JP2909546B2 - Manufacturing method of metal matrix composite material - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a composite material, and more particularly, to a reinforcing material of inorganic fibers other than metals such as ceramic fibers,
The present invention relates to a method for producing a metal matrix composite material using an aluminum alloy or the like as a matrix.

Problems to be solved by conventional technology and invention For example, sponsored by the Japan Institute of Light Metals, July 15, 1985
Reinforced fibers are continuous fibers, as described in the booklet entitled "Forming Aluminum Composite Materials (FRM)" distributed at the 3rd Metal Forming Seminar held in Atami City on the 16th. As a method for producing a fiber-reinforced metal composite material, there are a diffusion bonding method, a plasma spray method, a vapor deposition method, a melt infiltration method, an electrodeposition method (plating method), and the like. It is known that a method for producing a composite material includes a powder metallurgy method, a component casting method, a molten metal forging method, a semi-solid processing method, an HIP method, and the like.

Particularly when the reinforcing fiber is a discontinuous fiber, the above-described melt forging method (high-pressure casting method) has been generally employed mainly since the above-described method is superior in mass productivity as compared with the other methods described above. ing. However, in the squeeze forging method, it is necessary to press the melt of the matrix metal to a very high pressure, so that the manufacturing equipment becomes large-scale, and therefore, the production of the composite material becomes expensive, which results in the complex This is one of the major obstacles to the practical use of materials.

Thus, in the production of a composite material in the case where the reinforcing fibers are short fibers, it is required to reduce the necessary pressure applied to the molten metal of the matrix metal and further to omit the pressurization. To achieve this, it is necessary to greatly improve the wettability between the reinforcing fibers and the molten metal of the matrix metal.

In view of such a demand, for example, Japanese Patent Application Laid-Open No. 61-295344 proposes to use an aluminum alloy to which a special element is added as a matrix metal. However, there is a problem that sufficient wettability cannot be ensured only by adding a special element to the matrix metal, and that the composition of the matrix metal is limited to a specific one.

Various methods have been proposed for improving the wettability of the matrix metal to the molten metal in the case where the reinforcing fibers are continuous fibers.
JP-A-42504 describes a method in which a metal powder is applied to the surface of a fiber to thereby improve wettability, and is disclosed in JP-A-50-109904, JP-A-52-28433, and JP-A-53-28433. −38791
JP-A-5-176906 and JP-A-57-169037 describe a method of coating the surface of a fiber with a metal to thereby improve the wettability.

As described in these publications, when the reinforcing fibers are continuous fibers, since the fibers are generally oriented in one direction, the molten metal of the matrix metal penetrates between the individual continuous fibers by capillary action, Therefore, according to the method as described above, the wettability between the fiber and the molten metal of the matrix metal can be improved.

However, if the reinforcing fibers are short fibers or whiskers,
Since they are discontinuous, it is impossible to expect the penetration of the molten metal of the matrix metal by capillary action, and therefore, as described in, for example, JP-A-59-205464, the wettability of continuous fibers is improved. Simply applying the method known as a means for causing the fibers to short fibers or whiskers cannot sufficiently improve their wettability. If the reinforcing fibers are whiskers for short fibers,
It is difficult to coat a large amount of these metals or apply a large amount of metal powder, and the cost is very high. These problems are addressed in U.S. Patent Nos. 4,376,803 and 4,569,886.
The same applies to the case where the surface of the fiber is coated with a metal oxide as described in Japanese Patent Application Laid-Open Publication No. H11-209,878.

In addition, Japanese Patent Application Laid-Open No.
As described in JP-A-57-31466 and JP-A-62-67133, a method of preheating a reinforcing material molded body to a predetermined temperature and then infiltrating a molten metal of a matrix metal into the molded body under pressure is known. Are known. According to this method, when the reinforcing material itself is heated to a certain temperature, the wettability of the matrix metal with the molten metal is improved, and the permeability of the molten matrix metal is improved as compared with a case where the molded body is not preheated. I do.
However, in these methods, it is essential to preheat the compact, and special measures are required for these methods. Therefore, these methods are also limited in the efficiency and cost reduction of the production of composite materials. There is.

