JPS60115359A - Production of composite material - Google Patents

Abstract

PURPOSE:To prevent displacement of a porous body and to produce a desired composite material without chipping, etc. of the porous body by disposing a perforated holding element on the porous body, detaining the element at the circumferential edge thereof to the inside wall surface of a casting mold and pouring the molten metal into the mold. CONSTITUTION:A compression molding 5 consisting of a porous body is preheated and is disposed in a casting mold 7. A holding plate 8 is disposed on the molding 5 and the circumferential edge thereof is press-fitted into the inside wall surface 9 of the mold 7 to fix the plate 8. A molten metal 10 is then poured into the casting mold and is pressurized by a plunger 11 to move a part of the metal 10 toward the part below the plate 8. The pressurizing state is maintained until the molten metal solidifies thoroughly. The solidified body is taken out of the inside of the mold 7 by means of a knock-out pin 12 after thorough solidification of the molten metal.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to composite materials, and more particularly to a method for manufacturing composite materials by pressure casting.

Prior Art One of the methods for manufacturing composite materials in which a matrix metal such as an aluminum alloy is compositely reinforced with reinforcing materials such as various inorganic fibers and ceramic particles is to form a porous body made of the reinforcing material, and to A so-called pressure casting method is known in which a metal body is placed in a mold, molten matrix metal is poured into the mold, and the molten metal is solidified while being pressurized.

In the method for manufacturing composite materials using such pressure casting method,
Since the apparent specific gravity of the porous material is much smaller than the specific gravity of the molten matrix metal, if the porous material is placed in a mold and then the molten matrix metal is poured into the mold, the flow effect of the molten metal will increase. Due to the difference in specific gravity between the porous body and the molten metal, the porous body may float or tilt, making it impossible to form a composite material at a predetermined position within the mold, or the porous body may float or tilt. If the body hits the inner wall surface of the mold or the surface of the plunger, and the porous body is a compression molded body of reinforcing material particles, the compression molded body is damaged, and the porous body is a molded body of reinforcing fibers. In some cases, problems such as the orientation of the reinforcing fibers may be impaired. This problem arises when manufacturing a composite material member in which only a predetermined region is reinforced with a reinforcing material, or when manufacturing a porous material so that the molten matrix metal can penetrate well into the interior from the entire circumference of the porous body. This is especially true when the porous body is placed in a mold that has a volume much larger than the volume of the body.

In addition, in order to avoid such problems, if a porous body made of reinforcing material is fixed directly to the inner wall surface of a mold by press-fitting, etc., not only will the permeability of the matrix metal deteriorate, but also the porous body will come into contact with the mold. This causes problems such as crushing of the exposed parts and cracking of the porous body.

Purpose of the Invention The present invention has been made in view of the above-mentioned problems in the method for manufacturing composite materials by pressure casting, and an object of the present invention is to provide an improved method for manufacturing composite materials so that such problems do not occur. There is.

According to the present invention, the present invention provides a method for manufacturing a composite material comprising a reinforcing material and a matrix metal, including forming a porous body made of the reinforcing material, and placing the porous body in the mold. a perforated holding element is placed on the porous body in contact with the porous body, the perforated holding element is locked to the inner wall surface of the mold at its peripheral edge, and the matrix metal is placed in the mold. This is achieved by a method for manufacturing a composite material in which a molten metal is poured and the molten metal is solidified while being pressurized.

Functions and Effects of the Invention According to the present invention, the porous body disposed in the mold is displaced relative to the mold by the perforated holding element that abuts against it and is locked to the inner wall surface of the mold at the peripheral edge. Therefore, even if the specific gravity of the porous body and the specific gravity of the molten matrix metal differ greatly, or if the molten matrix metal is introduced into the mold with force,
When the molten matrix metal is poured into the mold, the porous body does not float or tilt within the mold, and as a result, the porous body can be placed in the specified position within the mold without causing damage to the porous body. Desired composite materials can be manufactured in the range of .

