer of a powder-mixed photocurable fluid resin in which a sinterable inorganic powder material is mixed in a photocurable fluid resin that is cured by light is irradiated with a light image to form a photocurable layer, By sequentially stacking and forming this photo-curable layer, a stereolithography process for molding a three-dimensional molded body, a resin removal process for removing a resin component of the powder-mixed resin molded body to form a powder-mixed molded body, and A sintering step of heating the powder-mixed shaped body into a sintered body, and a sintered body manufacturing method comprising a hot isostatic pressing step, wherein the powder-mixed shaped body manufactured in the optical shaping step comprises: A molded body comprising a support portion that supports the molded body integrally molded with the powder mixed resin molded body,
The method for producing a sintered body of a powder-mixed stereolithography body, further comprising a step of removing the supporting portion after the isotropic pressure treatment step.

(C) In the method for producing a sintered body according to (B) above, a cutout having a minimum cross-sectional area is provided in the support portion of the molded body in the vicinity of the powder mixed resin molded body. A method for manufacturing a sintered body, characterized by comprising:

In the present invention, the powder-mixed photo-curable resin is a photo-curable fluid resin which is cured by light, and a sinterable inorganic material, and if necessary, a reactive diluent and a photo-curable resin. A mixture of a polymerization initiator and the like.

In the present invention, the sinterable inorganic material means metal powder, ceramic powder, fiber, whiskers and the like. Further, in the present invention, a molded article (or an optical molded article) and a sintered article are a powder mixed photocurable resin molded article obtained by photocuring a powder mixed photocurable resin,
And this sintered body, which is a shaped body (or a stereolithography body), and a sintered body does not include a support portion or a base provided on the shaped body and has a desired structure to be manufactured by the method of the present invention. It means a thing and a sintered body.

Further, in the present invention, the support portion or the base means a member provided on the molded body so as to prevent the molded article from being stressed by gravity or contraction during the sintering process.

The present invention will be described in more detail below. A first invention is a method for producing a sintered body according to the above (A).
In the present invention, the photocurable fluid resin that can be used in the present invention is not particularly limited as long as it is a photocurable fluid resin that can be cured by light, for example, X-rays, ultraviolet rays, visible light or the like. For example, acrylic resin, epoxy resin, etc. can be mentioned. Specifically, it is a monomer or oligomer having an acryloyl group, and depending on the molecular structure constituting the skeleton thereof, polyester acrylate, polyurethane acrylate, epoxy acrylate, polyether acrylate, silicon acrylate, oligo acrylate and the like can be mentioned.

In the present invention, the above photopolymerizable resins may be used alone or in combination. Examples of the polymerization initiator include dihydroxyacetophenone, acetophenone-based polymerization initiators such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzoin ether-based polymerization initiators such as isobutyl benzoin ether and isopropyl benzoin ether, and benzyl. Benzyl ketal-based polymerization initiators such as methyl ketal and 1-hydroxycyclohexyl phenyl ketone, benzophenone, 2-
Examples include ketone polymerization initiators such as chlorothioxanthone.

The fluid photocurable resin is prepared by mixing a photoinitiator with the above photopolymerizable resin, if necessary. The powder that can be used in the present invention includes fibers, whiskers,
Examples include metal powder and ceramic powder. Specifically, there are alumina, silica, stainless steel, copper, PZT (lead zirconium titanium oxide), PLZT (lead lanthanum zirconium titanium oxide), and aluminum. In the present invention, especially PZ
It is preferable to use T or PVZT. Here, as the means for powdering the inorganic material, water atomizing method or gas atomizing method, and further, for example, Koji Takahashi, Ichiro Tsuji, Saburo Nagata, application to high temperature structural member by heat resistant alloy powder injection molding, industrial material, No. 39 No., NO12, 199
There is a method for processing fine powder as described in detail in the September issue, P43-45. Furthermore, the metal alkoxide is hydrolyzed at room temperature to form a sol, and this reaction is allowed to proceed to form a gel, which is then calcined at a low temperature to obtain fibers or powders. Sol-gel method (Sakuhana S., sol-gel method) Science, Agne Jofusha Co., Ltd., 1988). The materials made into powder by these processing methods are SUS316L, SUS3
04, Fe-Co-V system (Fe49% .Co49% .V
2%), Cu-Sn alloy, Cu-Ni alloy, SiO _2,
Examples include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , and BaTiO ₃ . On the other hand, the material that transmits light may be soda glass, lead glass, Pyrex glass, epoxy, polyethylene, polypropylene or the like. The material for the whiskers is obtained by processing alumina (Al ₂ O ₃ ), potassium titanate (K ₂ O.nTiO ₂ ), graphite, polyoxymethylene and the like. Furthermore, titanium alloy (Ti-6Al-4V), cemented carbide (WC-Co type), PZT, Ni-Zn-ferrite,
Mn-Zn- ferrite, Y-PSZ (yttria partially-stabilized _{zirconia), Si 3 N 4 -Al 2} O 3 -Y 2 O
₃ , SiC or the like can be used.

The powder-mixed photocurable resin of the present invention is prepared by mixing the above-mentioned fluid photocurable resin with the above powder. The mixing ratio in volume of the fluid photocurable resin and the powder is preferably 25% to 48% with respect to the fluid photocurable resin. However, it may be out of this range depending on the photocurable resin and powder.

The first invention will be described with reference to the flow chart shown in FIG. First, a fluid photocurable resin (30) is prepared. As the fluid photocurable resin, a commercially available product can be used as it is.

The fluid photocurable resin (30) is kneaded with the inorganic powder (31) (32). The method of kneading is not particularly limited, but a stirring / defoaming machine for simultaneously performing defoaming and kneading, or
A centrifugal defoamer can be preferably used. The powder-mixed photocurable resin obtained is introduced into the tank of the stereolithography machine. For the introduction, for example, a method of pouring slowly so that air bubbles do not enter from the end of the tank can be used. It is also possible to introduce it into the tank using a syringe. The present invention is not limited to these methods, and the powder-mixed photocurable resin can be introduced by various methods. Next, a three-dimensional structure is formed by a stereolithography device (33).

An outline of stereolithography will be described. It is preferable to insert an elevator into the tank and apply vibration to the powder-mixed photocurable flow resin by means of applying vibration. This is for uniformly dispersing the powder in the fluid photocurable resin. The means for applying this vibration is not particularly limited as long as it can apply the vibration of the ultrasonic device or the like to the powder-mixed photocurable fluid resin.

Next, the elevator is moved to a predetermined position, that is, the thickness of the hardened layer. For example, in the regulated liquid level method,
From the glass surface installed on the bottom, one layer of the cured layer is fixed (see FIG. 2). Moreover, in the free liquid level method, the powder-mixed photo-curable resin is fixed to one layer of the cured layer from the upper surface (FIG. 3).
reference). After fixing the elevator, a desired shape is irradiated with light to form a cured layer for one layer. In the present invention,
Although the vibration can be applied during the light irradiation, it is preferable to stop the vibration in the light irradiation step so that the cured product is not deformed and the dimensional accuracy is not deteriorated. Even if the vibration is stopped at the stage of light irradiation, there is no particular problem because the powder does not settle immediately.

Next, the light is stopped when the resin is cured into a desired shape. The above light irradiation process is repeated until a desired three-dimensional structure is formed. Each process by the above-mentioned optical modeling machine can be advanced while performing defoaming, if necessary. Defoaming is performed by using the above-mentioned apparatus of the present invention to reduce the pressure in the tank with a vacuum pump or the like. The degree of pressure reduction in the tank is not particularly limited, but is 0.15 to 0.0
1 mmHg is preferred. Further, when defoaming, vibration is performed in at least one step of each step of shaping the three-dimensional structure, and therefore it is preferable to continuously perform the optical shaping.

After the desired shape has been shaped, the elevator is brought out of the tank. Next, the resin component of the obtained three-dimensional structure is removed. Any conventional method can be used to remove this resin. For example, there is combustion removal by heating. The temperature of this combustion removal varies somewhat depending on the material of the photocurable fluid resin, but the temperature rising rate is 5 ° C / hour to 300 ° C /
Combustion removal can be performed at a maximum temperature of 300 to 650 ° C. in time.

As another resin removal method, a photocurable fluid resin, in which the resin after photocuring is dissolved in a solution,
For example, if a water-soluble type ThreeBond 3000 series photocurable resin such as 3046 or 3046B is used, the resin component can be dissolved and removed by treating the powder-mixed resin molded body in an aqueous solution or a high humidity atmosphere. .