In addition, Japanese Patent Application Laid-Open No.
As described in JP-A-61-165265, a reinforcing material is utilized by utilizing a redox reaction between a metal oxide contained in a molded product of the reinforcing material and a specific metal element in a matrix metal. There is known a method for improving the permeability of a matrix metal melt into a molded article. However, in this method, there is a problem that a composite material using a metal having an arbitrary composition as a matrix metal cannot be produced because the elements that undergo a redox reaction with each other are limited to some extent.

Furthermore, in any of the above-mentioned conventional methods, it is necessary to pressurize the molten metal of the matrix metal to a certain relatively high pressure. Therefore, in these conventional methods, the pressurization of the molten metal of the matrix metal is omitted. In addition, it is not possible to efficiently and inexpensively produce a composite material by omitting the use of a mold or the like required for pressurization, and to use a relatively large amount of matrix metal in an area other than the molded body in the mold for each casting. However, there is a problem that the yield cannot be improved because solidification of the steel cannot be avoided.

In addition, JP-T-59-500973 and the Journal of Materials Science Letters published in April 1985 state that a molded article of a reinforcing fiber is pretreated with a fluorine-containing reagent, and the molded article is impregnated with a molten metal of a matrix metal. A method for producing a composite material is described. However, in this method, the reinforcing fibers are limited to reinforcing fibers mainly composed of carbon or carbide or surface-coated with carbon or carbide, and the preformed body is preheated before being impregnated with the molten matrix metal. There is a problem that it is necessary to do.

In view of the above-mentioned problems in the conventional method for producing a composite material, the present inventors conducted various experimental studies and found that the reinforcing material was made of an inorganic material other than metal, and was in the form of short fibers, whiskers or particles. It is also found that by mixing fine particles of a specific metal and a specific metal fluoride in a molded body of an inorganic reinforcing material other than a metal, various problems as described above can be solved. .

The present invention is based on the knowledge obtained as a result of various experimental studies performed by the inventors of the present application, and when the reinforcing material is in the form of short fibers, whiskers or particles, the molten metal of the matrix metal is not pressurized. It is another object of the present invention to provide a method for efficiently and inexpensively producing a composite material in which a matrix metal is well filled between individual reinforcements.

Further, the present invention can provide a composite material having a substantially predetermined shape and size very efficiently and without using a mold for pressurizing a molten metal of a matrix metal or a mold for producing a composite material having a predetermined shape. It is an object of the present invention to provide a method that can be manufactured at a very high yield at a low cost.

Means for Solving the Problems The object as described above is, according to the present invention, a reinforcing material made of an inorganic material other than metal, in the form of short fibers, whiskers or particles, and Ni, Fe, Co, Cr, Mn, Cu , Ag, Si, Mg, A
l, Zn, Sn, Pb, Ti, Nb and fine particles of a metal selected from the group consisting of alloys containing these as main components, and K ₂ ZrF ₆ , KA
lF ₄ , K ₂ TiF ₆ , and a fine piece of a metal fluoride selected from the group consisting of CsAlF ₄ to form a substantially homogeneously mixed molded article including at least a part of the molded article. Is Al,
Mg, Al alloy, and a method for producing a metal-based composite material, which is brought into contact with a molten metal of a matrix metal selected from the group consisting of Mg alloys, and wherein the molten metal is penetrated into the molded body without substantially applying pressure, and Ni , Fe, Co, Cr, Mn, Cu, Ag, S
i, Mg, Al, Zn, Sn, Pb, Ti, Nb and forms of short fibers, whiskers or particles made of inorganic materials other than metals coated with a metal selected from the group consisting of alloys containing these as main components a reinforcement forming _{a, K 2 ZrF 6, KAlF 4} , K 2 TiF 6, CsA
a fine piece of a metal fluoride selected from the group consisting of IF ₄ to form a substantially uniformly mixed compact, and at least a portion of the compact is Al, Mg, an Al alloy, as well as
This is achieved by a method for producing a metal-based composite material, which is brought into contact with a molten metal of a matrix metal selected from the group consisting of Mg alloys and penetrates the molten metal into the compact without substantially applying pressure.

