JP6988768B2 - Metal complex manufacturing method and metal complex - Google Patents

Description

The present invention relates to a modeled body manufactured by a immersion treatment using a metal.

A new modeling technique for forming a three-dimensional model (hereinafter referred to as a model) from material particles based on three-dimensional drawing data is attracting attention. One of them, the binder injection method (hereinafter referred to as the binder injection method), is a method in which metal particles, which are material particles, are spread thinly, and an organic binder is injected onto the metal particles to obtain a binder. Metal particles in the injected portion are solidified, and the solidified layers are sequentially laminated to produce a binder having a complicated shape. The produced binder is heated to bond the metal particles to each other, resulting in a porous model having pores.
With this method, various shapes based on 3D drawing data can be flexibly produced, but the strength is inferior to that of a cast body using a mold because the pore ratio of the modeled body is high, and there is a risk of deformation due to its own weight, especially during heating. was there.
Therefore, a treatment for improving the strength by infiltration of a metal, for example, a treatment for melting a metal or alloy having a melting point lower than that of the modeled body, filling the pores of the modeled body, and resolidifying it (for example, a patent) is performed. See Document 1).

Japanese Patent Publication No. 2018-510267

However, it is necessary to remove the binder at the time of forming the binder before the metal is infiltrated, and if this remains, there is a problem that sufficient strength cannot be secured.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a method for producing a metal complex that improves the strength of a modeled body produced by a binder injection method.

In the method for producing a metal composite according to the present invention, a layer of metal particles is formed, and an organic binder is supplied to the layer of the metal particles to bind the metal particles to each other, and the metal particles are bound to each other. A binder forming step of sequentially laminating layers of metal particles to form a binder, a porous body manufacturing step of drying the binder to produce a porous body having pores, and the porous body. The body is infiltrated by heating a copper or copper alloy containing Ti in a reducing atmosphere, and the carbon of the binder reacts with the copper or Ti in the copper alloy, and the metal particles and the copper or the copper are described. It is provided with a step of forming a TiC phase at an interface with a copper alloy.

Further, the metal composite according to the present invention covers a core portion formed by contacting a plurality of metal particles with each other and copper or copper containing Ti that covers the outer periphery of the core portion and is filled between the plurality of metal particles. It is provided with a base portion made of an alloy and an interface portion in which a TiC phase is formed at least a part of the interface between the core portion and the base portion.

According to the present invention, by infiltrating a copper or copper alloy containing Ti into a porous body, carbon remaining on the surface of the metal particles constituting the porous body reacts with Ti, and the metal particles and copper or By forming the TiC phase at the interface with the copper alloy, the residual carbon can be suppressed and the strength of the produced metal composite can be significantly improved.

It is a schematic block diagram of the 3D modeling apparatus which concerns on Embodiment 1 of this invention. It is a schematic block diagram of the porous body which concerns on Embodiment 1 of this invention. It is a schematic block diagram which shows the state of the infiltration treatment of the porous body which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the modeling method of the metal complex piece which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the metal complex which concerns on Embodiment 1 of this invention. It is a relational figure which shows the tensile strength ratio of the metal complex which concerns on Embodiment 2 of this invention.

Embodiment 1.
The inventors focused on the fact that one of the causes of the lack of strength of the model produced by the conventional infiltration treatment was the residual organic component of the binder, and wondered if the organic component could be altered. As a result of diligent studies, it was found that it is possible to react carbon in an organic component with a metal and leave it as a metal compound in the modeling body.
Then, in particular, the strength is increased by reacting titanium and carbon to form TiC, and forming a metal composite that remains as a TiC phase between the metal particles forming the shaped body or at the interface between the metal particles and the infiltrating material. It was confirmed that it could be secured. Hereinafter, the method for producing the metal complex according to the invention and the metal complex will be described.

FIG. 1 is a schematic configuration diagram of a three-dimensional modeling apparatus according to the first embodiment of the present invention. The three-dimensional modeling apparatus 4 has a modeling chamber 7 surrounded by a modeling chamber wall 5 and provided with a table 6 that moves up and down. Metal particles 10 (for example, stainless steel particles) are supplied from the metal particle supply unit 9 provided in the tank 8 to the table 6 in the modeling chamber 7. The supplied metal particles 10 are spread on the table 6 by the squeegee 11 and compacted to form a metal particle layer 12 _{having a thickness t D.}
An organic binder 14 dissolved or mixed in a solvent is ejected from the nozzle 13 onto the formed metal particle layer 12, and the nozzle 13 moves to move the binder 14 to an arbitrary position on the metal particle layer 12. Is supplied. As a result, the plurality of metal particles 10 are bound by the binder 14, and the bound metal particle layers 12 are sequentially laminated to form a three-dimensionally shaped binder 1. FIG. 1 shows the shape of a fan of a ventilation fan as an example of the binder 1.

Next, the obtained binder 1 is taken out from the modeling chamber 7 and dried. Since the solvent component of the binder 14 remains in the binder 1, the solvent component is removed by drying to promote the binding and prevent the binder 1 from being deformed. The drying temperature and drying time for removing the remaining solvent component are, for example, about 200 ° C. and 8 hours.