Next, the obtained powder mixed shaped body is sintered. Sintering may be performed by heating the powder-mixed shaped body at a high temperature. In the case of the water atomized powder of SUS316L, the heating temperature is 1300 ° C. in the air and the nitrogen atmosphere for 3 hours, and a good sintered body is formed, and the Fe—Co—V type (Fe49%, Co
49%, V2%), a desired sintered body can be manufactured by performing sintering at 1440 ° C. Further, in the case of alumina having an average particle diameter of powder of 1 μm, 1200 to 1500 ° C.
It is possible to sinter at a temperature of 1 hour or more and a sintering time of 1 hour or more.

Next, a hot isostatic pressing process is performed. In this hot isotropic heat treatment, the sintered body is further heated and sintered under high pressure. The hot isotropic heat treatment uses a high-pressure gas generator,
It is performed by a hot isotropic heat treatment device including a vacuum device, a hydraulic unit, a pressure vessel having a furnace structure, a cooling device, a heating power supply control device, a safety device, a product handling device, and the like. This device is, for example, an "isostatic press technology (HI
P ・ CIP technology and its application to material development) Nikkan Kogyo Shimbun
Those known in literature such as can be used.

Specifically, hot isotropic heat treatment is performed in a pressure vessel whose schematic view is shown in FIG. That is, the heater 30
3, a pressure vessel 300 equipped with a heat insulating material 302 and a valve 301
The sintered body 304 is placed in and the hot isotropic heat treatment is performed under a predetermined pressure and temperature. Argon or nitrogen can be used for pressurization, but argon is preferable. The apparatus shown in FIG. 10 is merely an example, and may be any pressurized container as long as it can be used in the hot isostatic pressing process.

The hot isotropic heat treatment 37 may be carried out at a pressure of 300 to 2000 Kgf / cm ² and a temperature of 350 to 1950 ° C., although the conditions vary depending on the type of powder. For example, in the case of alumina whose sintered powder has an average particle diameter of 1 μm, the pressure is 800 to 1000 kgf / cm ² , and the temperature is 1350 to 1450 ° C.
In the above, a good sintered body can be manufactured by performing hot isostatic pressing. As described above, by performing the hot isotropic pressure treatment, the grain growth of the sintered body is promoted, and at the same time, the change occurs in the state where the surface energy is in the minimum state, that is, the surface area of the grain boundary is decreased, so Particles grow so as to eliminate such gaps, and there is no peeling portion that can occur in the regulated liquid surface method.

In the present invention, the sintering step and the hot isostatic pressing treatment can be performed separately as described above, but the sintering step is performed as a hot isostatic pressing treatment under high temperature and high pressure. The sintering step may be omitted.

As described above, according to the method for producing a sintered body of the first aspect of the present invention, it is possible to provide a homogeneous shaped body having no peeling portion. Next, the second invention will be described.

In the second invention, resin removal, sintering,
The hot isotropic heat treatment is as described above in the first invention. In the first aspect of the second invention, a powder-mixed photocurable resin molded article having a support portion that supports the powder-mixed resin molded body when molding a three-dimensional molded body is created.

FIG. 11 shows a stereolithography product according to one embodiment of the second invention, and FIG. 12 is a diagram showing one embodiment for sintering the stereolithography product. The stereolithography of the first aspect,
Desired three-dimensional powder-mixed resin molded body 40 made of powder-mixed photo-curable resin, supporting portion 41 made of powder-mixed photo-curable resin supporting the molded body 40, and powder-mixed photo-curable resin in contact with only the supporting portion 41. It is composed of a table 42 consisting of. FIG. 12 shows a heat-resistant block 43 of the stereolithography object of FIG.
FIG. Degreasing / sintering /
Perform hot isostatic pressing. Normally, when a heat-resistant block is used for sintering and hot isostatic pressing, the stereolithography object shrinks, but the heat-resistant block hardly shrinks and deforms at the contact area between the stereolithography object and the heat-resistant block. Happens. However, FIG.
By providing the base 42 and the supporting portion 41 as shown in 1, the stereolithography object 40 is not directly in contact with the heat resistant block and is not affected by shrinkage, and a uniform three-dimensional sintered product with high sintering density is obtained. You can

Here, it is preferable that the support portion 41 that supports the stereolithography object 40 on the table 42 is provided so that the stereolithography object 40 is not distorted by gravity. Select as appropriate. In addition, the support portion 41
The length and width are not particularly limited, but they are set so that the stereolithography object 40 can be efficiently supported and that the support portion 41 and the base 42 can be easily removed in a later step.

Further, in the case of a complicated three-dimensional structure, if it is not placed on the block 43 so that partial stress is not applied by gravity, deformation such as crushing will occur in the degreasing / sintering process. When dimensional accuracy of several to several tens of microns is required for a fine structure that is a part of a micromachine, etc., the orientation should be such that the fine stereolithography object is not partially stressed when placed on a block. However, this is extremely difficult as a problem. However, as shown in FIG. 11, the support portion 41 for supporting the desired three-dimensional powder-mixed resin molded body 40 is provided integrally with the powder-mixed resin molded body 40. Stress can be reduced, and deformation during sintering and hot isostatic pressing is reduced. Further, since the powder-mixed resin molded body 40 and the supporting portion 41 can be made of the same material, the supporting portion 41 that supports the contraction during degreasing / sintering / hot isostatic pressing is powder. As the mixed resin molded body 40 contracts at the same ratio, the powder mixed resin molded body 40 can be prevented from being affected by the contraction and can be prevented from being deformed.

Next, the obtained sintered product is processed into a desired sintered body. This step will be described with reference to FIG. FIG. 13 is a series of diagrams in which the base 42 and the support portion 41 are removed from the modeled product that has become a sintered product. First, the support portion is cut by applying a partial stress (A to B). Next, the cut portion of the slightly remaining supporting portion is polished to obtain a desired sintered body. By removing the unnecessary supporting portions in this way, it is possible to obtain a sintered body with little deformation. Naturally, various modifications and changes can be made to this aspect.

For example, sintering / hot isostatic pressing can be performed by using a stereolithography object having only a supporting portion 41 that supports the bottom surface of a desired three-dimensional structure. Even in such a mode, the same effect as the above can be obtained. Further, since the base 42 is not provided, the time for stereolithography can be shortened.

Here, it is preferable that the supporting portions 41 are provided so that the stereolithography body 40 is not distorted by gravity, and the number thereof is appropriately selected according to the stereolithography body 40. The length and width of the support portion 41 are not particularly limited, but they are set so that the stereolithography object 40 can be efficiently supported and that the support portion 41 can be easily removed in a later step.

In the second aspect of the second invention, as shown in FIG. 14, a desired three-dimensional powder-mixed resin molded body 51 made of powder-mixed photo-curable resin and powder-mixed photo-curing for supporting the molded body 51. A stereolithographic object is used which is composed of a support portion 50 made of a resin and a rod-shaped body 52 made of a powder-mixed photocurable resin connected to the support portion 50. Here, it is preferable that the supporting portion is provided at the center of the stereolithography body 51 so that an excessive stress is not applied to the stereolithography body 51. Further, the length and width of the support portion 50 are not particularly limited, but the stereolithography object 5
1 can be efficiently supported, and the rod-shaped body 52 can be easily removed in a later step. For example, the powder-mixed resin molding 51 is a powder-mixed resin molding made of a powder-mixed photocurable resin in which an alumina powder material having an average particle diameter of 1 micron is mixed with a UV bond resin 3042 manufactured by ThreeBond at a volume ratio of 30:60. When a sample with a body weight of 3.5 mmg is formed and further subjected to degreasing / sintering / hot isostatic pressing, the cross-sectional area of the supporting part 50 is 0.5 × 0.5 mm and the supporting part 50 is It has been found that sintering can be performed at one place. Further, the rod-shaped body may have a rectangular parallelepiped shape or a cylindrical shape as long as it can be properly placed on the heat resistant block. FIG.
[Fig. 3] is a diagram showing a stereolithographic object placed on the heat-resistant block 53, and is placed in a furnace with such a configuration. The feature is that the optical molding 51 is hung from the upper surface, which is effective in the case of a structure in which the support portion cannot be molded on the lower surface. In particular, since the support portion 50 receives a force in the direction of gravity, it is not deformed by being crushed. This is especially effective when the weight is small and is a microstructure such as a part of a micromachine.

Then, as shown in FIG. 16, unnecessary portions of the sintered product obtained in the second aspect of the second invention are removed.
Since there is only one support portion 50, the removal work is easy. Naturally, various modifications and changes can be made to this aspect.

For example, since the molded article has the rod-shaped body 52, the supporting section may be a supporting section that supports the powder-mixed resin molded body 51. Therefore, the support is hook-shaped,
It may have a key shape, a ring shape, a U shape, a spherical shape, or may be shaped into a hanging table.