According to the method of the present invention, according to the method of the present invention, a reinforcing fiber made of an inorganic material other than metal, in the form of short fibers, whiskers or particles,
Ni, Fe, Co, Cr, Mn, Cu, Ag, Si, Mg, Al, Zn, Sn, P
b, Ti, Nb and a fine piece of a metal selected from the group consisting of alloys containing these as main components (hereinafter referred to as “specific metal”), K ₂ ZrF ₆ , KAlF ₄ , K ₂ TiF ₆ , and CsAlF ₄ A metal fluoride selected from the group consisting of
And a reinforcing material in the form of short fibers, whiskers or particles made of an inorganic substance other than metal coated with a specific metal, A compact is formed which contains the specific metal fluoride micro-pieces and which is substantially uniformly mixed, with at least a portion of the compact being brought into contact with the molten matrix metal. The molten metal penetrates into the compact through a specific metal. Certain metal fluorides remove the matrix metal melt and certain metal oxides to improve the wetting of the melt with the reinforcement. In particular, the above-mentioned specific metal fluoride is superior in removing the oxide film compared to other metal fluorides,
It is also suitable to be used in combination with the above specific metal. Also, the molten metal of the matrix metal and the specific metal generate heat by reacting with each other, and the heat heats the molten metal and the reinforcing material, thereby improving the permeability of the molten metal into the molded body and the wettability of the reinforcing material, As a result, the molten metal of the matrix metal permeates the entire molded body well.

Therefore, according to the method of the present invention, it is not necessary to press the molten matrix metal or control the atmosphere without pressurizing the molten matrix metal or preheating the reinforcing material. No extensive equipment is needed for pressing or controlling the atmosphere, which makes it possible to obtain a composite material in which the matrix metal is well packed between the individual reinforcements, which is much more efficient and less expensive than conventional methods. Can be manufactured.

In addition, according to the method of the present invention, the molten metal of the matrix metal permeates well into the molded body as described above, so that the molded body is formed into a predetermined shape and dimensions, and a part of the molded body is melted in the matrix metal. In this case, the molten matrix metal quickly penetrates into the entire molded body without any excess or shortage, whereby a composite material having a substantially predetermined shape and size is formed. Therefore, the conventional molten metal which requires a mold for pressing the molten metal of the matrix metal and defining a predetermined product shape, and in which a large amount of matrix metal is inevitably solidified in portions other than the composite material in the mold. Compared with a casting method or the like, a composite material having a substantially predetermined shape and dimensions can be manufactured very efficiently and at a low cost with a very high yield.

According to one detailed feature of the present invention, in the method of claim 1 described above, by mixing the reinforcing material, the specific metal fine pieces and the specific metal fluoride fine pieces,
Alternatively, by adhering a fine piece of a specific metal and a fine piece of a specific metal fluoride to the surface of the reinforcing material, a molded article made of these is formed.

According to another detailed feature of the present invention, in the method of the above-mentioned claim 2, mixing a reinforcing material coated with a specific metal with a specific metal fluoride. Or by attaching a specific metal fluoride to the surface of the reinforcing material coated with a metal, a molded body composed of these is formed.

Another further detailed description of the invention is set forth in the following Claim 2.
In the method of the above paragraph, the surface of the reinforcing material is coated with a specific metal, fine pieces of a specific metal fluoride are dispersed in the coating layer, and a molded article is formed using the reinforcing material having such a composite coating layer. It is formed.

According to the results of an experimental study conducted by the inventors of the present application, if a fine piece of a specific metal and a specific metal fluoride is contained in a molded body, the penetration of the molten metal of the matrix metal into the molded body The weight ratio of the specific metal to the reinforcing material is 2% or more, and the weight ratio of the specific metal fluoride fine pieces to the reinforcing material is 0.03% or more, particularly 0.05% or more. In this case, the molten metal of the matrix metal can be satisfactorily penetrated into the molded body. Thus, according to one particular feature of the invention, the amount of the particular metal in the compact is set at 2% or more by weight to reinforcement,
The amount of the fine pieces of the specific metal fluoride in the molded body is set to 0.03% or more, preferably 0.05% or more in terms of weight ratio to the reinforcing material.

