JP3193459B2 - Manufacturing method of sintered body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a sintered body formed by sintering ceramic or metal powder.

[0002]

2. Description of the Related Art In the production of powder metallurgy and ceramics, various methods such as mold molding, hydrostatic molding, hot press molding, tape molding, extrusion molding, and casting are performed. For example, JP-A-59-229403 and JP-A-62-27
No. 0458 discloses a method for producing a molded article having a complicated shape. In this method, after kneading ceramic or metal powder and organic binder, injection molding,
Thereafter, the organic binder is removed by degreasing, and sintering is performed.

FIGS. 53 and 54 show a molded body 201 formed by such a method. That is, in FIG.
A molded body 131 formed by providing holes at both ends in a ring shape by the injection molding, and a molded body 132 provided with holes at both ends in a ring shape having a larger diameter than the molded body are prepared.
After alignment with each other on the mold 143, the mold 143 is separated so as not to contact with each other, and degreased and sintered in the mold 143. Therefore, this compact 20 obtained after sintering
1 is formed in a ring shape, and holes 2 are formed at both ends thereof.
02 is provided. After this molding, the plurality of molded bodies 20 are so formed that the holes 202 communicate with each other.
1 is assembled, and a connecting pin 203 is inserted into a hole 202 and caulked to manufacture an assembly 200 in which a plurality of molded bodies 201 are connected.

FIG. 55 shows a molded body 220 manufactured by the method disclosed in Japanese Patent Application Laid-Open No. 1-133985,
The bottom part 221 made of a ceramic porous sintered body and the side wall part 222 made of a ceramic sintered body form a box shape. The molded body 220 is manufactured by the side wall 22 made of a mixture of ceramics and an organic binder.
2 and a bottom portion 221 made of a composition obtained by adding a thermally decomposable foaming agent to the mixture to form a molded body by insert injection molding or two-color molding, and thereafter, the molded body is degreased and sintered. ing.

[0005]

However, in order to manufacture the assembly 200 shown in FIGS. 53 and 54, after molding the molded bodies 201, the molded bodies 201 are aligned with each other, and the connecting pins 203 are inserted. The number of steps is increasing because of the need to tighten. In addition, since the molded bodies 201 are in contact with each other at the connection portion by the connection pin 203, the slidability is reduced. For this reason, in order to ensure the slidability between the molded bodies, it was necessary to inject a lubricant such as oil into the contact portions of the molded bodies.

On the other hand, in the method of manufacturing the molded body 220 shown in FIG. 55, since the bottom portion 221 and the side wall portion 222 are joined, it is not possible to produce an assembled molded body that is in a mutually movable state.

The present invention has been made in view of the above circumstances, and has as its object to provide a method of manufacturing a sintered body that can be assembled at the same time as injection molding so that assembly after molding is unnecessary.

Another object of the present invention is to provide a method of manufacturing a sintered body that does not require assembling after molding for a plurality of molded bodies having movable parts that can move with each other.

[0009]

According to the production method of the present invention, an injection molding step of injection molding a kneaded body of ceramic or metal powder and an organic binder to obtain a molded body, and degreasing the injection molded molded body. A degreasing step, a sintering step of sintering the degreased molded body, a sliding treatment step of attaching a sliding agent to the surface of the molded body formed in any of the above steps, and Injection-molding a kneaded body of ceramics or metal powder and an organic binder with respect to the molded body to which the sliding treatment agent is attached, followed by degreasing and sintering, and the injection molding step is performed at least twice or more. It is characterized in that the molded body is repeatedly assembled and the sliding treatment step is performed between the injection molding step and the injection molding step.

The production method of the present invention comprises a primary injection molding step of kneading a ceramic or metal powder and an organic binder, and then performing injection molding to form a primary injection molded body. A sliding treatment step of adhering a sliding treatment agent to the surface of the resin, and a secondary injection molding step of injection molding the kneaded body into the primary injection molded body after the sliding treatment step to form a secondary injection molded body And a step of molding the final injection molded body by repeating the sliding treatment step and the sequential injection molding step, a degreasing step of degreasing the final injection molded body, and a sintering step of sintering after degreasing. It is characterized by having.

Further, in the present invention, a primary injection molding step of kneading a ceramic or metal powder and an organic binder and then performing injection molding to form a primary injection molded body;
Next, a degreasing step of degreasing the injection molded body, a sliding treatment step of attaching a sliding agent to the surface of the degreased body, and injection molding the kneaded body to the degreased body to which the sliding agent has been attached. 2
A secondary injection molding step of molding the next injection molded body, a step of sequentially repeating the degreasing step, the sliding treatment step, and the injection molding step as necessary to form a molded body, and sintering the molded body after degreasing A sintering step of sintering the degreased body obtained by degreased the primary injection molded body into a sintered body, and applying a sliding treatment agent to the surface of the sintered body. A sliding treatment step of adhering, and molding a kneaded body into the sintered body to which the sliding treatment agent is adhered to form a secondary injection molded body 2
Next injection molding step, and if necessary, a step of sequentially repeating a degreasing step, a sintering step, a sliding treatment step, and an injection molding step to form a final injection molded body, and after degreasing this final injection molded body, And a step of sintering.

Further, the present invention provides a sliding treatment step of attaching a sliding treatment agent to the surface of a component made of ceramics or metal, and a ceramic or metal powder and an organic binder attached to the component to which the sliding treatment agent is attached. An injection molding step of molding an injection molded article by injection molding a kneaded body of the above, and a step of molding the final injection molded article by repeating the sliding processing step and the injection molding step; And sintering after molding.

[0013]

In any of the above constructions, since the sliding treatment agent adheres to the surface of the injection-molded, degreased or sintered molded body, the injection-molded bodies do not come into contact with each other. As is well known, when sintering is performed after degreasing in the contact state of the injection molded body, the contact surface is welded and integrated, but in the non-contact state as described above, sintering that does not cause integration by welding is performed. be able to. Therefore, each injection molded body is injection-molded so as to be in an assembled state, and each injection molded body is brought into a non-contact state with a sliding agent, so that assembly after sintering becomes unnecessary and sufficient function is achieved. A molded body having a movable portion that can be formed can be formed.