Further, it is possible to form a plurality of desired three-dimensional stereolithography objects on one rod-shaped object 52. Further, as another modified example, a stereolithography object as shown in FIG. 17 can be cited. This stereolithography product is a desired three-dimensional powder-mixed resin molded body 70 made of a powder-mixed photocurable resin, and a supporting portion 71 made of a powder-mixed photocurable resin that supports the molded body 70.
It consists of With this configuration, the support portion 71
Can be molded together with the optical molding 70, and a desired three-dimensional powder-mixed resin molded product can be molded in a short time. Here, the supporting portion 71 may have a rectangular parallelepiped shape or a cylindrical shape as long as it can be properly installed on the heat resistant block. Further, in this mode, as shown in FIG. 18, the modeled object is placed on the heat resistant block 72. This is subjected to the above-mentioned sintering and hot isostatic pressing. Next, the support portion 71
Is applied to remove the supporting portion 71 from the obtained sintered product (FIG. 19).

As a further mode, the mode shown in FIG. 24 can be adopted. This stereolithography product is a stereolithography product formed by combining the stereolithography products having the rod-shaped body shown in FIG. 21, and a grid 81, and a support portion for connecting the grid and a desired three-dimensional powder-mixed resin molding 80. 82 and a powder-mixed resin molded body 80. By forming the rod-shaped body into a lattice, more shaped bodies can be formed. Further, by providing a plurality of stereolithography bodies (for example, 62) each having a supporting portion on a rod-shaped body and further forming the rod-shaped body into a lattice shape or by stacking a plurality of these three-dimensionally to form a three-dimensional shape, more powder mixture can be obtained. A resin molding can be molded. In particular, the support portion can be designed according to the temperature distribution state in the furnace due to the shape of the furnace, which is efficient.

Further, in the case of forming a stereolithography object having a plurality of stereolithography objects, a desired three-dimensional powder-mixed resin molding object can be designed not only by one kind but also by another kind, which is necessary. By molding only different types and shapes integrally with the support part, it becomes easier to manage parts, and problems such as overproduction of sintered parts and lack of sintered parts are eliminated.

Further, by designing only the combination of the support portion and the various types of powder-mixed resin shaped bodies by CAD, mass production or multi-product production can be supported. Further, by designing only the combination of the support portion and the various types of powder-mixed resin shaped bodies with CAD, mass production or multi-product production can be achieved.

By using the method for producing a sintered body of a stereolithography body according to the second aspect of the invention, a homogeneous sintered body without deformation can be obtained. Next, the third invention will be described.

The third invention corresponds to the above (C). In the third invention, the resin removal, the sintering, and the hot isostatic heat treatment are as described in the first invention.

In the first aspect of the third invention,
When the powder-mixed resin molded article is molded in the optical molding step, a notch 74 is provided as shown in FIG. 20 for facilitating cutting of the supporting portion 71 from the desired three-dimensional powder-mixed resin molded article. The notch 74 is provided so as to have a minimum cross-sectional area with respect to a plane that includes aa ′ of the support portion 71 (see FIG. 20) and is parallel to the side surface of the stereolithography body 70. Notch 7
4 is for easy polishing after removing the supporting portion 71,
It is preferably provided in the vicinity of the stereolithography 70. In addition, the notch 74 may be provided on any of the upper surface, the side surface, and the lower surface of the supporting portion 71 in accordance with the desired shape of the three-dimensional powder-mixed resin molded body, and the notch 74 need not be located at one place. A plurality of them may be provided.

As still another aspect, such a notch can be provided in the first and second aspects of the second invention. By providing such a notch, the support portion 71 can be removed by applying a slight stress.

The third aspect of the present invention can be further modified. For example, in the hanging type stereolithography (see FIG. 4), when the support portion 63 is cut off by the notch 64 as shown in FIG. 21, the remaining portion of the support portion does not protrude after the cutout. A recess 64 can be provided.

With this structure, as shown in FIG. 22, after the support portion 71 is stressed to cut off the support portion 71 from the stereolithographic object, the remaining portion 65 of the support portion must be removed by polishing. , Which facilitates the production of a sintered body.

Since this concave portion is provided to prevent the excised portion from protruding, it is preferable that the concave portion be as small as possible. Such a recess can also be provided in the first aspect of the third invention described above (see FIG. 20).

Further, according to the third invention, it is possible to form a plurality of desired three-dimensional stereolithography bodies 62 on one rod-shaped body 60 (FIGS. 23 and 24). Furthermore, the third invention can be modified as shown in FIG. That is, a three-dimensional powder-mixed resin molded article 110 made of a powder-mixed photo-curable resin, and a stereolithography object having a support portion 111 made of a powder-mixed photo-curable resin that supports the molded article 110. It is possible to provide a modeled article having a structure in which the portions 111 have slightly different sizes. Such a support 1
11 can prevent the deformation in the stereolithography process. Also in this aspect, it is of course possible to provide the above-mentioned notch and recess. By using the method for producing a sintered body of the stereolithography object according to the third aspect of the invention, a uniform sintered body without deformation can be obtained.

[0057]

The light-curable powder-mixed photo-curable resin obtained by mixing the sinterable inorganic powder material in the photo-curable liquid-curable resin that is cured by light is irradiated with light while scanning the light to form a photo-curable layer. A plurality of cured layers are stacked to form a three-dimensional shaped body, the resin component of the obtained powder-mixed resin shaped body is removed, and the powder-mixed shaped body is heated to form a sintered body. Then, hot isostatic pressing is carried out to obtain a powder-mixed stereolithography body. In this case, the step of heating the powder-mixed shaped body to form a sintered body may be performed as hot isostatic pressing. By carrying out the hot isostatic pressing treatment, a homogeneous sintered body without deformation can be obtained.

Further, in the method for obtaining a sintered body of the powder-mixed stereolithography body, a supporting portion is provided on the obtained three-dimensional molding body, whereby a uniform sintered body without deformation is obtained. Furthermore, by providing a predetermined notch in the above support,
Provided is a method for producing a sintered body of a powder-mixed photocurable resin molded body, which can obtain a uniform sintered body without deformation and can easily remove the supporting portion.

[0059]

【Example】

Example 1 FIG. 9 shows a manufacturing flowchart of a method for manufacturing a sintered body of a powder-mixed stereolithography structure of the present invention. First, photocurable fluid resin 3
0 and the inorganic powder material 31 are prepared. The inorganic powder material may have a fiber shape or whiskers. The photocurable fluid resin is a photocurable fluid resin that is cured by light, such as X-rays, ultraviolet rays, or visible light, for example, an oligomer (photocurable resin such as epoxy acrylate or urethane acrylate), a reactive diluent (monomer), A resin composed of three elements of a photopolymerization initiator (a photoinitiator such as a benzoin type or an acetophenone type) is prepared. Further, as the inorganic material, a water atomizing method or a gas atomizing method, for example, Koji Takahashi, Ichiro Tsuji, Saburo Nagata, application to high temperature structural member by heat resistant alloy powder injection molding, industrial material, No. 39,
No. 12, September 1991, P43 to 45, powders processed by a method for processing fine powders are used. Also, as a method for processing powders and fibers, a sol-gel method (preparation) in which a metal alkoxide is hydrolyzed at room temperature to form a sol, and this reaction is allowed to proceed to gel and then fired at a low temperature to obtain fibers or powders The powder obtained by Hanao S., Science of Sol-Gel Method, Agne Chengfu Co., Ltd., 1988) may be used. Examples of the material made into powder by these processing methods include SUS316L and SUS30.
4, Fe-Co-V system (Fe49% .Co49% .V2
%), Cu-Sn alloy, Cu-Ni alloy, SiO _2, T
Examples include iO ₂ , ZrO ₂ , Al ₂ O ₃ , and BaTiO ₃ . On the other hand, the material that transmits light may be soda glass, lead glass, Pyrex glass, epoxy, polyethylene, polypropylene or the like. As the whiskers, alumina (Al ₂ O ₃ ) and potassium titanate (K
₂ O · nTiO ₂ ), graphite, polyoxymethylene, etc. may be processed. In the kneading step, one kind or several kinds of inorganic powder materials are kneaded with such a powder using a pressure kneader or the like. afterwards,
Defoaming is performed by a vacuum pump or the like, or kneading and defoaming are simultaneously performed by a stirring type vacuum defoaming device or the like capable of controlling temperature to produce a powder-mixed photocurable fluid resin.