The porous retaining element used in the method for producing a composite material according to the present invention has sufficient porosity to allow the molten matrix metal to pass through it, and to prevent the molten matrix metal from acting on the porous body. It is preferably made of a material that has the strength to hold the porous body in a predetermined position against flow forces and buoyancy forces, and has a much higher melting point than the matrix metal, such as It may be a wire mesh, a perforated metal plate, a molded body of various inorganic short fibers, or the like.

In addition, in the method for manufacturing a composite material according to the present invention, the porous body is prepared so that the molten metal of the matrix metal can penetrate well into the porous body, and the adhesion between each fine reinforcing material and the matrix metal is improved. Alternatively, before the fine reinforcement aggregate is placed in the mold, it is preferred that the porous body or aggregate is preheated to a temperature above room temperature, preferably above the melting point of the matrix metal.

Example 1 First, as shown in FIG. 1, a compression molding mold consisting of a mold body 2 having a cylindrical hole 1, an upper punch 3 and a lower punch 4 that fit into the hole 1 was prepared. Next, as shown in FIG. 1, alumina particles of 22',io with an average particle diameter of 5μ- and an inorganic binder are placed in the cylindrical depression 5 defined by the mold body 2 and the lower punch 4. Filled with a mixture of colloidal silica and 1. By fitting the upper punch 3 into the hole 1 and pressing the upper punch 3 and the lower punch 4 toward each other using a press device (not shown), the bulk density is 1.75 (1/cc). Diameter 40mm,
A cylindrical compression molded body 5 having a length of 30+nm was formed.

Next, although not shown in the figure, after drying the compression molded product 5, the compression molded product 5 is preheated to 800° C. in the atmosphere, and then the compression molded product 5 is heated as shown in FIG. 300
The mold was placed in a mold 7 at .

Next, a wire mesh (opening size 21 + 11. Wire diameter 1 mm) made of stainless steel (JIS standard 5 LIS304)
The outer edge is made of stainless steel (JIs) with a diameter of 3 mm.
Diameter 4 reinforced with a ring of standard 5IJS304)
A 2 mm retainer plate 8 was placed on the compression molded body 6, and its peripheral edge was press-fitted into the inner wall surface 9 of the mold 7, thereby fixing the retainer plate.

Next, as shown in FIG. 3, a 56-QQcc molten metal 10 of pure zinc (purity 99.3%) at a temperature of 500 DEG C. was poured into the mold. In this case, the pure zinc molten metal 10 remained placed on the holding plate 8 due to its surface tension. Next, as shown in FIG. 4, pure zinc molten metal 10
was pressurized at a pressure of 1500 kc+/♂ by the plunger 11, a part of the molten metal 10 was moved below the holding plate 8, and the pressurized state was maintained until the molten metal completely solidified.

After the molten metal was completely solidified, the solidified material was removed from the mold 7 using the knockout bottle 12. When the solidified body was cut along the axis, a particle-dispersed composite material made of pure zinc reinforced with alumina particles was formed at a predetermined position below the retaining plate 8, and the compression molded body was damaged. No other defects were observed.

In addition, in the composite material formed as described above, alumina particles are uniformly distributed in the matrix of pure zinc.
Adhesion between the alumina particles and the pure zinc matrix was also good.

Example 2 Length 301! lI alumina fiber 13 (fiber diameter 20 μm
1 DuPont 111FP fibers) are oriented in one direction and bundled so that the volume ratio is 50%, and by fixing this with colloidal silica as an inorganic binder, a cylindrical m with a diameter of 40fflI111 and a length of 30IIlli is made.
A molded body 14 was formed. Next, although not shown in the figure, after drying the fiber molded body 14, the fiber molded body 14 is preheated to 800° C. in the atmosphere, and then, as shown in FIG. The mold 15 (mold temperature: 250° C.) was placed in a molding chamber 151) having a molding chamber 151).