In the production of the metal-based composite material, if the metal fluoride microparticles are contained in the molded body of the reinforcing material, the matrix metal becomes individual compared to the case where the metal fluoride microparticles are not used. While it is possible to produce a composite material that is well infiltrated between the reinforcements, metal fluorides can be produced, for example, K ₂ ZrF ₆ , K _{2
TiF 6, KAlF 4, K 3} AlF 6, K 2 AlF 5 · H 2 O, CsAlF 4, CsAlF 5 ·
Ti, Zr, Hf, which is electrically combined with a positive element such as alkali metal, alkaline earth metal, rare earth metal like H ₂ O,
V, Nb, is preferably a transition metal such as Ta or a fluoride containing Al, particularly a matrix metal is Al, Mg, Al alloy, and a metal selected from the group consisting of Mg alloy,
The metals used with the reinforcement are Ni, Fe, Co, Cr, Mn, C
u, Ag, Si, Mg, Al, Zn, Sn, Pb, Ti, Nb and in the case of a metal selected from the group consisting of these alloys, K ₂ ZrF as shown in the examples below _6, KAlF _4, K ₂ Ti
F ₆ and CsAlF ₄ are preferred. Therefore, the metal fluoride used in the present invention is K ₂ ZrF ₆ , KAlF ₄ , K ₂ TiF ₆ , C ₂
sAlF a metal fluoride selected from the group consisting of _4.

In the production of metal-based composite materials, if the metal is contained in the molded product of the reinforcing material, the composite in which the matrix metal permeates between the individual reinforcing materials better than when no metal is used. Although the material can be manufactured, when the fine pieces of the specific metal fluoride are used in the compact, the metal contained in the compact is Ni, Fe as shown in Examples described later. , Co, Cr, Mn, Cu, Ag, Si, Mg, Al, Zn,
Preferably, the metal is selected from the group consisting of Sn, Pb, Ti, Nb and alloys thereof. Therefore, the metals used in the present invention are Ni, Fe, Co, Cr, Mn, Cu, Ag, Si, M
g, Al, Zn, Sn, Pb, Ti, Nb, and alloys thereof.

Also, according to the results of the experimental research conducted by the inventors of the present application, the reinforcing material, the specific metal, and the specific volume fraction of the fine particles of the metal fluoride in the compact were too high even if the total volume fraction was too low. If it is too long, it becomes difficult to satisfactorily penetrate the molten metal of the matrix metal into the compact. Thus, according to yet another detailed feature of the present invention, the reinforcement in the compact, a particular metal,
And the total volume fraction of the fine pieces of the specific metal fluoride is 5 to 5.
It is set at 80%, preferably 6-80%.

According to the results of an experimental study conducted by the inventors of the present application, even when the volume fraction of a specific metal contained in a molded product is a high value, it is possible to make the molten metal of the matrix metal penetrate well into the molded product. However, as the amount of the specific metal increases, the volume ratio of the reinforcing material relatively decreases, and depending on the type, the composition of the matrix metal greatly changes. Therefore, according to yet another detailed feature of the present invention, the volume fraction of the specific metal in the compact is set to 80% or less, preferably 75% or less.

According to yet another particular feature of the invention, the shaped body has a predetermined shape and dimensions, only a part of which is immersed in the molten matrix metal. According to such a method, a composite material having a predetermined shape and dimensions can be efficiently produced at a very high yield without pressurizing the molten metal of the matrix metal or using a mold or the like for defining a predetermined product shape. It can be manufactured at low cost.

In the method of the present invention, preheating of the compact is unnecessary, but when the compact is preheated in order to improve the wettability of the reinforcing metal and the specific metal with respect to the molten metal of the matrix metal, the temperature of the preform is increased. It is preferable that the temperature is lower than the temperature conventionally used. In the present invention, the form of the fine pieces of the specific metal fluoride may be any form such as short fibers, whiskers, and powder.

Further, Japanese Patent Application No. 63-108172, filed on the same date as the present application by the applicant of the present application, discloses a method for producing a composite material in which metal fluoride fine pieces are mixed into a molded product of a reinforcing material made of metal, Japanese Patent Application No. 63-108168 discloses a method for producing a composite material in which fine metal pieces and fine metal oxide pieces are mixed into a molded product of a reinforcing material.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings with reference to the accompanying drawings.

Example 1 TiC powder (0.3 g) having an average particle diameter of 20 μm and an average fiber diameter of 30
μm, Ni fiber (2 g) with an average fiber length of 1.5 mm and an average particle size of 20
μm of K ₂ ZrF ₆ powder (0.003 g), and pressing the mixture with a mold at a pressure of about 120 kg / cm ² , as shown in FIG. A molded body 10 having a size of 30 × 5 mm was formed. Incidentally, the TiC powder 12
And the volume ratio of the Ni fibers 14 is about 5% and about 15%, respectively, and the weight ratio of the K ₂ ZrF ₆ powder 16 to the TiC powder is about 0.1%, which are substantially uniformly mixed with each other. Was in

Then, as shown in FIG. 2, each preform was immersed for about 10 seconds in a pure Al melt 18 at 750 ° C. for about 10 seconds without preheating each compact without preheating. The melt was taken out of the melt and solidified as it was. In this case, the molten metal remained attached to the molded body due to surface tension until it solidified, and did not substantially drip from the molded body.