Next, stereolithography of the powder-mixed photocurable fluid resin is performed. For example, in the regulated liquid level method, vibration is applied to the powder-mixed photo-curable resin by inserting an elevator into the tank and applying vibration, and then the elevator is moved to a predetermined position, that is, from the glass surface installed on the bottom surface to one cured layer. Fix to minutes (see Figure 2). After fixing the elevator, a desired shape is irradiated with light to form a cured layer for one layer. Further, the light is stopped when the resin is cured into a desired shape. The above light irradiation process is repeated until a desired three-dimensional structure is formed.
This stereolithography process can be carried out while degassing, if necessary. After the desired shape has been shaped, the elevator is brought out of the tank.

Next, the resin component of the obtained three-dimensional structure is removed. Any conventional method can be used to remove this resin. For example, combustion removal by heating can be used. In this case, the temperature of combustion removal is slightly different depending on the material of the photocurable fluid resin, but the maximum temperature is 300 to 650 at a temperature rising rate of 5 ° C / hour to 300 ° C / hour. Burn-off can be performed at ° C.

As another resin removal method, a photocurable fluid resin, in which the resin after photocuring is dissolved in a solution,
For example, if a water-soluble type ThreeBond 3000 series photocurable resin such as 3046 or 3046B is used, the resin component can be dissolved and removed by treating the powder-mixed resin molded body in an aqueous solution or a high humidity atmosphere. .

Next, in the sintering step, the powder-mixed shaped body is heated to a high temperature. In the case of the water atomized powder of SUS316L, the heating temperature is 1300 ° C. for 3 hours in the air and the nitrogen atmosphere, and a good sintered body is formed, and the Fe—Co—V system (Fe4
9%, Co49%, V2%), a desired sintered body could be manufactured by performing sintering at 1440 ° C. Further, in the case of alumina having an average particle diameter of powder of 1 μm, 1200 to
A good sintered body could be obtained at a temperature of 1500 ° C. for a sintering time of 1 hour or more.

Next, a hot isostatic pressing process is performed. In this hot isotropic heat treatment, the sintered body is further heated and sintered under high pressure. The hot isotropic heat treatment uses a high-pressure gas generator,
It is performed by a hot isotropic heat treatment device including a vacuum device, a hydraulic unit, a pressure vessel having a furnace structure, a cooling device, a heating power supply control device, a safety device, a product handling device, and the like. This device can be used, for example, in "isotropic pressure technology (HP
I / CIP technology and application to material development) Nikkan Kogyo Shimbun "
Those known in literature such as can be used.

Specifically, hot isotropic heat treatment is performed in the pressure vessel whose schematic diagram is shown in FIG. That is, the sintered body is placed in a pressure vessel 16 equipped with a heating device, a heat insulating layer, and a valve device,
Hot isotropic heat treatment is performed under a predetermined pressure and temperature. Argon or nitrogen can be used for pressurization, but argon is preferable. In this embodiment, any furnace may be used as long as it can be used in the hot isostatic pressing process.

The hot isotropic heat treatment 37 can be carried out at a pressure of 300 to 2000 Kgf / cm ² and a temperature of 350 to 1950 ° C., although the conditions vary depending on the type of powder. For example, in the case of alumina having an average particle diameter of sintered powder of 1 μm, the pressure is 8
A good sintered body could be manufactured by performing hot isostatic pressing at a temperature of 1350 to 1450 ° C. at a temperature of 0 to 1000 Kgf / cm ² .

[0067]

[Table 1]

FIG. 5 shows a sintered body manufactured by the regulated liquid level method shown in FIG. 2 and not subjected to hot isostatic pressing. Sintered body 200 not subjected to hot isostatic pressing
Then, the uneven side surface portion 21 and the peeling portion 22 which is a void generated by peeling of the layer were formed.
In this way, in the method of forming a three-dimensional powder-mixed resin molded body while forming layers by the regulated liquid level method, in order to cure the second layer of photocurable resin, the laser beam irradiation is stopped and the elevator 6 is stopped. Although the distance is increased by a certain distance, the outer periphery of the cured product may be deformed during this peeling due to the deformation of the material with low wettability attached to the glass plate 3, and the photocured product may be laminated while being deformed. A peeled portion 22 was formed, and a good sintered body could not be obtained.

On the other hand, it was found that a good sintered body can be obtained by carrying out the hot isostatic pressing treatment. FIG. 6 shows a sintered body that has been subjected to hot isostatic pressing. The sintered body 210 that has been subjected to hot isostatic pressing is sintered with the peeled portion corrected.
In this phenomenon, grain growth is accelerated by hot isostatic pressing,
A change occurs in a direction in which the minimum state of surface energy, that is, the surface area of grain boundaries is reduced. As a result, the grain boundary grows in the direction that eliminates the minute gaps, so that there is no peeling portion. In the present example, the peeled portion of the sintered body which was not subjected to the hot isostatic pressing treatment was at five places, but the peeled portion was corrected and peeled off in the sintered body which was subjected to the hot isostatic pressing treatment. No part was observed.

Further, the step due to the unevenness on the laminated side surface peculiar to the modeled body by the optical molding is also a minute gap, and the clearance generated by the steppedness due to the concavo-convex shape is also formed by degreasing, sintering and hot isostatic pressing. It is reduced by shrinking and grain boundaries growing in the direction of reducing the gap by hot isostatic pressing.

Naturally, each structure of this embodiment can be modified and changed in various ways. For example, in the hot isostatic pressing furnace, the sintering process and the hot isostatic pressing processing can be performed in one furnace by controlling the temperature setting conditions by program control. Further, when the resin removing step by heat is performed, the resin removing step by burning removal, the sintering step and the hot isostatic pressing step may be performed in one furnace if there is no adverse effect on the furnace due to the evaporated resin. it can.

Furthermore, by performing the resin removing step and the sintering step under pressure and at a high temperature, it is possible to perform the step after the resin removing step as a hot isostatic pressing process in one step. Example 2 FIGS. 11 to 13 show a sintered body manufacturing method and a sintered body of the powder-mixed stereolithography model of the present invention.

The resin removing step, the sintering step, and the hot isostatic pressing in this embodiment are the same as those in the first embodiment. Further, the same applies to the stereolithography process, but the stereolithography body obtained in the process is variously modified.

FIG. 11 shows the stereolithography product of this embodiment, and FIG. 12 shows one embodiment of sintering the stereolithography product. The stereolithography product of this embodiment includes a desired three-dimensional powder-mixed resin molded body 40 made of a powder-mixed photocurable resin, a support portion 41 made of a powder-mixed photocurable resin that supports the molded body 40, and the support portion 41. Only the powder-mixed photo-curable resin 42 is in contact with the base 42. FIG. 12 is a diagram in which the stereolithography object of FIG. 11 is placed on the heat resistant block 43. In such a state, degreasing, sintering, and hot isostatic pressing were performed. When a heat-resistant block is used for sintering and hot isostatic pressing, the stereolithography object shrinks, but the heat-resistant block does not shrink as much as the stereolithography object, and the contact area between the stereolithography object and the heat-resistant block does not. Although the deformation occurs, by providing the forty-second part and the supporting part 41 as shown in FIG. 11, the stereolithography object 40 is not directly in contact with the heat-resistant block, so that it is not affected by shrinkage, and is three-dimensional with uniform and high sintering density. A sintered body could be obtained.

Further, in the case of a complicated three-dimensional structure (not shown), unless it is placed on the block 43 so as not to be partially stressed by gravity, it may be crushed in the degreasing / sintering process. If deformation occurs, and if a dimensional accuracy of several to several tens of microns is required for a fine structure that will be a part of a micromachine, etc., the fine stereolithography object should be partially removed when it is placed on the block. It is necessary to set the orientation so that it is not stressed, but this is extremely difficult. However, as shown in FIG. 11, the support portion 41 for supporting the desired three-dimensional powder-mixed resin molded body 40 is provided integrally with the powder-mixed resin molded body 40. Stress can be reduced, and deformation during sintering and hot isostatic pressing is reduced. Further, since the stereolithography body and the support portion can be made of the same material, the proportion of the support portion supporting the shrinkage during degreasing / sintering / hot isostatic pressing is the same as that of the stereolithography body. As a result, it was possible to prevent the deformation without being affected by the shrinkage of the stereolithography body.

Next, the obtained sintered product was processed into a desired shaped body. This step will be described with reference to FIG. FIG. 13 is a series of diagrams for removing the base 42 and the support portion 41 from the sintered product. First, the supporting portion was cut by applying a partial stress (A to B). Next, the cut portion of the supporting portion, which was slightly left, was polished to obtain a molded article having a desired structure. By removing the unnecessary supporting portions in this way, it was possible to obtain a sintered shaped body with little deformation.