Next, the dried binder 1 is cooled at room temperature. As shown in FIG. 2, the binder 1 is composed of a plurality of metal particles 10 and a binder 14 that binds them to each other, and becomes a porous body 2 having pores. Since metal particles that are not bound by the binder 14 are present around the porous body 2, they are removed.

Next, as shown in FIG. 3, the dried and cooled porous body 2 is brought into contact with, for example, Ti-containing copper or a Ti-containing copper alloy as the infiltrating material 15 under a hydrogen atmosphere, and heated by the heater 16. Here, the infiltrating material 15 is made into a powder, and the porous body 2 is immersed therein. Block-shaped or strip-shaped ones may be supplied.

By this infiltration treatment, the pores 17 of the porous body 2 shown in FIG. 4A are filled with copper or a copper alloy containing Ti, and the porous body 2 is formed by the plurality of metal particles 10 in contact with each other. The metal composite 3 is formed by the core portion 18 formed therein and the base portion 19 composed of the infiltrating material 15 that covers the outer periphery of the core portion 18 and is filled between the plurality of metal particles 10. (FIG. 4). (B)).
Further, as shown in FIG. 5, the metal complex 3 further has an interface portion 21 on which the TiC phase 20 is formed at least a part of the interface between the core portion 18 and the base portion 19.

The TiC phase 20 has a different shape depending on the Ti content in the infiltrating material 15 and the amount of the binder 14 in the porous body 2. In addition to the TiC phase 20 formed so as to be scattered or covered at the interface portion 21, the TiC phase 20 also exists in the base portion 19. It may exist between the metal particles 10. Further, as shown in FIG. 5, carbon 22 may remain in the metal complex 3.

By such infiltration treatment, that is, by contacting copper or a copper alloy containing Ti with the porous body 2, heating and holding the porous body 2, the carbon 22 and Ti remaining on the surface of the metal particles 10 constituting the porous body 2 are formed. By reacting and forming a TiC phase 20 at the interface between the metal particles 10 and copper or a copper alloy, the residue of carbon 22 can be suppressed and the strength of the produced metal composite 3 can be significantly improved.

Further, the surplus organic component may be degreased, but in the present invention, the carbon 22 of the organic component reacts with Ti, so that the degreasing treatment can be omitted. In the normal degreasing treatment, after the porous body 2 is produced, the heat treatment is performed at about 500 ° C. for about 1 to 24 hours in a vacuum atmosphere. Therefore, if the degreasing treatment is omitted, the work efficiency is improved.

Here, if the average particle size of the metal particles 10 constituting the metal particles 10 is about 1 μm or more and 50 μm or less, the metal particles 10 have high fluidity, so that a uniform metal particle layer is used in the binder injection method. 12 can be formed, and a highly accurate porous body 2 can be obtained.

In order to increase the packing density of the metal particles 10 to obtain a uniform metal particle layer 12, it is preferable that the metal particles 10 have a spherical shape with an aspect ratio of 1.0, but the aspect ratio is 1.0 or more. It may be a flat shape such as a spherical shape, an elliptical shape, or a polyhedron shape of 0 or less.

Further, since it is difficult for the metal particles 10 having an average particle size of less than 1 μm to form a uniform metal particle layer 12 with low fluidity as it is, these metal particles 10 are mixed with a resin or an organic solvent in advance. It can be used with improved fluidity as a composite particle or dispersion having an average particle size of 1 μm or more and 50 μm or less.

Further, in the present embodiment, SUS316L powder having an average particle size of 10 μm is used as the stainless steel powder which is the metal particles 10, but it can also be applied to other metal particles showing similar fluidity.

Further, the infiltration treatment can be performed in a non-hydrogen atmosphere, but it is preferably in a reducing atmosphere so as not to oxidize carbon. The heating temperature and heating time of the infiltration treatment are, for example, 1100 ° C. and 30 minutes.

Further, the binder 1 may have a hollow structure. At this time, a hole for removal may be provided in advance at the time of forming the binder 1 so that the metal particles 10 that are not bound in the hollow structure can be removed. The removed metal particles 10 can be reused in the three-dimensional modeling apparatus 4.

Further, although an example of manufacturing a fan of a ventilation fan as the metal complex 3 is shown, since the strength of the metal complex 3 can be improved by forming the TiC phase 20, stress is applied to automobile parts, aircraft drive parts, and the like. It can also be applied to metal parts that need to secure the strength.

Further, after the infiltration treatment, the metal complex 3 may be cut or the like to change its shape.

In the present invention, the binding body 1 having a three-dimensional shape is formed by repeating the steps of supplying the organic binder 14 to the layer of the metal particles 10 and binding the metal particles 10 to each other (binding). Body formation process). The binder 1 becomes a porous body 2 having pores 17 by being dried (porous body manufacturing step), and the porous body 2 is impregnated in copper or a copper alloy containing Ti in a reducing atmosphere. It is heated to react carbon 22 of the binder 14 with Ti in copper or a copper alloy.
As a result, a substrate composed of a core portion 18 formed by contacting a plurality of metal particles 10 with each other and a copper or a copper alloy containing Ti that covers the outer periphery of the core portion 18 and is filled between the plurality of metal particles 10. A portion 19 and an interface portion 21 in which the TiC phase 20 is formed at least a part of the interface between the core portion 18 and the base portion 19 are obtained.