After the molten metal was completely solidified and cooled, the dimensions of the solidified body thus obtained were measured, and it was confirmed that the solidified body had substantially the same shape and dimensions as the original compact. . In addition, when this solidified body was cut, its cross section was polished, and observed with an optical microscope, Al had penetrated well into the entire molded body including the portion of the molded body that was not immersed in the molten metal, It was confirmed that a composite material having good adhesion between Ni fibers and TiC particles and Al was formed.

Further, for the purpose of comparison, a molded body similar to the molded body formed in this example was formed except that K ₂ ZrF ₆ powder was not included, and the molded body of this example was used by using the molded body. Production of a composite material was attempted in the same manner as in the case. However, almost no molten aluminum permeated into the molded body, and a composite material could not be produced substantially.

Example 2 Average fiber diameter 10 μm chopped to an average length of 2 mm
Carbon fiber (“Torayca M40” manufactured by Toray Industries, Inc.) (0.14g)
And a Cr fiber with an average fiber diameter of 20 μm and an average fiber length of 1 mm (2.1
g) and KAlF ₄ powder (0.3 g) having an average particle size of 20 μm are wet-mixed, and the mixture is pressed at a pressure of about 120 kg / cm ² using a mold to obtain a 10 × 30 × 5 mm A compact having dimensions was formed. The volume ratios of the carbon fiber and the Cr fiber of this compact were about 5% and about 20%, respectively, and the weight ratio of the KAlF ₄ powder to the carbon fiber was about 11%, which were substantially uniformly mixed with each other. It was in the state that was done.

Then about 1/3 from the lower end without preheating the compact
Was immersed in a melt of an aluminum alloy (JIS standard AC2A) at 750 ° C. for about 10 seconds, after which the molded body was taken out of the melt and solidified as it was. In this case, the molten metal remained attached to the molded body due to surface tension until it solidified, and did not substantially drip from the molded body.

After the molten metal was completely solidified and cooled, the dimensions of the solidified body thus obtained were measured, and it was confirmed that the solidified body had substantially the same shape and dimensions as the original compact. . In addition, when this solidified body was cut, its cross section was polished, and observed with an optical microscope, it was found that the aluminum alloy had penetrated well into the entire molded body including the portion of the molded body that was not immersed in the molten metal. Thus, it was confirmed that a composite material having good adhesion between the carbon fiber and the Cr fiber and the aluminum alloy was formed.

Further, for the purpose of comparison, a molded body similar to the molded body formed in this example was formed except that KAlF ₄ powder was not included, and the molded body was used as in this example. Production of a composite material was attempted in a similar manner. However, the molten aluminum alloy hardly penetrated into the compact, and a composite material could not be produced substantially.

Example 3 Silicon carbide whiskers (85 g) having an average fiber diameter of 1 μm and an average fiber length of 150 μm, and Ni-Cr powder (115
g) and K ₂ TiF ₆ powder (2.5 g) having an average particle diameter of 20 μm are mixed, and the mixture is pressed using a mold at a pressure of about 120 kg / cm ² , as shown in FIG. Diameter as
A cylindrical molded body 20 having dimensions of 90 mm and a length of 40 mm was formed. Incidentally, the silicon carbide whiskers 22 and Ni-Cr
The volume ratio of powder 24 is about 10% and about 10%, respectively, and the weight ratio of K ₂ TiF ₆ powder 26 to silicon carbide whisker is about 3%.
Which were in a substantially homogeneously mixed state with each other.

Next, the molded body is preheated to about 200 ° C, and then the molded body is melted at about 740 ° C with aluminum alloy (JIS standard AC8A).
28 for about 15 seconds, after which the molded body was taken out of the molten metal and solidified as it was. In this case, the molten metal remained attached to the molded body due to surface tension until it solidified, and did not substantially drip from the molded body.

