JP2000303127A - Metal matrix composite material and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable partial strengthening, to reduce the working time and to reduce the treating cost by composing the subject material of a metal base material and many reinforcement particles having hardness higher than that of the base material and knocked into the base material by projection. SOLUTION: A metal matrix composite material 3 is composed of a metal matrix 2 and many reinforcement particles 1 knocked therein by projection. The metal matrix 2 is suitably composed of light metal. As the material for the reinforcement particles 1, metal, ceramic, or the like, having hardness at ordinary temp. higher than that of the metal matrix 2 is suitable, and the particle size thereof is preferably controlled to <=100 μm. The knocking-in depth of the reinforcement particles 1 is suitably controlled to <=200 μm. The reinforcement particles 1 are knocked into the metal matrix 2 under the projection pressure, preferably, of >=2.5 kgf/cm2 in the air by a projection nozzle 4 to form a layer of the metal matrix composite material 3 on the surface region thereof. The projection angle at this time is preferably set to 30 to 45 degrees.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a metal-based composite material and a method for producing the same.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 62-6759 discloses a method in which a molten metal is jetted out and fine particles of a reinforcing material are sprayed on the molten metal in a state of semi-molten fine particles, and these are supplied onto a mold. It discloses a method for producing a metal-based composite material in which reinforcing material fine particles are dispersed in a base material when they are associated and solidified. However, the method for producing a metal-based composite material disclosed in Japanese Patent Application Laid-Open No. 62-6759 discloses that since the entire material is a composite material, only the surface should be partially cured for wear resistance, corrosion resistance and the like. There is a problem that it is not suitable in some cases. As a local production method of the metal-based composite material, there are thermal spraying, cladding, alloying, CVD, PVD, and the like. However, due to the following problems, it has been practically used only in special applications. .

[0003]

The conventional methods for locally producing metal matrix composites such as thermal spraying, cladding, alloying, CVD, PVD, etc., require a long processing time, require expensive dedicated equipment, and have a high processing cost. , Etc.
An object of the present invention is to provide a metal-based composite material and a method for producing the same, which can be partially strengthened (the local production of the metal-based composite material is possible), the processing time is short, and the processing cost is low.

[0004]

The present invention to achieve the above object is as follows. (1) A metal matrix composite material comprising: a metal base material; and a number of reinforcing particles harder than the metal base material and projected into the metal base material by projection. (2) The metal-based composite material according to (1), wherein the particle size of the reinforcing particles is 100 μm or less, and the depth of implantation of the reinforcing particles is 200 μm or less. (3) The metal-based composite material according to (1), wherein the metal base material is a light metal. (4) A method of manufacturing a metal-based composite material in which a large number of reinforcing material particles harder than the metal base material are injected into the metal base material by projection to manufacture the metal-based composite material. (5) The method for producing a metal-based composite material according to (4), wherein the reinforcing material particles have a particle size of 100 μm or less and the reinforcing material particles are driven into the metal base material at a projection pressure of 2.5 kg / cm ² or more. (6) The method according to (4), wherein the metal base material is a light metal. (7) The reinforcing material particles are placed at a distance of 30 from the surface of the metal base material.
The method for producing a metal-based composite material according to (4), wherein the projection is performed at an angle of up to 45 °. (8) The reinforcing material particles are projected at an angle perpendicular to the surface of the metal base material, and then 30 to 30 degrees from the surface of the metal base material.
The method for producing a metal matrix composite according to (4), wherein the projection is performed at an angle of 45 °. (9) The method for producing a metal-based composite material according to (4), wherein the reinforcing material particles are projected onto the metal base material when the metal base material is at a temperature higher than room temperature and in a solid state. (10) The method for producing a metal-based composite material according to (4), wherein the reinforcing material particles are projected onto the metal base material when the metal base material is at room temperature.