[0014]

Embodiment 1 FIG. 1 shows a state in which a molding die is attached to an injection molding machine, and FIG. 2 shows a state in which a movable platen is rotated by 180 ° with respect to FIG. The injection molding machine has two nozzles and a shut-of nozzle for selectively closing one of the nozzles. In these figures, a fixed-side platen 1 and a movable-side platen 2 are arranged to face each other, and the fixed-side platen 1 is provided with a heating cylinder 3, while the movable-side platen 2 is provided with a rotary shaft 4 connected to a hydraulic cylinder. Have been. A first fixed die 13 and a second fixed die 14 are attached to the fixed platen 1, and the first movable die 11 and the second fixed die 14 are mounted on the movable platen 2 facing these fixed die 13 and 14. Two movable dies 12 are attached. In FIG. 1, the first fixed mold 13 and the first movable mold 11 face each other, and the second fixed mold 14 and the second movable mold 12 face each other.
In FIG. 2 rotated by 0 °, the second movable mold 12 faces the first fixed mold 13, and the first movable mold 11 faces the second fixed mold 14. , 14 and the movable dies 11, 12 are combined.
In this case, the first and second movable molds 11 and 12 have the same configuration and shape, and the first movable mold 11 (or the second movable mold 12) is in close contact with the first fixed mold 13. The first movable mold 11 (or the second movable mold 12) is in close contact with the second fixed mold 14 while the cavity of the primary injection molded body is formed by A cavity having a shape obtained by assembling with the molded body is formed.

FIGS. 3 to 5 show a molded article formed by the present embodiment. FIG. 3 shows the primary injection molded body 21,
A boss 21b stands upright at a predetermined position of the ring portion 21a. FIG. 4 shows a secondary injection molded body 22 that is assembled by injection into the primary injection molded body 21. A boss hole 22b is formed at a predetermined position of a ring portion 22a. The molded body 23 of FIG. 5 shows a state where the boss 21b of the primary injection molded body 21a is inserted into the boss hole 22b and assembled.

FIGS. 6 and 7 show a state in which the first movable mold 11 and the first fixed mold 13 are brought into close contact with each other in order to form the primary injection molded body 21. In these figures, a first fixed die 13 is provided with a fixed plate 32 fixed to a fixed side mounting plate 31.
And a sprue bush 34 having a sprue 33 penetrating the fixed side mounting plate 31 and the fixed plate 32, and attached to the fixed side mounting plate 31 so as to communicate with the sprue bush 34 and fixed to the fixed side platen 1. And a locate ring 35 for fixing the mold. On the other hand, the first movable mold 11 includes a movable plate 42 attached to a movable side attachment plate 41 via a spacer block 43, a protruding plate 44 provided on the movable plate 42 so as to be vertically movable, and a primary injection molding. The protruding rod 4 erected on the protruding plate 44 to protrude the body
5 and the protruding plate 4 so as to correspond to the runner 36.
4 and a protruding rod 46 provided upright.

Further, fitting portions 37 and 47 are formed at positions where the fixed plate 32 and the movable plate 42 face each other, and a fixed insert 38 is mounted on the fitting portion 37 on the fixed plate 32 side. 4
A movable insert 48 is attached to the fitting portion 47 on the second side. The fixed insert 38 is for molding the outer shape of the primary injection molded body 21, and includes a flat portion facing the parting line surface and a convex portion for molding the central portion of the ring portion 21 a of the primary injection molded body 21. And the boss 2 of the primary injection molded body 21
1b is provided. The slide insert 39 indicated by a broken line in FIG. 6 forms the boss 21 b of the ring portion 21 a of the primary injection molded body 21. The base end of the slide insert 39 is retracted from the center hole of the primary injection molded body 21 by the operation of an angular pin (not shown) when the mold is opened, so that the primary injection molded body 21 can be easily taken out. ing. On the other hand, the movable insert 48 is the primary injection molded body 21.
The molding surface 49 is formed at a position facing the fixed insert 38.

FIGS. 8 and 9 show the movable platen 2 (FIG. 1).
And FIG. 2) is rotated by 180 °, and the first movable mold 1 is rotated.
1 shows a state in which it is in close contact with the second fixed mold 14. In these figures, a second fixed die 14 is a sprue bush 5 having a fixed plate 52 fixed to a fixed-side mounting plate 51 and a sprue 53 penetrating the fixed-side mounting plate 51 and the fixed plate 52.
4 and a locate ring 55 attached to the fixed-side attachment plate 51. A fixed insert 58 is attached to a portion of the second fixed die 14 facing the movable insert 48 of the first movable die. The fixed insert 58 forms the secondary injection molded body 22, and has a molding surface 59 corresponding to the outer shape of the molded body 22.

FIG. 10 shows the manufacturing process of this embodiment, which will be specifically described below with reference to FIG. Average particle size 10μ
m of stainless steel (SUS316L) powder, 91 wt%, polystyrene 3 wt%, acrylic 3 wt%, wax 2 wt%, stearic acid 1 w as organic binder
t% is put into a kneading machine, kneaded, and then put into a granulator (not shown), granulated into pellets, and then put into an injection molding machine.

Meanwhile, the movable-side up with respect to the fixed-side platen 1
The Latin 2 is advanced to clamp the first movable mold 11 and the first fixed mold 13, and the second movable mold 12 and the second fixed mold 14, and the pellets are melted to form the first mold. Movable mold 11
In addition, the primary injection molded body 21 is formed by injecting only into the cavity formed by the first fixed mold 13. Thereafter, the movable platen 2 is retracted and separated from the mold at the parting line, and the first movable mold 11 and the first fixed mold 13 and the second movable mold 12 and the second fixed mold 14 are opened. . At this time, cubic boron nitride (c-BN) 8 having an average particle size of 11 μm dispersed in Fluorinert is used as a sliding treatment agent, and the exposed surface from the movable mold surface including the boss 21b of the primary injection molded body 21 is brushed. It may be applied (spray may be applied) and adhered to the surface of the primary injection molded body 21, thereby forming a c-BN film on the surface of the primary injection molded body 21.

Thereafter, the movable platen 2 is rotated by 180 ° and the first movable mold 11 and the second movable mold 12 are exchanged. And the first fixed mold 13 and the first movable mold 11 and the second fixed mold 14 are clamped. Then, the material obtained by melting the pellets is injected into cavities formed by these molds. That is, in the cavity formed by the first movable mold 11 and the second fixed mold 14, the secondary injection molded body 22 is molded so as to be assembled with the primary injection molded body 21 as shown in FIG. I do. During this molding, the primary injection molded body 21 and the secondary injection molded body 22 are kept in a non-contact state due to the c-BN film dispersed in Fluorinert, and are assembled by the boss 21b and the boss hole 22b. Also keep. Further, a new primary injection molded body 21 shown in FIG. 3 is formed in the cavity formed by the second movable mold 12 and the first fixed mold 13.