Then, the carbon 22 remaining on the surface of the metal particles 10 constituting the porous body 2 and Ti are reacted to form a TiC phase 20 at the interface between the metal particles 10 and copper or a copper alloy, whereby a simple treatment is performed. It is possible to obtain the metal composite 3 whose strength is ensured by the above method.

Embodiment 2.
The strength of the metal complex 3 described in the first embodiment will be described. In order to confirm the strength of the metal complex 3, a metal complex piece having a width of 20 mm, a length of 100 mm, and a thickness of 5 mm was produced in the same manner as in the first embodiment. For comparison, a sample piece infiltrated with copper containing no Ti was prepared.

FIG. 6 is a diagram showing the relationship between the tensile strength ratio of the metal composite piece and the Ti content in the infiltrating material 15, and the tensile strength of the sample piece infiltrated using copper containing no Ti is set to 1, and infiltration is performed. The tensile strength ratio of the metal composite piece when the Ti content of the material 15 is changed is shown.
As shown in FIG. 6, it can be seen that when the Ti content exceeds 0.01% by weight, the tensile strength is higher than that when copper containing no Ti is used. When 0.1% by weight of Ti was contained in the infiltration material 15, the tensile strength ratio became 1.5 times. When the Ti content was further increased, it increased by about 2.5 times at 0.3% by weight, and no increase in tensile strength was observed beyond that. Further, when it exceeded 0.5% by weight, a gradual decrease was observed. When the Ti content was 2.0% by weight or more, there was no difference from the case where copper containing no Ti was used.
It is presumed that this is because Ti formed, for example, titanium hydride and remained on the surface of the metal particles 10 to inhibit the formation of the TiC phase 20. Further, when the Ti content is 2.0% by weight or more, it seems that the TiC phase is less likely to be formed at the interface portion 21.

That is, when the Ti content in the infiltrating material 15 is less than 0.01% by weight, the amount of TiC phase 20 formed in the obtained metal composite piece is not sufficient, and the Ti content is 2.0% by weight or more. In the above case, since the formed TiC phase 20 is difficult to be formed, the Ti content is preferably 0.01% by weight or more and less than 2.0% by weight. Further, 0.01% by weight or more and 0.5% by weight or less, 0.1% by weight or more and 0.5% by weight or less, and 0.3% by weight or more and 0.5% by weight or less are preferable.

By infiltrating the copper or copper alloy containing Ti into the porous body 2 in this way, the carbon 22 remaining on the surface of the metal particles 10 constituting the porous body 2 and Ti are reacted with each other, and the metal particles 10 are formed. By forming the TiC phase 20 at the interface between copper and copper or a copper alloy, the residue of carbon 22 can be suppressed and the strength of the produced metal composite 3 can be significantly improved.

In the present invention, each embodiment can be freely combined, and each embodiment can be appropriately modified or omitted within the scope of the invention.

1 Bound body, 2 Porous body, 3 Metal composite, 4 3D modeling device, 5 Modeling chamber wall,
6 tables, 7 modeling chambers, 8 tanks, 9 metal particle feeders, 10 metal particles,
11 squeegees, 12 metal particle layers, 13 nozzles, 14 binders, 15 wetting materials,
16 heater, 17 vacancies, 18 cores, 19 bases, 20 TiC phase,
21 interface, 22 carbon.

Claims (6)

A layer of metal particles is formed, an organic binder is supplied to the layer of the metal particles to bind the metal particles to each other, and the bonded layers of the metal particles are sequentially laminated to form a binder. And the binding body forming process to form
The process of producing a porous body by drying the binder to produce a porous body having pores, and the process of producing the porous body.
The porous body is infiltrated by heating a copper or copper alloy containing Ti in a reducing atmosphere to react the carbon of the binder with the copper or Ti in the copper alloy, and the metal particles and the copper alloy are reacted. The step of forming a TiC phase at the interface with copper or the copper alloy, and
A method for manufacturing a metal complex. The method for producing a metal composite according to claim 1, wherein the Ti content of copper or a copper alloy containing Ti is 0.01% by weight or more and less than 2.0% by weight. The method for producing a metal complex according to claim 1 or 2, wherein the reducing atmosphere is a hydrogen atmosphere. The method for producing a metal complex according to any one of claims 1 to 3, wherein the average particle size of the metal particles is 1 μm or more and 50 μm or less. The method for producing a metal complex according to any one of claims 1 to 4, wherein the metal particles are stainless steel particles. A core part formed by contacting multiple metal particles with each other,
A base portion made of copper or a copper alloy containing Ti that covers the outer periphery of the core portion and is filled between the plurality of metal particles.
An interface portion in which a TiC phase is formed at least a part of the interface between the core portion and the base portion,
Metal complex with.

Images