In the method of producing a metal-based composite material of (1) and the method of producing a metal-based composite material of (4), since a large number of reinforcing particles are driven into the metal base material by projection, the projection of the reinforcing particles is performed. By limiting the part to a part of the base material, the base material can be partially strengthened. Also, since the surface hardness can be easily increased in a short time by projection, thermal spraying, cladding,
Compared to conventional methods for locally manufacturing metal-based composite materials such as alloying, CVD, and PVD, it is possible to reduce time, manufacturing cost, and equipment cost. In the method for producing a metal-based composite material according to the above (2) and the method for producing a metal-based composite material according to the above (5), the particle size of the reinforcing material particles is 100 μm or less, the implantation depth is 200 μm or less, or the projection pressure is 2.5 kg / cm. Since it is ² or more, unlike conventional shot blasting, the reinforcing material particles are driven into the surface of the base material, buried, and the metal matrix composite is harder than the base material reinforced by the reinforcing material particles on the surface of the base material. The material can be formed. In the method for producing a metal-based composite material according to the above (3) and the method for producing a metal-based composite material according to the above (6), since the base material is a light metal, the hardness of the surface is increased by driving in reinforcing material particles of a harder material. be able to. When the base material is aluminum and the material of the reinforcing material particles is steel, the hardness of the metal-based composite material due to the driving of the reinforcing material particles is increased by about HV 70 or more compared to the hardness of the base material alone. In the method for producing a metal-based composite material according to the above (7), when the reinforcing material particles are projected while being inclined from the surface of the metal base material, the base metal around the hole when the reinforcing material particles are driven into other reinforcing material particles. By being hit and deforming and flowing, the hole when the reinforcing material particles are driven is closed and the reinforcing material particles are embedded in the base metal. It is preferable to project at an angle of 30 to 45 [deg.] In terms of the implantation depth and the closing of the hole after the reinforcement particles have been implanted. In the method (8) for producing a metal matrix composite material, the reinforcing material particles are projected at a right angle to the surface of the metal base material and then projected at an angle of 30 to 45 ° from the surface of the metal base material. The initial right angle projection can increase the penetration depth of the reinforcement particles, and the later oblique projection can close the implantation hole. In the method for producing a metal matrix composite material according to the above (9), the reinforcing material particles are projected when the metal base material is at a temperature higher than room temperature and in a solid state, so that the reinforcing material particles are easily driven and the reinforcing material is The implantation depth of the particles can be increased. In the method for producing a metal-based composite material according to the above (10), the reinforcing material particles are projected onto the metal base material when the metal base material is at room temperature. However, the reinforcing material particles are formed by appropriately selecting the projection pressure and the like. It can be driven into wood. When the reinforcing material particles are projected, the surface of the base metal increases in temperature and then rapidly cooled, so that the base metal structure becomes finer and the strength is improved in this respect.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Metal-based composite material 3 according to an embodiment of the present invention
As shown in FIG. 1 and FIG. 2, a metal base material 2 and a large number of reinforcing material particles which are harder than the metal base material 2 and are projected onto the metal base material 2 (the reinforcing material particles 1 are injected together with compressed air). 1
And consisting of

The metal base material 2 is made of, for example, a light metal (aluminum, magnesium, etc.), copper, nickel, tin, zinc, or an alloy thereof. Since these metals have relatively low hardness, when they are used for sliding parts (cylinder block bores) or parts rubbed by mating members (piston ring grooves of pistons), the surface part is locally metallized. The present invention can be used to increase the hardness as a basic composite material and to improve wear resistance, slidability, heat resistance, and the like.

The material of the reinforcing material particles 1 may be any material having a hardness higher than that of the metal base material 2 at room temperature, such as a ferrous or non-ferrous metal (high-speed steel, stainless steel, etc.), ceramics, graphite, Oxides (such as alumina) and carbides (such as silicon carbide). The particle size of the reinforcing material particles 1 when the reinforcing material particles 1 are granular and converted into a sphere having the same volume,
It is 100 μm or less, usually 10 to 100 μm.

The implantation depth of the reinforcing material particles 1 (the distance between the portion of the reinforcing material particles 1 farthest from the base material surface and the base material surface) is 200 μm or less. Holes formed when the reinforcing material particles 1 are driven into the metal base material 2 are filled with the base material 2, and the reinforcing material particles 1 are in a state of being dispersed in the metal base material 2. The implantation depth of the reinforcing material particles 1 depends on the softness of the metal base material 2 and the projection pressure of the reinforcement particles 1, and the implantation depth is larger as the metal base material 2 is softer and the projection pressure is higher.