After this molding, the movable side platen 2 is retracted from the fixed side platen 1, and the first movable mold 11 and the second fixed mold 14, and the second movable mold 12 and the first fixed mold 13
Are opened, respectively, and the assembled molded body 23 of the primary injection molded body 21 and the secondary injection molded body 22 shown in FIG. 5 is taken out, and the newly injection molded primary injection molded body 21 is formed in the same manner as described above. A coating is formed by applying a sliding agent comprising c-BN dispersed in Fluorinert.

Thereafter, the movable platen 2 is rotated by 180 ° to exchange the first movable mold 11 and the second movable mold 12 again, and the movable platen 2 is advanced to move the first movable mold 11 and the first movable mold 11 together. The first fixed mold 13, the second movable mold 12 and the second
And the above-described operations are repeated to form a molded body 23 in an assembled state of the primary injection molded body 21 and the secondary injection molded body 22 in the assembled state.

After the above molding, the primary injection molded bodies 21 and 2
The molded body 23 assembled with the next injection molded body 22 is transferred to a degreasing furnace (not shown) and heated and degreased. In this degreasing, the molded body 23 is subjected to a heat treatment at a high temperature (about 350 ° C.) to evaporate the florinate, leaving a state in which the c-BN film remains at the joint between the two members. Further, the molded body 23 after the degreasing is transferred to a sintering furnace (not shown) and sintered. The c-BN film remains even during this sintering, and the sintering forms a product in which both members of the primary injection molded body 21 and the secondary injection molded body 22 are rotatably connected to each other by the boss 21b. can do.

In this embodiment, the florinate in which c-BN was dispersed was used as the primary injection molded bodies 21 and 2.
It does not attack the polystyrene, acrylic, wax, and stearic acid that retain the shape of the secondary injection molded body 22, and does not adversely affect the primary molded body even if applied to the primary injection molded body. The boss 21b and the boss hole 22b are kept in a state where the primary injection molded body 21 and the secondary injection molded body 22 are kept out of contact with each other by c-BN dispersed in Fluorinert.
Can maintain the assembled state.

Further, the primary injection molded article in the assembled state and 2
Fluorinert, which is kept in non-contact with the next injection molded body, is removed together with polystyrene, acrylic, wax, stearic acid, etc. in the degreasing step, but c-BN remains on the surface of the molded body, so the primary injection molded body 21 and secondary injection molded body 2
2 can be brought into a non-contact assembled state.

Further, in the sintering step, since the primary injection molded body 21 and the secondary injection molded body 22 after degreasing are kept in non-contact by c-BN, welding does not occur and injection is not performed. SUS316L, which is a component of the molded body, and c
Since it does not react with -BN during sintering, it does not hinder sintering, and c-BN maintains a powder state even after sintering.

From the above, after sintering, the primary injection molded body and the secondary injection molded body each become a sintered body,
The molded product 23 assembled by the bosses and the boss holes can be formed without welding each other.

Therefore, in the first embodiment, since the assembled product 23 can be formed without passing through the assembly process after sintering, not only the molding process can be significantly reduced, but also the assembly is difficult. Even a simple product can be easily manufactured.

Although SUS316L powder is sintered in the above embodiment, ceramics can be sintered instead. In this case, ceramics kneaded with the organic binder and ceramics adhered to the surface of the injection molded body are preferably different kinds, for example, alumina (Al ₂ O ₃ ), titanium oxide (TiO ₂ ),
It can be performed using a combination of zirconia oxide (ZrO ₂ ) and carbon (C). In this embodiment, the same organic binder is used for the primary injection molding and the secondary injection molding as the organic binder of the kneaded body.

FIGS. 11 and 12 show a modification of this embodiment. In this modification , as shown in FIG. 52 , three or more injection molded bodies are molded in a connected state. FIG. 11 shows primary injection molding, and FIG. 12 shows secondary injection molding. In the primary injection molding, as shown in FIG.
And a movable insert 48 attached to the movable plate 42 of the first movable mold 11.
A plurality of primary injection molded bodies 24 are formed in the cavity formed by the above. Each primary injection molded body 24 has a shape in which two bosses 24b are integrally erected from both ends of a ring portion 24a. In this case, the primary injection molded article molded at both ends of the cavity has only one boss.

In the secondary injection molding, after applying Fluorinert in which c-BN is dispersed to the primary injection molded body 24,
As shown in FIG. 12, the fixed plate 52 of the second fixed die 14 is in close contact with the movable plate 42 of the first movable die 11. The movable inserts 48 of the movable plate 42 include the primary injection molded body 24.
The molten pellets are injected into a cavity formed by the movable insert 48 and the fixed insert 58 of the fixed plate 52, so that the primary injection molded product 24 and the secondary injection molded product (shown in FIG. it is possible to mold the molded body shown in FIG. 52 shown) and has a plurality of coupling. In the primary injection molded body 24, the boss 24b can be formed in a reverse tapered shape, so that the primary injection molded body 24 and the secondary injection molded body can be prevented from coming off.

[0033]

Example 2 A pellet having the same composition as in Example 1 was melted,
After injection into a cavity formed by the first movable die 11 and the first fixed die 13 to form a primary injection molded body 21, the movable platen 2 is retracted, and the first molding die 11 and the first Fixed mold 13, second movable mold 12 and second fixed mold 1
4 and each are opened. Thereafter, as shown in FIG. 13, the chamber 60 is placed on the movable platen 2 to cover the primary injection molded body 21. An exhaust port 61 is opened on a side surface of the chamber 60, and the exhaust port 61 is connected to a vacuum pump (not shown). An electron gun 62 and a target 63 are provided above the chamber 60. In this embodiment, the material of the target 63 is silicon oxide (SiO ₂ ).

After such a chamber 60 is brought into close contact with the platen 2, the vacuum pump is operated to operate the chamber 6.
The air in the chamber 60 is exhausted from the exhaust port 61, and the degree of vacuum in the chamber 60 is set to 10 ^-5 Torr. At this degree of vacuum, an electron beam is emitted from the electron gun 62 and the target 63
To deposit SiO ₂ as a sliding treatment agent on the surface of the primary injection molded body 21. After the vapor deposition is completed, the atmosphere is introduced into the chamber 60 to be separated from the platen 2.

Thereafter, the first movable mold 11 and the second movable mold 12 are exchanged, and the first movable mold 11 and the second fixed mold 14, and the second movable mold 12 and the first fixed mold 12 are replaced. 13 are clamped respectively to form a molded body 23 (see FIG. 5) composed of the primary injection molded body 21 and the secondary injection molded body 22 in an assembled state and a new primary injection molded body 21.