Next, a holding plate 16 made of carbon steel (JIS standard 515C) with a diameter of 60 mm and a thickness of 21+1111 is placed on the bottom wall of the pressurizing chamber 15a in contact with the upper end of the fiber molded body 14, and its peripheral edge is The holding plate 16 was fixed by being press-fitted into the inner wall surface of the pressurizing chamber 15a. In this case, as shown in FIG.
It had nine holes 16a of I11.

Next, as shown in FIG. 7, the pressurizing chamber 1 of the mold 15 is
5a and molding chamber 15b, 500 cc of molten metal 17 of aluminum alloy (LJIS standard AC4C) with a temperature of 750° C. was poured into the molding chamber 15b, and the molten metal was heated to 1500 k by plunger 18 as shown in FIG.

A pressure of /al was applied, and the pressurized state was maintained until the molten metal completely solidified. After the molten metal was completely solidified, the solidified material was removed from the mold 15 using a knockout bottle 19. When the solidified body was cut along the axis, it was found that a fiber-reinforced metal composite material made of an aluminum alloy compositely reinforced with alumina fibers was formed at a predetermined position in the molding chamber 15b below the holding plate 16. It was found that the alumina fibers were well oriented in one direction along the axis, and that the adhesion between the alumina fibers and the aluminum alloy matrix was also good.

Example 3 Alumina fiber 20 (fiber diameter 20
DuPont's FP fibers) are oriented in one direction and bundled so that the volume ratio is 50%, and this is fixed with sodium silicate as an inorganic binder to form the structure shown in Figure 10. As shown, diameter 4Qm
A cylindrical fiber molded body 21 with a length of 60Il111+ was formed. Next, although not shown in the figure, the fiber molded body 2
After drying the fiber molded body 21 in the atmosphere,
℃, and then, as shown in FIG. 11, a lower mold 22 having a molding chamber 22a and a recess 22b, and a pressurizing chamber 23a that cooperates with the lower mold 22 and communicates with the molding chamber 22a are formed. Upper mold 23 to be defined and mold 24 (mold temperature 300°C)
was prepared, and the fiber molded body 21 was placed in the molding chamber 22a of the lower mold 22 with the mold opened.

Next, a mixture of alumina-silica short fibers oriented in a substantially three-dimensional random manner at a volume fraction of 10% ("Kaowool" manufactured by Isolite Puffcock Fireproof Co., Ltd.) and colloidal silica as an inorganic binder was molded and dried. The retaining plate 25 having a diameter of 80III11 and a thickness of 7IllIIl is placed in the recess 22b of the lower mold 22 in contact with the upper end of the fiber molded body 21, and the upper mold 23 is placed on the lower mold 22. By arranging and clamping the molds, the holding plate 25-10-8 was fixed between the upper mold 23 and the lower mold 22.

Next, as shown in FIG. 12, 600 cc of molten aluminum alloy (JIS standard AC4C) 26 was poured into the pressurizing chamber 23a of the mold 24 at a temperature of 750°C. In this case, the melt field 26 remained stored in the pressurizing chamber 23a on the holding plate 25 due to its surface tension. Then the first
As shown in Fig. 2, the molten metal 26 is heated at 1500 k (J/alt1
! The pressurized state was maintained until the molten metal completely solidified. After the molten metal was completely solidified, the solidified material was removed from the mold 24 using the knockout bottle 28. When the solidified body was cut along the axis, a fiber-reinforced metal composite material made of an aluminum alloy compositely reinforced with alumina fibers was formed at a predetermined position in the molding chamber 22a below the holding plate 25. It was found that the alumina fibers were well oriented in one direction along the axis, and that the adhesion between the alumina fibers and the aluminum alloy matrix was also good.

Example 4 First, a mold identical to the mold 24 used in Example 3 described above (mold temperature 300°C) was prepared, and although not shown in the figure, an average amount of By filling magnesia particles of 37.7a with a particle size of 10 μm, a diameter of 40+nn+ and a length of 601I is formed in the molding chamber 22a.
It was molded into a 1 m column.