For example, sintering / hot isostatic pressing can be performed using a stereolithography object having only a supporting portion 41 that supports the bottom surface of a desired three-dimensional structure. Even in such a mode, the same effect as the above can be obtained. Further, since the table 42 is not provided, the modeling time can be shortened.

Here, it is preferable that the support portion 41 is provided so that the stereolithography body 40 is not strained by gravity. In the present embodiment, as shown in FIG. 11, the support portions are provided at the four corners of the stereolithography body, respectively, but the number can be appropriately selected according to the stereolithography body. In addition, the support portion 41
The length and the width of are not particularly limited, but they are set so that the stereolithographic object 40 can be efficiently supported and the supporting portion 41 can be easily removed in a later step.

Example 3 FIGS. 14 to 16 show a method for producing a sintered body of a powder-mixed stereolithographic molding product according to the present invention and a sintered product.

The resin removing step, the sintering step, and the hot isostatic pressing process of this embodiment are the same as those of the above-mentioned first embodiment. Further, the same applies to the stereolithography process, but the stereolithography body obtained in the process is variously modified.

In this embodiment, as shown in FIG. 14, a desired three-dimensional powder-mixed resin shaped body 51 made of a powder-mixed photocurable resin and a supporting portion 50 made of a powder-mixed photocurable resin for supporting the shaped body 51 are used. A stereolithographic object including a rod-shaped body 52 made of a powder-mixed photocurable resin connected to the supporting portion 50 was used. Here, the supporting portion is provided at the center of the stereolithography body 51 so that an excessive stress is not applied to the stereolithography body 51. Further, the length and width of the support portion 50 are not particularly limited, but the stereolithography body 51 can be efficiently supported,
Further, it may be set so that the rod-shaped body 52 can be easily removed in a later step. For example, the powder-mixed resin molding 51 is a powder-mixed resin molding made of a powder-mixed photocurable resin in which an alumina powder material having an average particle diameter of 1 micron is mixed with a UV bond resin 3042 manufactured by ThreeBond at a volume ratio of 30:60. When a sample with a weight of 3.5 mg was formed, and degreasing, sintering, and hot isostatic pressing were performed, the cross-sectional area of the support 50 was 0.5.
With 0.5 mm, the supporting part 50 could be sintered even at one place. Further, the rod-shaped body may have a rectangular parallelepiped shape or a cylindrical shape as long as it can be properly placed on the heat resistant block. FIG. 15 is a diagram in which the stereolithography object 5 is placed on the heat resistant block 53, and is put in the furnace with such a configuration. As a feature, since the stereolithography object 51 is hung from the upper surface,
This is effective in the case of a structure in which the support portion cannot be formed on the lower surface.
In particular, since the support portion 50 receives a force in the direction of gravity, it is not deformed by being crushed. This is especially effective when the weight is small and is a microstructure such as a part of a micromachine.

Then, as shown in FIG. 16, unnecessary portions of the sintered product obtained in this example were removed. 1 support part 50
Since it is a part, the removal work is easy. The embodiment can of course be modified or changed in various ways.

For example, since the molded article has the rod-shaped body 52, the supporting section may be a supporting section that supports the powder-mixed resin molded body 51. Therefore, the supporting portion may have a hook shape, a key shape, a ring shape, a U shape, a spherical shape, or may be formed into a hanging table shape.

Further, it is possible to form a plurality of desired three-dimensional stereolithography objects on one rod-shaped object 52. Further, as another modified example, a stereolithography object as shown in FIG. 17 can be cited. This stereolithography product is a desired three-dimensional powder-mixed resin molded body 70 made of a powder-mixed photocurable resin, and a supporting portion 71 made of a powder-mixed photocurable resin that supports the molded body 70.
It consists of With this configuration, the support portion 71
Can be molded together with the optical molding 70, and a desired three-dimensional powder-mixed resin molded product can be molded in a short time. Here, the supporting portion 71 may have a rectangular parallelepiped shape or a cylindrical shape as long as it can be properly installed on the heat resistant block. Further, in this embodiment, as shown in FIG. 18, the molded article is placed on the heat resistant block 72 and subjected to the sintering / hot isostatic pressing treatment as shown in the first embodiment. Next, stress is applied to the supporting portion 71, and the supporting portion 71 is removed from the obtained sintered product (FIG. 19).

By using the method for producing a sintered body of a stereolithography body according to this embodiment, a homogeneous sintered body without deformation can be obtained. Example 4 FIGS. 21 and 22 show a method for producing a sintered body of a powder-mixed resin shaped body of the present invention.

Also in this embodiment, the resin removing step, the sintering step and the hot isostatic pressing treatment are the same as those in the above-mentioned embodiment 1. Further, the same applies to the stereolithography process, but the stereolithography body obtained in the process is variously modified.

FIG. 21 shows a desired three-dimensional powder-mixed resin molded body 62 made of a powder-mixed photocurable resin, and the molded body 62.
3 shows a shaped body provided with a support portion 61 made of a powder-mixed photo-curable resin that supports the above. The support portion 61 is provided with a notch 63 for facilitating the excision of the support portion, and a recess 64 for preventing the excised portion from protruding after the support portion 61 is excised. Since this recess is provided to prevent the excised part from protruding, it is preferable that the recess be as small as possible. Figure 2
2 is a diagram in which stress is applied to the support 61 from the sinter to cut it off. By constructing as in this embodiment, it is possible to change the support 6 from the sintered product of the powder-mixed resin molding by simply applying stress to the support.
1 and the rod-shaped body 60 can be easily cut, and it is not necessary to polish the protruding portion 65 after cutting.

It should be noted that this embodiment is, of course, various modifications,
It can be changed. For example, as shown in FIG. 20, a desired three-dimensional powder-mixed resin molded body 70 made of a powder-mixed photocurable resin, a supporting portion 71 made of a powder-mixed photocurable resin for supporting the molded body 70, and a notch 74 are provided. It can be a stereolithography object. With such a configuration, it becomes possible to easily cut off the supporting portion 71 from the sintered body of the powder-mixed resin molded product simply by applying stress to the supporting portion.

In FIG. 20, the concave portion is not provided, but in FIG.
It is also possible to provide a concave portion around the support portion as described above. The support portion of this embodiment may be provided on any of the upper surface, side surface, and lower surface according to the desired shape of the three-dimensional powder-mixed resin molded body 62 or 70 (in this case, the shape of the support portion is powder-mixed during sintering). It is appropriately selected so that the stereolithography object can be suitably installed on the heat-resistant block.) Also, a plurality of combinations can be formed.

Furthermore, the present embodiment may have a structure not having the cutout 74 of the modification shown in FIG. An example of this is shown in FIGS. FIG. 17 shows an optical molding, which includes a desired three-dimensional powder-mixed resin molded body 70 made of a powder-mixed photocurable resin and a support portion 71 made of a powder-mixed photocurable resin for supporting the molded body 70. It is configured. FIG. 17 is a diagram showing the heat-resistant block 72 on which the stereolithographic object of FIG. 17 is placed, and the same effect as that of the second embodiment can be obtained by placing it in the furnace with such a configuration.

FIG. 19 is a view in which the supporting portion 71 of the sintered product obtained by sintering is partially stressed and cut. The remaining portion 73 after removing the supporting portion 71 is polished to obtain a desired sintered body.

Further, as described in Example 1, in order to form an optical molding, the powder-mixed curable resin is cured in a two-dimensional plane to form a thin film-shaped cured layer, and a plurality of layers are stacked. , Modeling the desired three-dimensional model. Therefore, FIG.
When obtaining a stereolithography object having a structure like the one described above, it is sufficient to perform sculpting so that a part of the sculpture is on the same plane as the two-dimensional plane for creating the stereolithography body. It is not necessary to stack a plurality of hardened layers just to create the.
Therefore, the number of times the elevator of the stereolithography machine is moved is reduced, and the molding time of the powder-mixed resin molding can be shortened.

Naturally, various modifications and changes can be made to the respective structures of this embodiment. For example, the same recesses or cutouts as described above can be formed in the stereolithography process.

An example of this modification is the stereolithographic product shown in FIG. The stereolithography product is a stereolithography product having a desired three-dimensional powder-mixed resin molding 110 made of a powder-mixed photocurable resin and a support portion 111 made of a powder-mixed photocurable resin that supports the molding 110. Thus, the support part 111 has a structure in which the sizes are slightly different from each other. Such a support part 111 can prevent deformation in the stereolithography process. In this embodiment as well, it is of course possible to provide the above-mentioned cutouts and recesses.

Example 5 FIG. 2 shows a method for producing a sintered body of a powder-mixed resin shaped body of this example.
It is shown with reference to FIG. The resin removing step, the sintering step, and the hot isostatic pressing in this example are the same as those in Example 1.
Further, the same applies to the stereolithography process, but the stereolithography body obtained in the process is variously modified.