Thereafter, the molded body 23 in the assembled state of the primary injection molded body 21 and the secondary injection molded body 22 is transferred to a degreasing furnace (not shown), and is heated and degreased. And sintered.

In the second embodiment, the SiO.sub.2 deposited on the primary injection molded body 21 is the primary injection molded body ₂ in the assembled state.
1 are both holding the secondary injection-molded body 22 in a non-contact state, without any reaction also SUS316L which is a component of the molded body during degreasing and during sintering, moreover SiO ₂
Since it itself does not react, a deposited film is formed even after sintering.

Therefore, in the second embodiment as well, the first embodiment
In the same manner as described above, since molding can be performed without going through the assembly process after sintering, the assembly process can be greatly reduced. In particular, in this embodiment, since a vapor-deposited thin film is used as a means for preventing contact between the injection molded bodies, even a fine component can be manufactured without any problem.

In this embodiment, the electron gun and the target are arranged one by one. However, when it is difficult to form a substantially uniform thin film due to the shape of the injection molded body, the shape of the molding die, etc., the electron gun and the target are used. By disposing a plurality of targets, a uniform thin film can be formed.

[0040]

Embodiment 3 First movable mold 11 and first fixed mold 13
After the primary injection molded body 21 is molded, the movable side platen is retracted to open the first movable mold 11, the first fixed mold 13, and the fixed mold 14 of the second movable mold 12, respectively.
As a sliding treatment agent, silicon nitride (Si ₃
N ₄ ) An ultraviolet curable resin in which powder is dispersed is applied to the surface of the primary injection molded body 21. Then, as shown in FIG. 14, the ultraviolet irradiation device 65 is transported above the first movable mold 11, and the primary injection molded body coated with the ultraviolet curable resin is irradiated with ultraviolet light to cure the resin. . Thereafter, the ultraviolet irradiation device 65 is carried out, the first movable mold 11 and the second movable mold 12 are exchanged, and the first movable mold 11 and the second fixed mold 14, and the second movable mold 12 and the second The first fixed mold 13 and the first injection molded body 2 are clamped, respectively.
2 and a new primary injection molded body in an assembled state. Furthermore, after that, the primary injection molded body 2
Molded body 23 assembled with primary and secondary injection molded bodies 22
Is transferred to a degreasing furnace (not shown), heated and degreased at 350 ° C., and further transferred to a sintering furnace (not shown) for sintering.

In Example 3, the UV-curable resin in which Si ₃ N ₄ dispersed in the primary injection molded article was
It does not attack the polystyrene, acrylic, wax, and stearic acid holding the primary injection molded article and the secondary injection molded article, and has no adverse effect on the primary injection molded article and the secondary injection molded article. And at the time of degreasing (350 ° C)
Is removed together with these organic binders by heating. Further, the primary injection molded and the secondary injection molded, together are kept non-contact with Si ₃ N ₄ dispersed in an ultraviolet-curable resin, the structure of the Si ₃ N ₄ is formed article after degreasing Since it does not react at all with SUS316L, which is an element, and does not react with itself, the powder state is maintained even after sintering. Therefore, the primary injection molded body and the secondary injection molded body become sintered bodies by sintering, and a product assembled by the bosses and the boss holes can be formed without welding each other.

In the third embodiment, as in the first and second embodiments, the compact can be formed without passing through the assembling process after sintering, so that the assembling process can be greatly reduced. Further, as means for preventing contact between the injection molded articles, Si ₃
Since the ultraviolet curable resin in which N ₄ powder is dispersed is used, the primary injection molded body immediately after injection molding and the secondary injection molded body can be firmly bonded. Therefore, breakage during transfer from the injection molding process to the degreasing process can be significantly reduced.

In this embodiment, one ultraviolet irradiation device is provided. However, unevenness occurs in the ultraviolet light to be irradiated due to the shape of the injection molded body, the shape of the molding die, etc. In the case where there is no curing, a plurality of ultraviolet irradiation devices may be provided. Further, as a means for dispersing the ceramic powder, an ultraviolet curable resin is used, but any substance may be used as long as it does not corrode the organic binder holding the injection molded body, for example, hexane. , Ethanol, isopropyl alcohol and the like.

Further, ceramics as a sliding treatment agent for preventing welding during sintering may be any substance as long as it does not react with the substance constituting the injection molded body and does not react with itself. It does not matter, alumina (Al ₂ O ₃ )
Sialon, silicon carbide (SiC), TiO ₂ —Al ₂ O
_{3, Al 2 O 3 -ZrO 2} , hexagonal boron nitride (h-B
N) or PBN.

[0045]

Fourth Embodiment FIG. 15 shows a manufacturing process according to a fourth embodiment of the present invention. First, stainless steel having an average particle size of 8 μm (SUS31
6L) 3 wt% of polystyrene, 3 wt% of polyethylene, 2 wt% of wax, and 1 wt% of stearic acid are kneaded with 91 wt% of powder as an organic binder, and the kneaded body is granulated into pellets. The pellet is put into an injection molding machine. In the injection molding machine, as shown in FIG. 16, a first movable mold 71 and a first fixed mold 72 are respectively attached to a platen, and form a cavity for molding a primary injection molded body by being brought into close contact with each other. These molds 71, 72
And a molten pellet is injected into the cavity to form a primary injection molded body 73.

Thereafter, the primary injection molded body 73 is put into a mixed solution of acetone 90 vol% and ethyl alcohol 10 vol% and degreased to form a primary degreased body 74 shown in FIG. The surface of the degreased body 74 has an average particle size of 12
Fluorinert solution in which μm zirconia oxide (ZrO ₂ ) is dispersed is applied as a sliding agent. The primary degreased body 74 to which the florinate solution has been applied is placed at a predetermined position of the second movable mold 75 as shown in FIG. The second movable mold 75 is in close contact with the second fixed mold 76 to form a cavity having a shape obtained by assembling a primary degreased body and a secondary injection molded body. In this case, both the primary degreased body 74 and the secondary injection molded body 77 have a ring shape,
While the boss stands on the primary degreased body, the secondary injection molded body 7
In FIG. 7, a boss hole is formed at a position where the boss is inserted.

The second movable mold 75 and the second fixed mold 76 are clamped, the pellets are injected into the cavity, and the secondary injection molded body 77 is molded so as to be assembled with the primary degreased body 74. I do.

Thereafter, the assembled primary degreased body 74 and the secondary injection molded body 77 are put into the above-mentioned acetone-ethyl alcohol mixed solution, and then transferred to a degreasing furnace (not shown) to be heated and degreased. Then, it is transferred to a sintering furnace (not shown) and sintered.