The method of manufacturing a metal-based composite material according to the embodiment of the present invention is different from the method of manufacturing a metal-based composite material 3 by projecting a large number of reinforcing particles 1 harder than the metal base material 2 into the metal base material 2 by projection. Become. The material of the metal base material 2 and the material and the particle size of the reinforcing particles 1 are the same as those described in the metal matrix composite material of the embodiment of the present invention.

[0011] The reinforcing material particles 1 are introduced into a projection nozzle 4 in the atmosphere.
^{More, 2.5kgf / cm 2 (1kgf /} cm 2 is 98
kPa) or higher, preferably about 4.0 kgf
At a projection pressure of not less than / cm ² , the metal base material 2 is driven to form a layer of the metal matrix composite material 3 on the surface of the metal base material 2.
This projection pressure is 2.0 kg of the shot blast projection pressure.
higher than f / cm ² . By setting the projection pressure to the above-described projection pressure, the reinforcing material particles 1 can be driven into the metal base material 2. A shot blast machine may be used as the projector, in which case the projection pressure is increased to the above-mentioned projection pressure.

The reinforcing particles 1 are projected from the surface of the metal base material at an angle of θ. By inclining the projection angle from the surface of the metal base material, the metal base material 2 is projected when the reinforcement particles 1 are projected.
The base material 2 around the hole formed in the base material is hit by the subsequent projection particles 1 and caused to flow, so that the hole of the base material 2 can be closed, and the reinforcing material particles 1 are embedded in the base material 2 remote from the base material surface, Can be dispersed. From the surface that closes the hole, the projection angle θ is 30 to
It is desirable to set the angle to 45 °.

From the viewpoint of increasing the projection depth of the reinforcing material particles 1, the projection angle θ is preferably set to 90 ° (perpendicular), so that the reinforcing material particles 1 are formed at an angle perpendicular to the surface of the metal base material 2. And then projecting from the surface of the metal base material at an angle of 30 to 45 ° to fill the hole, it is possible to increase the projection depth and close the hole.

The projection of the reinforcing particles 1 is performed when the metal base material 2 is at a temperature higher than room temperature and in a solid state. The temperature higher than the normal temperature may use residual heat after forming or forging the metal base material 2. By projecting the reinforcement particles 1 at a high temperature, the projection depth of the reinforcement particles 1 can be increased. The projection of the reinforcing material particles 1 may be performed when the metal base material is at room temperature. Even if the metal base material 2 is at room temperature, the reinforcing material particles 1 can be driven into the metal base material 2 by increasing the projection pressure.

The hardness of the metal matrix composite material 3 formed by the above-described manufacturing method is about HV200, and the hardness of the base material matrix alone is about HV130. Therefore, the hardness is increased by about HV70 or more.

[0016]

EXAMPLE A metal particle (matrix material) 2 made of an aluminum alloy (6000 series) was made to collide at a high speed with a reinforcing material particle 1 made of a steel ball of high-speed steel. Projection pressure is 4kgf
// cm ² , and the projection time was about 10 seconds. The projection nozzle diameter was 5 mm, and the projection system was a direct pressure system. The metal structure of the manufactured composite material 3 is shown in FIG. 2 (magnified 800 times). The size of the reinforcing material particles 1 in FIG. 2 is as large as about 30 μm. After drilling a 7 mm hole in the center of a test piece having a diameter of 100 mm and a thickness of 5 to 10 mm produced under the above-described test materials and manufacturing conditions, the sample was attached to a wear tester (taper type) specified in JIS K7204, and a worn wheel was mounted. As a result of performing a rotational wear test under a load of 9.8 N using the composite material of the present invention, the wear amount of the composite material of the present invention was reduced to 1/100 or less compared to the case of using only the matrix material.