FIG. 23 shows the shape of an optical molding. A desired three-dimensional powder-mixed resin molded body 80 made of a powder-mixed photo-curable resin, a support portion 81 made of a powder-mixed photo-curable resin for supporting the molded body 80, and a rod-shaped body 82. As shown in the figure, since a plurality of stereolithography objects 80 are formed on one rod-shaped body 82, a sintered product of a plurality of stereolithography objects can be obtained by one-time sintering and hot isostatic pressing. . In the past, it was a difficult task to arrange fine parts in a certain direction and put them in a furnace.However, a plurality of desired three-dimensional powder-mixed resin moldings are fixed to each other by a supporting part. Since the structure is large and easy to handle, a plurality of desired three-dimensional powder-mixed resin shaped bodies 80 are oriented in a fixed direction, which makes it easy for an operator to handle.

Naturally, each structure of this embodiment can be variously modified and changed. For example, as a modification, the mode shown in FIG. 24 can be adopted. This stereolithography product is a lattice 81 formed by combining the stereolithography products having the rod-shaped bodies shown in FIG. 21 to form a lattice, a support portion 82 connecting the lattice and a desired three-dimensional powder-mixed resin molding 80, and a powder. It is composed of a mixed resin molded body 80. By forming the rod-shaped body into a lattice, more shaped bodies can be formed. Further, by providing a plurality of stereolithography bodies (for example, 62) each having a supporting portion on a rod-shaped body and further forming the rod-shaped body into a lattice shape or by stacking a plurality of these three-dimensionally to form a three-dimensional shape, more powder mixture can be obtained. A resin molding can be molded. In particular, the support portion can be designed according to the temperature distribution state in the furnace due to the shape of the furnace, which is efficient.

Further, in the case of forming a stereolithography object having a plurality of stereolithography objects, a desired three-dimensional powder-mixed resin molding object can be designed not only by one kind but also by another kind. By molding only different types and shapes integrally with the support part, it becomes easier to manage parts, and problems such as overproduction of sintered parts and lack of sintered parts are eliminated.

Further, by designing only the combination of the support part and the various types of powder-mixed resin molded bodies by CAD, there is an effect that both mass production and multi-product production can be supported. Further, in the present embodiment, the support portion is not provided with a notch,
Also, it is possible to adopt a mode in which no recess is provided around the support portion.

The present invention may include inventions other than those described in (A) to (C) above. These are described below.
In addition, the above (A) to (C) are respectively the following (1),
It corresponds to (4) and (9).

(1) A layer of a powder-mixed photocurable fluid resin obtained by mixing a sinterable inorganic powder material into a photocurable fluid resin that is cured by light is irradiated with an optical image to form a photocurable layer, By sequentially stacking and forming this photo-curable layer, a stereolithography process for molding a three-dimensional molded body, a resin removal process for removing a resin component of the powder-mixed resin molded body to form a powder-mixed molded body, and A method for producing a sintered body, comprising the step of heating a powder-mixed shaped body to form a sintered body, wherein the sintering step is performed by hot isostatic pressing or the sintering step. The method for producing a sintered body for powder-mixed stereolithography, further comprising hot isostatic pressing after the above step. (Example) Example 1 is applicable. (Operation / Effect) The unevenness on the laminated side surface peculiar to the structure due to the stereolithography promotes the grain growth more by performing the hot isostatic pressing treatment than the sintering performed under the normal pressure. In this case, the change occurs in the state where the surface energy is at the minimum state, that is, the surface area of the grain boundary is reduced. Therefore, the grain boundaries grow in the direction of eliminating the minute gaps, so that the effect of reducing the minute gaps of the uneven steps of the laminated surface is further increased. Therefore, the minute gaps between the uneven surface of the laminated surface are reduced by the growth promotion of the grain boundaries of the powder. Furthermore, by performing hot isostatic pressing, the overall shrinkage is larger than that of sintering performed at normal pressure, and the unevenness of the unevenness on the stacking side surface that is peculiar to the structure that occurs during stereolithography is further reduced. You can

(2) In the method for producing a sintered body according to (1) above, powder mixing characterized in that the hot isostatic pressing treatment is performed after the sintering step is performed under normal pressure. A method for manufacturing a sintered body of a stereolithography structure. (Example) Example 1 is applicable. (Operation / Effect) Usually, when performing hot isostatic pressing, a pressure difference is generated by using a capsule made of a material such as glass to generate a pressure difference, but for a fine three-dimensional structure Glass capsules are difficult to manufacture. Therefore, since the pressure difference can be generated without using a capsule by uniformly sintering only the outer peripheral portion of the powder-mixed shaped body after the sintering step, it is possible to reduce voids inside the sintered body. It has an effect. Especially when a hot and isotropic pressure treatment is applied to a fine and complicated three-dimensional model, it is considerably difficult to manufacture a capsule for the fine and complicated three-dimensional model, but the outer peripheral part is not produced during the sintering process. Since the same effect as the capsule can be obtained only by uniformly sintering, there is an effect that it is not necessary to manufacture the capsule. Furthermore, the above (1)
Similarly to the above, it is possible to reduce the unevenness of the unevenness on the side surface of the laminate, which is peculiar to the three-dimensional object formed by stereolithography.

(3) In the method for producing a sintered body according to the above (1), sintering of a powder-mixed stereolithography body characterized in that the stereolithography step is stereolithography by a regulated liquid surface method. Body manufacturing method. (Example) Example 1 is applicable. (Operation / Effect) When stereolithography is performed by the regulated liquid level method, photocuring, peeling from the glass plate, and lamination are repeated to stereo-mold a three-dimensional powder-mixed resin cured product, but peeling from the glass plate There is a peculiar problem that the peeled portion generated in the process is easily generated on the side surface of the structure. However, by performing the hot isostatic pressing treatment, the grain growth is promoted by the sintering performed without applying the pressure, so that the minimum state of the surface energy, that is, the change of reducing the surface area of the grain boundary occurs. Therefore, the grain boundary grows in the direction of eliminating the minute gap, so that the peeled portion is corrected. In particular, fine parts that require high accuracy will be defective even if a slight peeling part occurs, but since the peeling part is corrected by hot isostatic pressing, the defect rate is reduced. is there.

(4) A layer of a powder-mixed photocurable fluid resin obtained by mixing a sinterable inorganic powder material into a photocurable fluid resin that is cured by light is irradiated with an optical image to form a photocurable layer, By sequentially stacking and forming this photo-curable layer, an optical modeling step of modeling a three-dimensional model, a resin removing step of removing a resin component of the powder-mixed resin model to form a powder-mixed model, and A sintering step of heating the powder-mixed shaped body into a sintered body, and a sintered body manufacturing method comprising a hot isostatic pressing step, wherein the powder-mixed shaped body manufactured in the optical shaping step comprises: A molded body comprising a support portion that supports the molded body integrally molded with the powder mixed resin molded body,
The method for producing a sintered body of a powder-mixed stereolithography body, further comprising a step of removing the supporting portion after the isotropic pressure treatment step. (Example) Examples 2-5 correspond. (Operation / effect) In the process of degreasing and sintering a powder-mixed resin molded body having a complicated three-dimensional structure, the powder-mixed resin molded body is placed on a heat-resistant block or heat-resistant powder in a high temperature furnace. At this time, unless placed so that partial stress due to gravity is not applied, deformation due to stress occurs during degreasing and sintering. In particular, it is extremely difficult to place a complicated three-dimensional structure or a fine structure which is a component of a micromachine so that partial stress is not concentrated because the shape is complicated. Furthermore, since shrinkage occurs in the degreasing / sintering process, the shrinkage in the degreasing / sintering process causes stress due to the difference in shrinkage ratio between the heat-resistant block and powder, which causes deformation. is there.

Further, in the case of sintering a powder material such as BaTiO ₃ material, if it is placed directly on the heat resistant block, it reacts with the component of the heat resistant block such as SiO ₂ and melts. Al ₂ O on the block
₃ , the spreading of ZrO ₂ powder must be done. In particular, PZT and PLZT, which have piezoelectric properties, have a problem that the powder properties on the heat-resistant block must be appropriately selected because the piezoelectric properties change even with a slight chemical change.