After the molten metal was completely solidified and cooled, the dimensions of the solidified body thus obtained were measured, and it was confirmed that the solidified body had substantially the same shape and dimensions as the original compact. . When the solidified body was cut, the cross section thereof was polished and observed with an optical microscope. The aluminum alloy had penetrated well into the entire formed body without excess or shortage, and the silicon carbide whisker and Ni-Cr powder and aluminum alloy It was confirmed that a composite material having a good adhesion state with the composite material was formed.

Further, for the purpose of comparison, a molded body similar to the molded body formed in this example was formed except that K ₂ TiF ₆ powder was not contained, and the molded body of this example was used by using the molded body. Production of a composite material was attempted in the same manner as in the case. However, the molten aluminum alloy hardly penetrated into the compact, and a composite material could not be produced substantially.

Example 4 An average fiber diameter of 3 μm in which B ₄ C was deposited at a thickness of 0.1 μm,
Alumina fiber with average fiber length 1mm (0.25g) and average particle size 40
μm pure Al powder (2.7 g) and K ₂ Zr ₆ powder (0.075 g) having an average particle size of 30 μm were mixed, and the mixture was mixed using a mold.
10 × 30 × 5mm by pressing at a pressure of 100kg / cm ²
A molded article having the following dimensions was formed. The volume ratios of the alumina fiber and the pure Al powder in this compact were about 5% and about 20%, respectively.
%, And the weight ratio of K ₂ Zr ₆ powder to alumina fiber was about 30%, which were substantially homogeneously mixed with each other.

Next, the molded body was immersed in a pure Mg melt at about 780 ° C. for about 5 seconds without preheating, and then the molded body was taken out of the melt and solidified as it was. In this case, the molten metal remained attached to the molded body due to surface tension until it solidified, and did not substantially drip from the molded body.

After the molten metal was completely solidified and cooled, the dimensions of the solidified body thus obtained were measured, and it was confirmed that this solidified body had substantially the same shape and dimensions as the original molded body . In addition, when this solidified body was cut, its cross section was polished, and observed with an optical microscope, Mg had penetrated well into the entire molded body without excess or shortage, and the adhesion state between the alumina fiber and Mg was good. It was confirmed that a composite material was formed.

Further, for the purpose of comparison, a molded body similar to the molded body formed in this example was formed except that K ₂ Zr ₆ powder was not contained, and the molded body was used in this example. Production of a composite material was attempted in the same manner as in the case. However, almost no Mg melt permeated into the molded product, and a composite material could not be produced substantially.

Example 5 Silicon carbide whiskers (4 g) having an average fiber diameter of 0.5 μm and an average fiber length of 100 μm, and pure Ti powder (5.4 g) having an average particle diameter of 40 μm
And K ₂ TiF ₆ powder (0.6 g) having an average particle size of 30 μm,
The mixture was dispersed in water, the dispersion was vacuum-molded to remove water to some extent, and further compression-molded, and the compact was air-dried to give 20 × 10
A molded body having a size of × 30 mm was formed. Incidentally, respectively approximately 20% volume fraction of silicon carbide whiskers and pure Ti powder of the molded body is about 20%, K ₂ for silicon carbide whiskers
The weight ratio of TiF ₆ powder was about 15%, and they were substantially homogeneously mixed with each other.

Next, the molded body is immersed in a molten aluminum alloy (JIS standard AC4C) at about 650 ° C for about 10 seconds without preheating,
Thereafter, the molded body was taken out of the molten metal, and the molten metal was solidified as it was. In this case, the molten metal remained attached to the molded body due to surface tension until it solidified, and did not substantially drip from the molded body.

After the molten metal was completely solidified and cooled, the dimensions of the solidified body thus obtained were measured, and it was confirmed that the solidified body had substantially the same shape and dimensions as the original compact. . Also, when the solidified body was cut, its cross section was polished, and observed with an optical microscope, the aluminum alloy had penetrated well into the entire molded body without excess or shortage, and the adhesion between the silicon carbide whiskers and the aluminum alloy was also observed. It was confirmed that a good composite material was formed.

Further, for the purpose of comparison, a molded body similar to the molded body formed in this example was formed except that K ₂ TiF ₆ powder was not contained, and the molded body of this example was used by using the molded body. Production of a composite material was attempted in the same manner as in the case. However, the molten aluminum alloy hardly penetrated into the compact, and a composite material could not be produced substantially.