In Example 4, the primary injection molded body 7
The mixed solution of acetone and ethyl alcohol to which No. 3 is added selectively dissolves only polystyrene and stearic acid among the polystyrene, polyethylene, wax and stearic acid that hold the primary injection molded article. Therefore, the shape of the primary degreased body 74 is maintained by the polyethylene and wax remaining without being dissolved.

Further, ZrO ₂ applied to the primary degreased body 74
Does not attack the polystyrene, polyethylene, wax, and stearic acid that retain the primary degreased body and the secondary injection molded body, and do not adversely affect these. Further, as described above, the acetone-ethyl alcohol mixture into which the assembly of the primary degreased body and the secondary injection molded body is put is selectively made of only polystyrene and stearic acid among polystyrene, polyethylene, wax and stearic acid. Therefore, the primary degreased body 74 is not further degreased, the shape retention state is not deteriorated, and only polystyrene and stearic acid are selectively dissolved from the secondary injection molded body. .

Then, in the heating degreasing performed in the subsequent step,
Since the remaining polystyrene and wax are removed, there is no adverse effect on sintering. ZrO ₂ is a SUS component that is a component of the primary degreased body and the secondary injection molded body after thermal degreasing.
Since it does not react with 316L at all and does not react with itself, the powder state is maintained even after sintering. From the above, after sintering, the primary degreased body and the secondary injection molded body each become a sintered body, and can be a product assembled by the boss and the boss hole without welding each other.

In the fourth embodiment, an assembled product can be formed without going through the assembly process after sintering.
In addition, since the primary injection molded body is preliminarily degreased, the residue of the organic binder after degreasing, that is, the residue is reduced, so that the sinterability is also improved.

In this embodiment, only the primary degreased body and the secondary injection molded body are combined.
Next injection → Primary degreasing → Secondary injection → Secondary degreasing → Tertiary injection
It may be repeated sequentially, and furthermore, primary injection → primary degreasing →
The injection process of secondary injection → tertiary injection → secondary degreasing may be repeated. That is, any combination of steps may be used as long as a sliding treatment agent made of ceramic is attached to the degreased body and an injection molded body is formed so as to be assembled with the degreased body.

[0054]

Fifth Embodiment FIG. 19 shows a manufacturing process of a fifth embodiment of the present invention. First, stainless steel having an average particle size of 8 μm (SUS31
6L) 91% by weight of powder, 3% by weight of polypropylene as an organic binder, 3 parts of polyphenylene sulfide
wt%, wax 2wt%, stearyl alcohol 1w
Then, the mixture is granulated into pellets. The pellet is put into an injection molding machine. In the injection molding machine, as shown in FIG. 20, a first movable die 81 and a first fixed die 82 are respectively mounted on predetermined platens, and are brought into close contact with each other to form a cavity for molding a primary injection molded body. To form The first movable mold 81 and the first fixed mold 82 are clamped, and the molten pellet is injected into the cavity to form the primary injection molded body 83. Then, the primary injection molded body 83 is transferred to a degreasing furnace to be degreased, and the degreased primary injection molded body is transferred to a sintering furnace for sintering.
The primary sintered body 84 shown in FIG.

The primary sintered body 84 has an average grain size of 15
Fluorine-based grease in which ₃ μm of 3Al ₂ O ₃ -2SiO ₂ is dispersed is applied as a sliding agent, and then placed at a predetermined position on a second movable mold (not shown). The second movable mold is in close contact with a second fixed mold (not shown),
A cavity having a shape obtained by assembling the primary sintered body and the secondary injection molded body is formed. Then, these molds are clamped, and the molten pellet is injected into the cavity to form a secondary injection molded body 85 assembled with the primary sintered body 84. FIG. 22 shows such a molded body, and a primary sintered body 84 and a secondary injection molded body 85
Are formed in a ring shape, a boss is erected on the primary sintered body 84, and a boss hole for inserting the boss is formed on the secondary injection molded body 85.

Thereafter, the assembled primary sintered body 84 and secondary injection molded body 85 are transferred to a degreasing furnace (not shown) to be degreased. Further, the primary sintered body 8 in the assembled state after the degreasing is performed.
The fourth and second injection molded bodies 85 are transferred to a sintering furnace (not shown) and sintered.

In Example 5, the fluorine-based grease dispersed in 3Al ₂ O ₃ -2SiO ₂ applied to the primary sintered body does not affect SUS316L constituting the primary sintered body at all, and Also, since the polypropylene, polyphenylene sulfide, wax, and stearyl alcohol which hold the secondary injection molded body are not affected at all, the primary sintered body 84 and the secondary injection molded body 85 are not affected at all. The primary sintered body and the secondary injection molded body are made of 3Al ₂ O ₃ -2Sl dispersed in fluorine-based grease.
It is kept in a non-contact state by O ₂ and the 3Al
₂ O ₃ -2SiO ₂ itself does not react and maintains a powder state even after sintering. For this reason, after sintering,
The secondary injection molded body becomes a sintered body, and can be a product assembled by bosses and boss holes without welding to the primary sintered body.

In the fifth embodiment, a product in an assembled state can be formed without going through an assembly process after sintering. In addition, since the primary injection molded body is degreased and sintered, it can sufficiently withstand the injection pressure during the secondary injection molding, thereby improving the yield during the secondary injection molding.

In this embodiment, only the primary sintered body and the secondary injection molded body are combined. However, depending on the product shape, etc., primary injection → primary degreasing → primary sintering → secondary injection → Secondary degreasing → tertiary injection may be sequentially repeated, and primary injection → 1
The injection process of secondary degreasing → primary sintering → secondary injection → tertiary injection may be repeated. That is, any combination of steps may be used as long as a slide treatment agent made of ceramics is attached to the sintered body and an injection molded body is formed so as to be assembled with the sintered body. . In addition, the member to which the sliding treatment agent such as ceramics is attached in advance is not limited to a sintered body, and is a member manufactured by other processing methods such as forging and cutting because it is installed at the time of injection molding after the secondary injection. Is also good.

[0060]

Embodiment 6 FIGS. 23 and 24 show a molded body 90 formed according to Embodiment 6 of the present invention. The molded body 90 is formed by connecting a plurality of ring-shaped short tubes 91 in the axial direction, and the short tube 91 has a pair of ears 9 at one end.
2 and a boss that engages with the ear 92 at the other end.
93 are formed. As a material for forming such a molded body 90, stainless steel (SU) having an average particle size of 8 μm is used.
S316L) 91% by weight of powder, 3% by weight of ethylene vinyl acetate copolymer, 3% by weight of polybutyl methacrylate,
A pellet obtained by kneading an organic binder consisting of 2 wt% of wax and 1 wt% of stearamide and granulating is used.