As in the present embodiment, the supporting portion that supports the powder-mixed resin molded body is integrated with the powder-mixed resin molded body, and the supporting portion that supports the desired molded body itself serves to reduce the contact area. The frictional force is reduced and the deformation is reduced. Furthermore, since the molded body and the support portion are made of the same material, the support portion that supports the shrinkage of degreasing and sintering shrinks at the same ratio as the structure,
Only the support portion is deformed when contracted, and the desired shaped body is less likely to receive the frictional force when contracted, so that the deformation can be minimized. Further, since only the supporting portion is in direct contact with the heat resistant block, there is an effect that the desired shaped body can be obtained without causing dissolution or change in characteristics of the desired shaped body due to a chemical reaction. (5) In the method for producing a sintered body according to (4) above, a powder-mixed stereolithography structure is characterized in that hot isostatic pressing is performed as the sintering step or after the sintering step. Body sintered body manufacturing method. (Example) Example 2 is applicable. (Function / effect) In the process of degreasing and sintering a powder-mixed resin molded body having a complicated three-dimensional structure, the powder-mixed resin molded body is placed on a heat-resistant block or heat-resistant powder in a high-temperature furnace. At this time, unless placed so that partial stress due to gravity is not applied, deformation due to stress occurs during degreasing and sintering. In particular, it is extremely difficult to place a complicated three-dimensional structure or a fine structure which is a component of a micromachine so that partial stress is not concentrated because the shape is complicated. Furthermore, since shrinkage occurs in the degreasing / sintering process, the shrinkage in the degreasing / sintering process causes stress due to the difference in shrinkage ratio between the heat-resistant block or powder and deformation occurs. is there.

Further, in the case of sintering a powder material such as BaTiO ₃ material, if it is placed directly on the heat-resistant block, it reacts with the component of the heat-resistant block such as SiO ₂ and melts. Al ₂ O on the block
₃ , the spreading of ZrO ₂ powder must be done. In particular, PZT and PLZT, which have piezoelectric properties, have a problem that the powder properties on the heat-resistant block must be appropriately selected because the piezoelectric properties change even with a slight chemical change.

As in the present embodiment, the supporting portion that supports the powder-mixed resin molded body is integrated with the powder-mixed resin molded body, and the supporting portion that supports the desired molded body itself serves to reduce the contact area. The frictional force is reduced and the deformation is reduced. Furthermore, since the molded body and the support portion are made of the same material, the support portion that supports the shrinkage of degreasing and sintering shrinks at the same ratio as the structure,
Only the support portion is deformed when contracted, and the desired shaped body is less likely to receive the frictional force when contracted, so that the deformation can be minimized. Further, since only the supporting portion is in direct contact with the heat resistant block, there is an effect that the desired shaped body can be obtained without causing dissolution or change in characteristics of the desired shaped body due to a chemical reaction.

(6) In the method for producing a sintered body according to (4) above, the powder-mixed resin molded body is provided so as to be in contact with a supporting portion for supporting the powder-mixed resin molded body and the supporting portion. A method for producing a sintered body, further comprising a table. (Example) Example 3 is applicable. (Operation / Effect) The powder-mixed resin molded body further includes a support portion and a base, so that the stress exerted on the powder-mixed resin molded body due to gravity is partially supported from the bottom surface portion by the support portion and the base. Even in a molded body in which the stress due to the stress increases, the influence of the stress can be reduced. Further, since the supporting portion can be formed in several places, the powder-mixed resin shaped body can be stably supported. Therefore, the desired deformation of the sintered body is reduced. In addition, the supporting part, the base, and the powder-mixed resin molded body are made of the same material so that degreasing and
Since the supporting part and the powder-mixed resin molded body shrink at the same ratio as the molded body even with respect to shrinkage during sintering and hot isostatic pressing,
There is an effect that deformation of the powder-mixed resin shaped body can be prevented without receiving frictional force when the structure shrinks.

(7) In the method for producing a sintered body according to the above (4), the powder-mixed resin shaped body has a supporting portion and a rod-shaped body, and the powder-mixed resin shaped body is the supporting portion. A method for producing a sintered body, characterized in that the sintered body is attached to a rod-shaped body. (Example) Example 4 is applicable. (Operation / Effect) The powder-mixed resin molded body has a support portion and a rod-shaped body, and the powder-mixed resin molded body is hung in the furnace by the action of being attached to the rod-shaped body via the support portion. You can This is especially effective when the weight of the powder-mixed resin shaped body is small.

Since the shape of the supporting portion may be hook-shaped or key-shaped, the shape of the supporting portion can be changed according to the space inside the furnace even in a small-sized furnace, so that the space can be effectively used. There is an effect. (8) The method for producing a sintered body according to the above (4), wherein the support portion is formed on the same laminated surface of the powder-mixed resin shaped body. (Structure) The fourth embodiment is applicable. (Operation / Effect) The operation time of forming the support portion can be shortened by the operation that the support portion is formed on the same layered surface of the powder-mixed resin shaped body. In order to model an optical molded article, a powder-mixed curable resin is cured in a two-dimensional plane to form a thin film-shaped cured layer, and a plurality of layers are stacked to form a desired three-dimensional molded article. Therefore, in the manufacturing method of the present sintered body, since it is sufficient to perform the molding on the same plane as the two-dimensional plane for forming the stereolithography body so that a part thereof serves as the support portion, the support portion is formed. Therefore, it is not necessary to stack a plurality of cured layers. Therefore, the number of times the elevator of the stereolithography machine is moved is reduced, and the molding time of the powder-mixed resin molding can be shortened.

(9) In the method for producing a sintered body according to (4) above, a cutout having a minimum cross-sectional area is provided in the support portion of the molded body in the vicinity of the powder mixed resin molded body. A method for manufacturing a sintered body, characterized by comprising: (Structure) The fourth embodiment is applicable. (Operation / Effect) For the stereolithography body provided with the supporting portion, the supporting portion must be cut out from the sintered product after the sintering step or the sintering step and the hot isostatic pressing step. Therefore, the shape of the supporting portion has a notch having a minimum cross-sectional area in the vicinity of the powder-mixed resin shaped body, whereby the cutting is facilitated and the cutting can be easily performed by applying stress. Particularly in a complicated three-dimensional fine part, it is considerably difficult to hold the molded body for removing the supporting portion from the powder-mixed resin molded body having the supporting portion, and to position the cutting of the supporting portion. The present mode has an effect that the positioning is performed in advance and the cutting can be easily performed by applying a slight stress.

(10) In the method for producing a sintered body according to the above (9), the periphery of the joint between the supporting portion and the powder-mixed resin shaped body is further relative to the surface of the powder-mixed resin shaped body. A method for manufacturing a sintered body, characterized in that recesses are formed. (Example) Example 4 is applicable. (Operation / Effect) The supporting portion must be cut out after the stereolithography product is made into a sintered product after the sintering process or the sintering process and the hot isostatic pressing process. Therefore, the notch that makes it easier to cut in advance and the recess to prevent the uncut portion of the supporting part from protruding do not stress the notch, and the supporting part can be easily cut off. There is no need to do work. Since it is difficult to maintain the structure of the sintered body particularly in the polishing work of complicated three-dimensional fine parts, the need for the polishing work is a remarkable effect.

(11) The method for producing a sintered body according to the above (4), wherein a plurality of the powder-mixed resin shaped articles are provided. (Example) Examples 4 and 5 correspond. (Operation / Effect) Since a plurality of powder-mixed resin shaped bodies are provided, a plurality of powder-molded resin shaped bodies can be handled at once in the furnace. In particular, it was difficult to handle minute parts and arrange them in a certain direction and put them in a furnace, but it was difficult to handle them because there were multiple desired three-dimensional powder-mixed resin moldings. Easy to handle. In addition, since a plurality of desired three-dimensional powder-mixed resin shaped bodies can be shaped in a certain direction, it is not necessary for the operator to arrange them in a certain direction, and there is an effect that handling becomes easier.

(12) The method for producing a sintered body according to the above (7), characterized in that a plurality of the powder-mixed resin shaped bodies are provided on a rod-shaped body. (Example) Examples 4 and 5 correspond. (Operation / Effect) Since a plurality of powder-mixed resin shaped bodies are provided, a plurality of powder-molded resin shaped bodies can be handled at once in the furnace. In particular, it was difficult to handle minute parts and arrange them in a certain direction and put them in a furnace, but it was difficult to handle them because there were multiple desired three-dimensional powder-mixed resin moldings. Easy to handle. In addition, since a plurality of desired three-dimensional powder-mixed resin shaped bodies can be shaped in a certain direction, it is not necessary for the operator to arrange them in a certain direction, and there is an effect that handling becomes easier.