Example 6 Silicon carbide whiskers (21 g) having an average fiber diameter of 1 μm and an average fiber length of 100 μm, an average fiber diameter of 15 μm, and an average fiber length of 1 mm
Stainless steel (JIS standard SUS430) fiber (40g) and KAlF
₄ powder (5g) and water are stirred and mixed, and the mixture is suction molded and dried to have dimensions of 80 × 80 × 10mm, consisting of silicon carbide whisker, stainless steel fiber and KAlF ₄ powder A compact was formed. The volume ratios of the silicon carbide whiskers and the stainless steel fibers of this molded product were about 10% and about 8%, respectively.
lF ₄ powder weight ratio is about 24%, which was substantially a state of being homogeneously mixed with one another.

Next, the molded body is preheated to about 300 ° C., and thereafter, the molded body is fixed to the bottom of the mold by thickening, and the molded body is heated to about 700 ° C. in the mold.
Pour molten aluminum alloy (JIS standard AC4C)
Thereafter, the melt was solidified without applying pressure.

After the molten metal was completely solidified and cooled, the part corresponding to the original molded body was cut out from the solidified body thus obtained, cut and polished, and its cross section was polished and observed with an optical microscope. It was confirmed that the aluminum alloy was well penetrated without excess and deficiency, and that a composite material having a good adhesion between the silicon carbide whisker and the stainless steel fiber and the aluminum alloy was formed.

Further, for the purpose of comparison, a molded body similar to the molded body formed in this example was formed except that KAlF ₄ powder was not included, and the molded body was used as in this example. Production of a composite material was attempted in a similar manner. However, the molten aluminum alloy hardly penetrated into the compact, and a composite material could not be produced substantially.

Example 7 An average fiber diameter of 1 μm on which Ni was deposited at a thickness of about 0.1 μm
m, Si ₃ N ₄ whisker (3.5g) with average fiber length 150μm and K ₂ Zr
Mixing the F ₆ powder (0.4 g), by the mixture pressed at about 150 kg / cm ² pressure using a mold, the outer diameter 85m
A molded body on a ring having a diameter of 70 mm, an inner diameter of 70 mm and a height of 4 mm was formed.
The volume fraction of Si ₃ N ₄ whiskers in this compact was about 15
%, The weight ratio of the K ₂ ZrF ₄ powder to the Si ₃ N ₄ whisker was about 11%, and the whisker and the K ₂ ZrF ₆ powder were substantially uniformly mixed with each other.

Next, the compact is preheated to 200 ° C., and thereafter, the compact 40 is arranged at a position corresponding to the top ring groove of the mold 42 for casting a piston as shown in FIG. A melt of an aluminum alloy (JIS standard AC8A) at about 730 ° C. is poured, and the melt is solidified without substantially applying pressure, thereby obtaining a piston coarse material as shown in FIG.
44 formed.

Then, the piston coarse material thus formed was cut, the cross section thereof was polished and observed with an optical microscope, and it was found that the aluminum alloy had penetrated well into the entire portion corresponding to the original compact, and was thus formed again. No defects such as voids or residual oxide film of the molten aluminum alloy were observed at the interface between the composite material portion and the other aluminum alloy only portion.

Example 8 A silicon carbide fiber having an average fiber diameter of 15 μm and an average fiber length of 2 mm (“Nicalon” manufactured by Nippon Carbon Co., Ltd. was immersed in Ni plating solution in which KAlF ₄ powder having an average particle diameter of 10 μm was suspended.
The surface of each fiber was electrolessly plated with Ni at a thickness of 10 μm.
In this case, the KAlF ₄ powder was dispersed in the Ni plating layer at a volume ratio of about 5%.

Subsequently, the formed silicon carbide fiber was subjected to vacuum forming to form a formed body having a size of 20 × 50 × 10 mm. The volume ratios of the SiC fiber and Ni of this molded product were 10% and 40%, respectively, and KAlF ₄
The weight ratio of the powder was about 6%.

Next, the molded body was immersed in the molten pure Al for 20 seconds without preheating, and then the molded body was taken out of the molten metal and solidified as it was. In this case, the molten metal remained attached to the compact due to surface tension until it solidified, and did not substantially drip off the compact.