In this embodiment, as shown in FIGS. 25 and 26, the slides 101,
102 and a slide 103 constituting a set of molds,
Between 104, a solid slide core 105 having a circular cross section and an annular slide core 106 are arranged. The slide core 106 is slidably fitted to the slide core 105, and the slide core 106 is
05 can be moved and fixed to an appropriate position.

As shown in FIG. 27, the molding surfaces of the slides 101 and 102 are each formed in an arc shape for molding the outer surface of the short tube 91, and a part of the boss 9 of the short tube 91 is formed.
3 and a pin hole 107 for forming
An ear-shaped recess 108 for forming the ear 92 is drilled,
A second pin 109 is provided upright in the ear-shaped recess 108. On the other hand, the molding surfaces of the slides 103 and 104 are shown in FIG.
As shown in FIG. 8, the molding surfaces are the same as the molding surfaces of the slides 101 and 102, except that the second pin is not formed in the ear-shaped recess 108.

As shown in FIG. 26, the slide core 105 includes a large-diameter portion having a step and a small-diameter portion, and an annular slide core 106 is slidably fitted to the small-diameter portion.
After the slide cores 105 and 106 are arranged at predetermined intervals between the slides 101 and 102, the slides 101 and 102 are clamped to form a cavity for forming a primary injection molded body. .

FIG. 29 shows a state in which the slide core 105, the slide core 106, the slide 101 and the slide 102 are clamped, and a material in which pellets are melted is injected from the sprue 110 into a cavity formed by the mold, thereby performing a primary injection. The molded body 121 is molded. This molded body 12
1 has a shape similar to the perspective view of the short pipe 91,
The bosses are respectively formed at the same time. Next, as shown in FIG. 30, after the slides 101 and 102 are opened, the slide core 106 is retracted by about 1 mm in a direction opposite to the primary injection molded body. Then, a mixed liquid of 60 vol% of silicon oil and 40 vol% of chromina Cr ₂ O _{3 is} applied as a sliding treatment agent so as to fill a gap between the primary injection molded body 121 and the slide core 106, and the primary injection molded body is also coated. 0.1mm on and around the boss
Apply with a thickness of about. Then, as shown in FIG.
The slide core 105, the primary injection molded body 121 and the slide core 106 are moved to the slide 103 and the slide 104.
And move them together. Here the slide core 10
5, slide core 106, slide 103, slide 1
04, a cavity formed by the primary injection molded body 121 is a position where a secondary injection molded body to be assembled by the boss of the primary injection molded body 121 is formed. The material obtained by melting the pellets is injected from the sprue 111, and the secondary injection molded body 122 assembled by the boss of the primary injection molded body 121 and the boss hole of the ear is molded.

Thereafter, as shown in FIG.
3, 104, and slide core 10
33, the slides 103 and 104 are clamped again, and as shown in FIG.
23 is molded. The above mold opening → application of the mixed solution → movement of the slide cores 105 and 106 → slide cores 103 and 1
04 mold clamping → injection molding → slide cores 103 and 104
Is repeated to form the connected molded body 90 shown in FIG.

Thereafter, the slide cores 105 and 106 are pulled out to take out only the connected injection molded body. The connected injection molded body is transferred to a degreasing furnace (not shown),
Degreasing is performed by heating to about 350 ° C. in a normal pressure atmosphere, and the molded body after the degreasing is transferred to a sintering furnace, and is subjected to a vacuum of about 13 ° C.
Heat to 00 ° C and sinter. Thereby, the molded body 90 of FIG. 24 can be manufactured.

In the sixth embodiment, the silicon oil in which Cr ₂ O ₃ is dispersed is applied to the injection-molded article to form the ethylene-vinyl acetate copolymer, polybutyl methacrylate, wax, It does not attack stearamide and has no adverse effect on all injection molded articles. Also, all injection molded products
They are interconnected with a clearance by the silicon oil impregnated with Cr ₂ O ₃ , and at the time of degreasing, the silicon oil decomposes and evaporates, leaving only Cr ₂ O _3, so that there is no Clearance occurs. Furthermore, SUS which is a component of all the injection molded articles after degreasing
Without any reaction and 316L and the Cr ₂ O _3, since the Cr ₂ O ₃ itself does not react, Cr ₂ O ₃ even after sintering are kept powder state.

Therefore, after sintering, a series of injection-molded articles each become a sintered article, and are not welded to each other.
The molded article 90 assembled by the boss hole can be manufactured, and each short pipe 91 can be freely moved by the clearance made of silicone oil.

[0069]

[Embodiment 7] FIG. 34 shows the manufacturing process of Embodiment 7 of the present invention. In this embodiment, as shown in FIGS. 35 and 36, an assembly 130 in which a plurality of ring-shaped short tubes are connected is formed. In these figures, 131 is a short tubular primary molded body formed at the time of primary injection molding, and 132 is a short tubular secondary molded body molded in a connected state with the primary molded body by secondary injection molding. is there. Pin projections 131 a are formed on the outer surfaces of both ends of the primary molded body 131, while small piece-shaped ears 133 are formed on both ends of the secondary molded body 132,
A pin hole 132a into which the pin protrusion 131a is inserted is formed in the ear 133. In FIG. 36, reference numeral 134 denotes a sliding treatment agent provided in a gap between the end faces of the primary molded body 131 and the secondary molded body 132 and in a gap between the pin projection 131a and the pin hole 132a. Agent 13
4, the primary molded bodies 131 and 2 in a connected state are interposed.
The next molded body 132 has a structure that can move mutually.

FIG. 37 shows an injection molding machine applied to this embodiment. The core 143 is attached to the upper platen 141 via the attachment plate 142, and the core 153 is attached to the lower platen 151 via the base 152, so that the upper core 143 and the lower core 153 are attached.
Are opposed to each other. These cores 143 and 153 are relatively positioned by a guide pin 149 and a guide hole into which the guide pin 149 enters. Also, core 1
A pair of cores 155 having a circular outer shape are inserted between 43 and 153 in a state where they are butted on a coaxial line. These cores 155 are cylinders 157 and 158, respectively.
Moves forward and backward on the same axis. Further, a sprue 145 inserted into the nozzle hole 144 and a runner 146 communicating with the sprue 145 are formed in the upper core 143 so that the molten material is injected into a cavity formed by the cores 143, 153 and the core 155. Has become. In this case, the upper core 143 and the lower core 153 are slidable left and right, and primary injection molding and secondary injection molding are performed according to the slide. Reference numeral 59 denotes a motor for sliding the lower core 153, and its screw rod 159a is screwed to the lower core 153. In the figure, reference numeral 147 denotes a cavity for molding a primary molded body, and 148 denotes a cavity for molding a secondary molded body.