Next, a mixture of alumina short fibers (manufactured by ICI Corporation) "Saphir" (manufactured by ICI Corporation) oriented in a substantially three-dimensional random manner at a volume fraction of 10% and loidal silica as an inorganic binder was molded and dried. A retaining plate having a diameter of 80Ill and a thickness of 7+++m is placed in the recess 221) in contact with the upward slope of the molded body of magnesia powder filled in the molding chamber 22a, and the lower mold 22
By placing the upper mold 23 on top of the upper mold 23, the holding plate
and the lower mold 22.

Next, 600 cc was placed in the pressurizing chamber 23a of the mold 24.

1i750℃ aluminum alloy (JIS standard AC4C
) was poured. In this case, the molten aluminum alloy remained stored in the pressurizing chamber 23a on the holding plate due to its surface tension. Next, the molten aluminum alloy was pressurized at a pressure of 150 kg/♂ by the plunger 27, and the pressurized state was maintained until the molten metal completely solidified. After the molten metal was completely solidified, the solidified material was removed from the mold 24 using the knockout bottle 28. When the solidified body was cut along the axis, a particle-dispersed composite material made of aluminum alloy reinforced with magnesia particles was formed at a predetermined position in the molding chamber 22a below the holding plate of the Safir molded body. The magnesia particles do not move into the pressurizing chamber 23a at all, and the magnesia particles are uniformly distributed in the aluminum alloy matrix.
It was also found that the adhesion between the magnesia particles and the aluminum alloy matrix was good. The bulk density of the magnesia particles was 1.25 g/cc.

Although the present invention has been described in detail with reference to several embodiments above, the present invention is not limited to these embodiments, and various embodiments are possible within the scope of the present invention. It will be clear to those skilled in the art that

[Brief explanation of the drawing]

1 to 4 are schematic sectional views showing the manufacturing process of one embodiment of the method for manufacturing a composite material according to the present invention, and FIGS. 5 to 8 are schematic cross-sectional views showing the manufacturing process of another embodiment of the method for manufacturing an alloy according to the present invention. An illustration showing the manufacturing process of one embodiment, FIG. 9 is a plan view showing the retaining plate used in the embodiment shown in FIGS. 5 to 8, and FIGS. 10 to 12 are It is an explanatory view showing the manufacturing process of yet another example of the method for manufacturing a composite material according to the present invention. 1... Hole, 2... Mold body, 3... Upper punch,
4... Lower punch, 5... Compression molded body, 7... Mold, 8... Holding plate, 9... Inner wall surface, 10... Molten metal of pure zinc, 11... Plunger, 12 Knockout pin, 13... Compression molded body, 14... Fiber molded body, 15... Mold, 15a... Pressure chamber, 15b...
・Molding chamber, 16... Holding plate, 16a... Hole, 17.
... Molten aluminum alloy, 18... Plunger,
19... Knockout pin, 20... Alumina fiber, 21... [1 molded body, 22... Lower mold. 14- 22a...molding chamber, 22b...recess, 23...
Upper mold. 23a... Pressurizing chamber, 24... Mold, 25... Holding plate, 26... Molten aluminum alloy, 27... Plunger. 28...Knockout pin Patent applicant Toyota Motor Corporation Representative Patent attorney Masa Akashi 15- Figure 1 Figure 2 Figure 5 Figure 6 Figure 9 Figure 7 Figure 8 Go to Figure 101" 3. 16

Claims (1)

[Claims] A method for producing a composite material made of a reinforcing material and a matrix metal, comprising forming a porous body made of the reinforcing material, placing the porous body in a mold, and abutting the porous body on the porous body. A perforated holding element is arranged, a peripheral edge of the perforated holding element is locked to the inner wall surface of the mold, the molten metal of the matrix metal is poured into the mold, and the molten metal is solidified while being pressurized. Method of manufacturing composite materials.