After the molten metal was completely solidified and cooled, the dimensions of the solidified body thus obtained were measured, and it was confirmed that the solidified body had substantially the same shape and dimensions as the original compact. . In addition, when this solidified body was cut, its cross section was polished and observed with an optical microscope, Al had penetrated well into the entire molded body without excess or shortage, and the adhesion between the SiC fiber and Al was good. It was confirmed that a certain composite material was formed.

Also, for the purpose of comparison, a molded article similar to the molded article formed in this example was formed except that the fiber was not plated with Ni, and that KAlF ₄ powder was not included, Using the molded body, an attempt was made to manufacture a composite material in the same manner as in this example. However, almost no molten aluminum permeated into the molded body, and a composite material could not be produced substantially.

In Examples 3 to 6 described above, it is possible to produce a composite material having a good composite state by immersing the molded body substantially only in the third part from the lower end in the molten metal of the matrix metal. did it. Further, in each of the above-mentioned examples in which the preform was preheated, a composite material having a good composite state could be produced even when the preform was not preheated. Further, in order to produce a good composite material using the molded articles of the comparative examples of Examples 1 to 6 described above, it
It was found necessary to pressurize to a high pressure of 0-1000 kg / cm ² .

Although not shown as a specific example, CsAl
It has been found that F ₄ is also preferred metal fluoride.

Although the present invention has been described in detail with reference to various embodiments, the present invention is not limited to these embodiments, and various other embodiments are possible within the scope of the present invention. Some will be apparent to those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a compact made of TiC powder as a reinforcing material, Ni fiber and K ₂ ZrF ₆ powder, and FIG. 2 is a diagram showing the compact shown in FIG. FIG. 3 is an exploded view showing a partially immersed state, FIG. 3 is a perspective view showing a columnar compact made of silicon carbide whisker as a reinforcing material, Ni—Cr powder and K ₂ TiF ₆ powder, FIG. FIG. 3 is an illustrative view showing a state in which the molded body shown in FIG. 3 is immersed in a molten metal of a matrix metal, and FIGS. 5 and 6 are illustrative views showing steps of manufacturing a piston coarse material according to the method of the present invention. It is. 10… compact, 12… TiC powder, 14… Ni fiber, 16… K ₂ ZrF ₆ , 18…
Melt of pure Al, 20 ... compact, 22 ... silicon carbide whisker, 24 ... N
i-Cr alloy powder, 26… K ₂ TiF ₆ powder, 28… Molten aluminum alloy, 40… Mold, 42… Mold, 44… Piston coarse material

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takashi Morikawa 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Atsushi Tanaka 1 Toyota Town Toyota City, Aichi Prefecture Inside Toyota Motor Corporation ( 72) Inventor Masahiro Kubo 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Corporation (72) Inventor Tetsuya Nomi 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Corporation (56) References JP 48-311 (JP, A) JP-A-49-42504 (JP, A) JP-A-61-210137 (JP, A)

Claims (2)

(57) [Claims] 1. A reinforcing material made of an inorganic substance other than metal and in the form of short fibers, whiskers or particles, and Ni, Fe, Co, C
r, Mn, Cu, Ag, Si, Mg, Al, Zn, Sn, Pb, Ti, Nb and fine pieces of metal selected from the group consisting of alloys containing these as main components, and K ₂ ZrF ₆ , KAlF _4, K ₂ TiF _6, and a fine piece of metal fluoride selected from the group consisting of CsAlF ₄ these form a substantially homogeneously mixed molded body, the at least a portion of the green body A method for producing a metal matrix composite material in which a molten metal of a matrix metal selected from the group consisting of Al, Mg, an Al alloy, and a Mg alloy is brought into contact with the molten metal, and the molten metal is penetrated into the molded body without substantially applying pressure. 2. Ni, Fe, Co, Cr, Mn, Cu, Ag, Si, Mg, A
l, Zn, Sn, Pb, Ti, Nb and reinforcing materials in the form of short fibers, whiskers or particles made of inorganic materials other than metals coated with a metal selected from the group consisting of alloys containing these as main components And, K ₂ ZrF ₆ , KAlF ₄ , K ₂ TiF ₆ , comprising a fine piece of metal fluoride selected from the group consisting of CsAlF ₄ to form a molded body substantially uniformly mixed with them, At least a part of the compact is contacted with a molten metal of a matrix metal selected from the group consisting of Al, Mg, Al alloy, and Mg alloy, and the molten metal is penetrated into the compact without substantially applying pressure. A method for producing a metal matrix composite material.