Next, the manufacturing method according to the present embodiment will be described.
In the primary injection molding shown in FIG. 34, as shown in FIG. 37, a cavity 147 for the primary molding is connected to the nozzle hole 144 via the runner 146 and the sprue 145, and the mold is closed in this state. FIG. 39 is a view showing the cavity 147 from the parting surface when the core 155 is removed in this mold closed state. Next, 91 wt% of stainless steel (SUS316L) powder having an average particle size of 10 μm, 3 wt% of polystyrene as an organic binder, and 3 wt% of acrylic
%, 2% by weight of wax and 1% by weight of stearic acid are kneaded, pelletized and then melted.
Is injected into a cavity 147 formed in a mold closed state. FIG. 38 is a diagram showing this primary injection molding from the parting surface, and a plurality of primary molded bodies 131 having pin projections 131a (corresponding to the bosses described above) are molded.

After the primary injection molding, the mold is opened. FIG.
0 and FIG. 41 show such a mold opening state, in which the lower core 153 and the core 155 are assembled, and the primary molded body 131 is held by the lower core 153 and the core 155. Then, in this state, siloxane as a sliding treatment agent is sprayed on the primary molded body. FIG. 42 and FIG.
Reference numeral 3 denotes such a sliding treatment step, in which the injection nozzle 161 is caused to enter between the cores to spray siloxane, and the discharge poles 162 are caused to approach the primary molded body 131 to discharge. Chemical formula 1 shows a decomposition reaction of siloxane due to such discharge, whereby Si generated by decomposition of siloxane is produced.
O ₂ and the SiC is deposited on the surface of the primary molded body.

[0073]

Embedded image

Next, as shown in FIG. 44, the cores 143 and 153 are integrally moved in the lateral direction, and the cavity 148 for secondary molding is communicated with the runner 146. Then, as shown in FIG. 45, the mold is closed so that the cores 143 and 153 are in close contact with each other. FIG. 46 shows the cavity 148 from the parting surface when the core 155 is removed in this mold closed state, and FIG. 47 shows the state where the primary molded body 131 is set from the parting surface. After closing the mold, the pellets are melted and injected into the cavity 148 to form a secondary molded body 132 to be assembled with the primary molded body 131. In such injection molding, since SiO ₂ and SiC are adhered to the surface of the primary molded body 131, the secondary molded body 132 passes through the primary molded body 1 via these.
31. After the formation of the secondary formed body 132, the cylinder 158 is driven, as shown in FIG.
The core 155 is slid and pulled out of the molded body 130, and then the mold is opened to hold the assembled molded body 130 on the upper core 143 (FIG. 49). Then, the cores 143 and 153 are slid laterally as shown in FIG.
To unlock. Thereafter, as shown in FIG. 51, the upper core 143 is lowered and separated from the sprue 146, and the molded body 130 is taken out. In addition, the molded body 13
0, the molded body 130 is attached to the lower core 1
The mold may be opened while being held at 53, and then removed. The compact 130 thus taken out is then heated and degreased, and then sintered.

[0075] molding of structures in such embodiment, since the SiO ₂ and SiC as sliding treating agent is interposed in the opening of the primary molded body 131 and the secondary molded body 132, which movable mutually The body 130 can be manufactured without going through an assembly process.

In each of the above embodiments, the step of adhering the sliding agent is inserted between the injection molding and the injection molding. Can be used. Such alcoholates include Si (OC ₂ H ₅ ) ₄ , Al (OC
₃ H ₇ ) ₃ , Ti (OC ₃ H ₇ ) ₄ , Ta (OC
_{2 H 5) 5, Nb (} OC 2 H 5) 5, Zr (OC
_{3 H 7) 4, VO (} OC 3 H 5) 3, Sb (OC
_{2 H 5) 3, Ba (} OCH 3) 2, Sr (OC
H ₃ ) ₂ , LiOC ₃ H ₇ , Hf (OC ₃ H ₇ ) ₄ , L
one of a (OC ₃ H ₇ ) ₃ and Ge (OC ₂ H ₅ ) ₄
Species or a mixture of two or more can be used. By applying these alcoholates to the surface of the molded body, a sintered body having a mutually movable structure in an assembled state can be manufactured.

[0077]

As described above, according to the present invention, a molded article having a complicated shape using ceramics or metal powder can be easily manufactured without going through an assembling step, so that the number of steps can be reduced and the product cost can be reduced. In addition, it is possible to easily manufacture a complicated and fine product which has been extremely difficult to assemble in the past.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an injection molding machine.

FIG. 2 is a cross-sectional view of a main part of an injection molding machine in which a movable platen is rotated by 180 °.

FIG. 3 is a perspective view of a primary injection molded body according to the first embodiment.

FIG. 4 is a perspective view of a secondary injection molded body according to the first embodiment.

FIG. 5 is a perspective view of a molded body of Example 1.

FIG. 6 is a sectional view at the time of primary injection molding of the first embodiment.

FIG. 7 is a sectional view from the side of FIG. 6;

FIG. 8 is a sectional view at the time of secondary injection molding of the first embodiment.

FIG. 9 is a sectional view from the side of FIG. 8;

FIG. 10 is a block diagram of a manufacturing process according to the first embodiment.

FIG. 11 is a sectional view at the time of primary injection molding in a modification of the first embodiment.

FIG. 12 is a sectional view at the time of secondary injection molding in a modification of the first embodiment.

FIG. 13 is a perspective view of the second embodiment.

FIG. 14 is a perspective view of a third embodiment.

FIG. 15 is a block diagram of a manufacturing process according to a fourth embodiment.

FIG. 16 is a perspective view at the time of primary injection molding of Embodiment 4.

FIG. 17 is a perspective view of a primary degreased body according to a fourth embodiment.

FIG. 18 is a perspective view of Example 4 at the time of secondary injection molding.

FIG. 19 is a block diagram of a manufacturing process according to a fifth embodiment.

FIG. 20 is a perspective view of Example 5 at the time of primary injection molding.

FIG. 21 is a perspective view of a primary sintered body according to a fifth embodiment.

FIG. 22 is a perspective view of Example 5 at the time of secondary injection molding.