(13) The method for producing a sintered body according to the above (7) or (12), characterized in that the rod-shaped bodies to which the powder-mixed resin molded body is attached are combined to form a lattice. Sintered body manufacturing method. (Example) Example 5 is applicable. (Operation / Effect) Due to the effect that the shape of the support portion is a lattice, a large number of desired three-dimensional powder-mixed resin molded bodies can be molded, so more structures can be manufactured by one-time optical molding. Can be modeled. Further, since many structures can be formed, a large number of units can be handled at one time when they are put into the furnace. Especially for fine parts, it is difficult to handle parts, and it was a difficult task to arrange them in a certain direction and put them in the furnace, but by providing multiple desired three-dimensional powder-mixed resin moldings, , The structure becomes larger and easier to handle, and moreover, a plurality of desired three-dimensional powder-mixed resin shaped bodies are oriented in a certain direction, so that the operator does not need to arrange them in a certain direction, which is an effect that it is easier to handle. is there.

(14) The method for producing a sintered body according to the above (13), further comprising three-dimensionally combining the powder-mixed resin shaped bodies combined in the lattice pattern. . (Example) Example 5 is applicable. (Action / effect) By combining three-dimensional grids,
Since more structures can be formed, a large number of units can be handled at one time when they are put into the furnace. Especially for fine parts, it is difficult to handle parts, and it was a difficult task to arrange them in a certain direction and put them in the furnace, but by providing multiple desired three-dimensional powder-mixed resin moldings, , The structure becomes larger and easier to handle, and moreover, a plurality of desired three-dimensional powder-mixed resin molded bodies face in a fixed direction, so that the operator does not need to arrange them in a fixed direction,
It has the effect of being easier to handle.

[0118]

EFFECTS OF THE INVENTION In the method for producing a sintered body according to the first aspect of the present invention, by performing hot isotropic pressure treatment, the grain growth of the sintered body is promoted, and at the same time, the state of the minimum surface energy, that is, the grain boundary is obtained. Since a change occurs in the direction of decreasing the surface area of the particles, the particles grow so as to eliminate the minute gaps, and there is no peeling portion that can occur in the regulated liquid surface method.

By the method for producing a sintered body of the first invention, it is possible to provide a homogeneous shaped body having no peeling portion. According to the second aspect of the present invention, since the supporting portion that supports the desired three-dimensional powder-mixed resin molded body is provided integrally with the powder-mixed resin molded body, partial stress due to gravity applied to the powder-mixed resin molded body is reduced. It can be reduced, and the deformation during sintering and hot isostatic pressing is reduced. Further, since the stereolithography body and the support portion can be made of the same material, the proportion of the support portion supporting the shrinkage during degreasing / sintering / hot isostatic pressing is the same as that of the stereolithography body. Therefore, it is possible to prevent the deformation without being affected by the contraction of the stereolithography object.

According to the third aspect of the present invention, a desired three-dimensional powder-mixed resin molded body is provided with a supporting portion for supporting the molded body, and the supporting portion is provided with a notch for easily cutting the supporting portion. Further, a concave portion is provided around the support portion so that the cutout portion of the support portion does not protrude. With this configuration, it is possible to easily cut off the supporting part and the sintered body from the sintered product of the powder-mixed resin molded product simply by applying stress to the supporting part, and further to remove the protruding part after cutting. No need to polish.

[Brief description of drawings]

FIG. 1 is a flowchart of a conventional stereolithography process.

FIG. 2 is a conventional stereolithography process, which is based on a regulated liquid level method.

FIG. 3 is a photolithography process of a conventional example, which is based on a free liquid surface method.

FIG. 4 is a flow chart proposed for forming a metal or ceramic structure to which conventional stereolithography is applied.

FIG. 5 is a diagram showing a sintered body of a powder-mixed photo-curable resin that is sintered without performing hot isostatic pressing.

FIG. 6 is a diagram showing a sintered body subjected to the hot isostatic pressing treatment of the present invention.

FIG. 7 shows a state diagram when a powder-mixed photocurable resin is put into a furnace when degreasing and sintering are performed according to a conventional example.

FIG. 8 shows a state diagram when a powder-mixed photocurable resin is put into a furnace when degreasing and sintering are performed according to a conventional example.

FIG. 9 is a flowchart showing a method for producing a powder-mixed photocurable resin sintered body of the present invention.

FIG. 10 is a schematic view of a pressure vessel of the hot isostatic pressing apparatus.

FIG. 11 is a diagram showing an aspect of a modeled object having a supporting portion of the present invention.

FIG. 12 is a diagram showing an embodiment in which a shaped article having a support portion of the present invention is put into a furnace when being sintered.

FIG. 13 is a process diagram showing post-treatment of a modeled object having a supporting portion of the present invention.

FIG. 14 is a diagram showing one mode of a modeled object having a supporting portion of the present invention.

FIG. 15 is a diagram showing an embodiment in which a shaped article having a supporting portion of the present invention is put into a furnace when being sintered.

FIG. 16 is a process diagram showing post-treatment of a modeled object having a supporting portion of the present invention.

FIG. 17 is a diagram showing one mode of a modeled object having a supporting portion of the present invention.

FIG. 18 is a diagram showing an embodiment in which a shaped article having a supporting portion of the present invention is put into a furnace when being sintered.

FIG. 19 is a process diagram showing post-treatment of a modeled object having a supporting portion of the present invention.

FIG. 20 is a diagram showing one mode of a modeled object having a supporting portion of the present invention and further including a notch.

FIG. 21 is a diagram showing one mode of a modeled object having a supporting portion of the present invention, in which a notch and a recess are further provided.

FIG. 22 is a process drawing showing post-treatment of a shaped article having a supporting portion, a notch and a recess according to the present invention.

FIG. 23 is a diagram showing one mode of a molded article of the present invention in which a plurality of desired three-dimensional powder-mixed resin molded bodies are provided.

FIG. 24 is a diagram showing one mode of a molded article of the present invention in which a plurality of desired three-dimensional powder-mixed resin molded bodies are provided.

FIG. 25 is a diagram showing one mode of a shaped article having a supporting portion of the present invention.

[Explanation of symbols]

1 ... Photocuring layer, 2 ... Tank, 3 ... Glass plate, 4 ... Light, 5
Photocurable fluid resin, 6 Elevator, 21 ... Side surface of powder mixed photocurable resin molded body, 22 ... Void formed between layers of powder mixed photocurable resin molded body, 20, 40, 51, 6
2, 70, 80, 110, 200, 210 ... Powder-mixed photo-curable resin molded body, 24 ... Heat-resistant dish, 25 ... Heat-resistant powder, 26, 43, 53, 72 ... Heat-resistant block, 4
1, 50, 61, 71, 82 ... Supporting portion, 42 ... Stand, 5
2, 60 ... Rod-shaped body, 65, 73 ... Remaining part after notch of support part, 74, 63 ... Notch, 64 ... Recess, 81 ... Lattice support, 300 ... Pressure vessel, 301 ... Valve, 302 ... Insulation Material, 303 ... Heater, 304 ... Powder mixed resin molded body.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B32B 27/16 B32B 27/16 27/20 27/20 Z G02B 1/02 G02B 1/02 // B29K 105: 24

Claims (3)

[Claims] 1. A photocurable layer is formed by irradiating a light image on a layer of a powder-mixed photocurable fluidized resin obtained by mixing a sinterable inorganic powder material into a photocurable fluidized resin that is cured by light. By sequentially stacking and forming a photo-curing layer, a stereolithography process for molding a three-dimensional molded body, a resin removal process for removing a resin component of the powder-mixed resin molded body to form a powder-mixed molded body, and the powder A method for producing a sintered body, comprising the step of heating a mixed shaped body to form a sintered body, wherein the sintering step is performed by hot isostatic pressing, or the sintering step is performed. A method for manufacturing a sintered body of a powder-mixed stereolithography body, which is characterized in that hot isostatic pressing is further carried out after the above process. 2. A layer of a powder-mixed photocurable fluid resin obtained by mixing a sinterable inorganic powder material in a photocurable fluid resin that is cured by light is irradiated with a light image to form a photocurable layer. By sequentially stacking and forming a photo-curing layer, a stereolithography process for molding a three-dimensional molded body, a resin removal process for removing a resin component of the powder-mixed resin molded body to form a powder-mixed molded body, and the powder A sintered body manufacturing method comprising a sintering step of heating a mixed molded body to form a sintered body, and a hot isostatic pressing step, wherein the powder mixed molded body manufactured in the optical molding step comprises: A powder-mixed resin molded body, which is a molded body including a support portion that supports the molded body integrally formed with the powder-mixed resin molded body, further comprising a step of removing the support portion after the isotropic pressure treatment step. For producing a sintered body of the powder-mixed stereolithography body. 3. The method for manufacturing a sintered body according to claim 2, wherein the support portion of the molded body is provided with a notch having a minimum cross-sectional area in the vicinity of the powder mixed resin molded body. And a method for manufacturing a sintered body.