[0017]

According to the metal matrix composite material of the first aspect and the method of manufacturing the metal matrix composite material of the fourth aspect, since a large number of reinforcing particles are driven into the metal base material by projection, the reinforcing particles are increased. By limiting the projection part of the base material to a part of the base material, the metal base material can be partially strengthened. Also, since the surface hardness can be easily increased in a short time by projection,
Thermal spraying, cladding,
Compared to conventional methods for locally manufacturing metal-based composite materials such as alloying, CVD, and PVD, it is possible to reduce time, manufacturing cost, and equipment cost. According to the metal-based composite material of claim 2 and the method of manufacturing a metal-based composite material of claim 5, the particle size of the reinforcing material particles is 100 μm or less, the implantation depth is 200 μm or less, or the projection pressure is 2.5 kg / cm. Since it is ² or more, the reinforcing material particles can be driven into and buried in the surface portion of the base material to form a metal-based composite material that is harder than the base material reinforced by the reinforcing material particles in the base material surface portion. . According to the metal matrix composite material of claim 3 and the method of manufacturing the metal matrix composite material of claim 6, since the metal base material is a light metal, the reinforcing material particles of a harder material are injected into the base material surface. A metal-based composite material layer having a higher hardness than the material can be formed. According to the method for producing a metal matrix composite material of claim 7, since the reinforcing particles are projected at an angle of 30 to 45 ° from the surface of the metal base material, the implantation depth can be increased and after the reinforcing particles are driven. The hole can be closed. According to the method for manufacturing a metal matrix composite material of claim 8, the reinforcing material particles are projected at an angle perpendicular to the surface of the metal base material and then at an angle of 30 to 45 ° from the surface of the metal base material. The depth of implantation of the reinforcing particles can be increased by the first right angle projection, and the implantation hole can be closed by the later oblique projection. According to the method for producing a metal matrix composite material according to the ninth aspect, since the reinforcing material particles are projected when the metal base material is at a temperature higher than room temperature and in a solid state, the driving of the reinforcing material particles is facilitated and the reinforcement is performed. The implantation depth of the material particles can be increased. According to the method for producing a metal-based composite material of claim 10, when the metal base material is at room temperature, the reinforcing particles are projected onto the metal base material. It can be driven into the base material. When the reinforcing material particles are projected, the surface of the base metal increases in temperature and then is rapidly cooled, so that the base metal structure becomes finer,
From this point, the strength can be improved.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a metal-based composite material according to an embodiment of the present invention and a side view showing a manufacturing method thereof.

FIG. 2 is a 800 times enlarged metallographic structure of the metal matrix composite material of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reinforcement particle 2 Metal base material 3 Metal matrix composite material 4 Projection nozzle

Claims (10)

[Claims] 1. A metal matrix composite material comprising: a metal base material; and a number of reinforcing particles harder than the metal base material and projected into the metal base material by projection. 2. The metal-based composite material according to claim 1, wherein the particle size of the reinforcing material particles is 100 μm or less, and the implantation depth of the reinforcing material particles is 200 μm or less. 3. The metal-based composite material according to claim 1, wherein the metal base material is a light metal. 4. A method of manufacturing a metal-based composite material, wherein a large number of reinforcing material particles harder than the metal base material are injected into the metal base material by projection to manufacture the metal-based composite material. 5. The method for producing a metal-based composite material according to claim 4, wherein said reinforcing material particles have a particle size of 100 μm or less, and said reinforcing material particles are driven into said metal base material at a projection pressure of 2.5 kg / cm ² or more. . 6. The method according to claim 4, wherein the metal base material is a light metal. 7. The method according to claim 4, wherein the reinforcing particles are projected from the surface of the metal base material at an angle of 30 to 45 °. 8. The metal matrix composite according to claim 4, wherein the reinforcing particles are projected at an angle perpendicular to the surface of the metal base material, and then projected at an angle of 30 to 45 ° from the surface of the metal base material. Manufacturing method. 9. The method according to claim 4, wherein the reinforcing material particles are projected onto the metal base material when the metal base material is in a solid state at a temperature higher than room temperature. 10. The method according to claim 4, wherein the reinforcing material particles are projected onto the metal base material when the metal base material is at room temperature.