FIG. 23 is a perspective view of a short tube formed in Example 6.

FIG. 24 is a perspective view of a molded article formed in Example 6.

FIG. 25 is a perspective view of an apparatus used in the sixth embodiment.

FIG. 26 is a sectional view of an apparatus used in the sixth embodiment.

FIG. 27 is a perspective view of a slider of the device used in the sixth embodiment.

FIG. 28 is a perspective view of another slider of the device used in the sixth embodiment.

FIG. 29 is a cross-sectional view of Example 6 at the time of primary injection molding.

FIG. 30 is a sectional view after primary injection molding in Example 6.

FIG. 31 is a cross-sectional view of Example 6 at the time of secondary injection molding.

FIG. 32 is a cross-sectional view after the secondary injection molding in Example 6.

FIG. 33 is a cross-sectional view during the subsequent injection molding.

FIG. 34 is a block diagram of a manufacturing process according to the seventh embodiment.

FIG. 35 is a perspective view of a molded article manufactured according to Example 7.

FIG. 36 is a perspective view of a main part of a molded body manufactured according to the seventh embodiment.

FIG. 37 is a sectional view of an apparatus used in the seventh embodiment.

FIG. 38 is a plan view of the primary injection molding of Example 7.

FIG. 39 is a plan view of a primary injection molding cavity according to a seventh embodiment.

FIG. 40 is a cross-sectional view after the primary injection molding of Example 7.

FIG. 41 is a perspective view of the seventh embodiment after primary injection molding.

FIG. 42 is a cross-sectional view of a state where a sliding treatment agent is applied.

FIG. 43 is a perspective view of a state where a sliding treatment agent is applied.

FIG. 44 is a sectional view showing movement of a core according to the seventh embodiment.

FIG. 45 is a sectional view of Example 7 at the time of secondary injection molding.

FIG. 46 is a plan view of a secondary injection molding cavity of Example 7.

FIG. 47 is a plan view of the secondary injection molding of the seventh embodiment.

FIG. 48 is a sectional view showing a core slide according to the seventh embodiment;

FIG. 49 is a cross-sectional view after the secondary injection molding in Example 7.

FIG. 50 is a sectional view showing removal of a molded product according to the seventh embodiment.

FIG. 51 is a cross-sectional view showing removal of a molded product of Example 7.

FIG. 52 is a perspective view showing another removal of a molded product.

FIG. 53 is a perspective view of an example of a molded body.

FIG. 54 is a sectional view of FIG. 53;

FIG. 55 is a perspective view of a sintered body manufactured by a conventional method.

[Explanation of symbols]

 11 first movable mold 12 second movable mold 13 first fixed mold 14 second fixed mold

──────────────────────────────────────────────────続 き Continuing from the front page (72) Katsumi Sekine 2-43-2 Hatagaya, Shibuya-ku, Tokyo O-limpus Optical Industry Co., Ltd. (72) Naoto Shiga 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Co., Ltd. (72) Michio Shirai, Inventor 2-43-2, Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Co., Ltd. Kenji Haga 2-43-2, Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (72) Inventor Jun Inahashi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (56) References JP-A-61-290007 (JP, A) 61-232277 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C04B 35/00, 35/64 B22F 3/02 B28B 1/24

Claims (10)

(57) [Claims] 1. An injection molding step of injection-molding a kneaded body of ceramic or metal powder and an organic binder to obtain a molded body, a degreasing step of degreasing the injection-molded molded body, and firing the degreased molded body. A sintering step of bonding, a sliding treatment step of attaching a sliding treatment agent to the surface of the molded body formed in any of the above steps, and a molding treatment having the sliding treatment agent adhered in the sliding treatment step. Injection molding a kneaded body of a ceramic or metal powder and an organic binder, followed by degreasing and sintering. The injection molding step is repeated at least twice or more to sequentially assemble the molded bodies, and A method for producing a sintered body, wherein the dynamic treatment step is performed between the injection molding step and the injection molding step. 2. A primary injection molding step of kneading a ceramic or metal powder and an organic binder and then performing injection molding to form a primary injection molded body, and a sliding treatment agent on the surface of the primary injection molded body. , A secondary injection molding step of injection molding the kneaded body into the primary injection molded body after the sliding processing step to form a secondary injection molded body, and the sliding processing step. And a step of forming a final injection molded body by sequentially repeating the injection molding step, a degreasing step of degreasing the final injection molded body, and a sintering step of sintering after degreasing. Method for producing a sintered body. 3. A primary injection molding step in which a ceramic or metal powder and an organic binder are kneaded and then injection molded to form a primary injection molded body, and a degreasing step in which the primary injection molded body is degreased. A sliding treatment step of attaching a sliding treatment agent to the surface of the degreased body; and a secondary injection molding of the kneaded body to the degreased body to which the sliding treatment agent is attached to form a secondary injection molded body. A molding step, a step of forming a molded body by sequentially repeating the degreasing step, the sliding treatment step, and the injection molding step as necessary, and a step of degreased and then sintering the molded body. A method for producing a sintered body, characterized in that: 4. A primary injection molding step of kneading ceramic or metal powder and an organic binder and then injection molding to form a primary injection molded body, and a degreasing step of degreasing the primary injection molded body. A sintering step of sintering the degreased body into a sintered body, a sliding treatment step of attaching a sliding agent to the surface of the sintered body, and a sintered body having the sliding agent attached A secondary injection molding step of injection molding the kneaded body to form a secondary injection molded body, and optionally repeating the degreasing step, the sintering step, the sliding treatment step and the injection molding step, to obtain the final A method for producing a sintered body, comprising: a step of molding an injection molded body; and a step of sintering the final injection molded body after degreasing. 5. A sliding treatment step of attaching a sliding agent to the surface of a ceramic or metal component, and a kneaded body of ceramic or metal powder and an organic binder is applied to the component to which the sliding agent is attached. An injection molding step of injection molding to form an injection molded article, a step of molding the final injection molded article by repeating the sliding processing step and the injection molding step, and degreased after molding of the final injection molded article. And a sintering step. 6. The method for producing a sintered body according to claim 1, wherein the sliding agent is a ceramic. 7. The method according to claim 6, wherein the ceramic is a c-BN coating dispersed in florinate. 8. The method according to claim 6, wherein the ceramic is at least one of a nitride, an oxide, and a carbide. 9. The method according to claim 6, wherein the ceramic is obtained by thermally hydrolyzing an alcoholate. 10. The method for producing a sintered body according to claim 8, wherein said nitride, oxide or carbide is dispersed and attached to an ultraviolet curable resin or fluorine-based grease.