JPS6360244A - Manufacture of composite material - Google Patents

Abstract

PURPOSE:To manufacture a composite material having sufficient strength against unidirectional and nondirectional stresses, by covering long fibers with whiskers or short fibers to form a mat and then by combining this mat with a metallic matrix. CONSTITUTION:The whiskers or short fibers 5 such as silicon carbide etc., are impregnated with the long fibers 4 such as metal fibers, ceramic fibers, carbon fibers, etc., in a solvent such as water, etc., in a vessel 6, which is dried after the removal of the solvent so as to be formed into a mat 3 in which the long fibers 4 are covered with the whiskers or short fibers 5. Subsequently, the above mat 3 is set in a mold 7, and then the metallic matrix 2 such as molten aluminum, etc., is poured into the above mold 7, which is pressurized to undergo squeeze forging. Thereafter, the resulting molding is taken out and subjected to required finish workings, so that composite material 1 in which strength along the long-fiber 4 direction is increased and strength against nondirectional bending stress and concentrated stress applied to a surface is also improved by means of the whiskers or short fibers 5 can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) This invention relates to a method for manufacturing a composite material formed by embedding fibers in a metal matrix.

(Prior Art) Composite materials in which a metal matrix is reinforced with various fibers such as long fibers, short fibers, or whiskers have recently been known.

There are advantages and disadvantages in reinforcing with long fibers and reinforcing with short fibers or whiskers. For example, a composite material reinforced with long fibers has sufficient strength in a specific direction, but the strength can be increased sufficiently to withstand bending stress or concentrated stress that is not uniform in direction on the surface of a complex shape. I can't. In addition, composite materials reinforced with short fibers and whiskers are better against bending stress and concentrated stress that are not uniform in direction, contrary to those reinforced with long fibers, but
There was a problem that it did not have great strength against stress in a specific direction.

(Problems to be solved by the invention) This invention was made based on the above circumstances, and its purpose is to not only have sufficient strength against stress in a specific direction, but also to have a shape that is It is an object of the present invention to provide a method for manufacturing a composite material that can have sufficient strength even against stress whose direction is not constant on the surface part, such as in complicated cases.

[Structure of the invention] (Means and effects for solving the problem) This invention has the following features:
Long fibers are wrapped with whiskers or short fibers to form a mat, and this mat is composited with metal. In addition, it has been made possible to combine reinforcement with long fibers and reinforcement with short fibers.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an enlarged cross-sectional view of a ring-shaped composite material 1 made by the manufacturing method of the present invention, and this composite material 1 has a mat 3 embedded in a metal matrix 2. This mat 3
is formed by wrapping long fibers 4 arranged along the circumferential direction of a ring-shaped composite material 1 with whiskers or short fibers 5 such that a portion of these is impregnated into the long fibers 4. Metal fibers, ceramic fibers, carbon fibers, or the like are used as the long fibers 4, and silicon carbide whiskers are used as the whiskers. As the short fibers, the same ones as the long fibers 4 are used, but in that case, the length is sufficiently shorter than the long fibers 4. As shown in FIG. 3(A), the mat 3 is prepared by impregnating the long fibers 4 with whiskers or short fibers 5 in a solvent such as water in a container 6, and then removing the solvent from the container 6, and then After drying for a period of time, it is formed into a predetermined shape, in this example a ring.

When the mat 3 is formed in this way, this mat 3
After setting it in the mold 7 as shown in Fig. 3(B),
Molten aluminum that will become the metal matrix 2 is poured, and then this molten aluminum is pressurized to perform molten metal forging.

After that, the molded product in the mold 7 is taken out and subjected to a predetermined finishing process, resulting in -
The ring-shaped composite material 1 as described above is obtained.

According to the composite material 1 manufactured in this way, the mat 3
is formed by wrapping the long fibers 4 with whiskers or short fibers 5, a part of which is impregnated with the long fibers 4, so the strength of the composite material 1 along this direction is strengthened by the long fibers 4, The whiskers or short fibers 5 strengthen the strength against non-directional bending stress and concentrated stress applied to the surface portion. In addition, when surface processing is performed after molten metal forging, the long fibers 4 wrapped in whiskers or short fibers 5 can be prevented from being cut, so that the reinforcement of strength in a specific direction by the long fibers 4 is impaired. That's not true. Furthermore, by using long fibers 4 together, expensive whiskers or short fibers 5 can be produced.
Since the volume ratio can be lowered, costs can be reduced.

Note that the shape of the composite material 1 according to the present invention is not limited to a ring shape, but may be any shape.

Further, when the mat 3 is formed by wrapping the long fibers 4 with whiskers or short fibers 5, it may or may not be impregnated with a part of the whiskers or short fibers 5 in the long fibers 4.

[Effects of the Invention] As described above, in the present invention, long fibers are wrapped with whiskers or short fibers to form a mat, and this mat is composited with metal. Therefore, not only can a composite material with the advantages of both long fibers and whiskers or short fibers be produced, but also the long fibers wrapped in whiskers or short fibers are cut during surface finishing. The strength reinforcement provided by the long fibers is not impaired.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is an enlarged sectional view of the composite material, FIG. 2 is a partially sectional plan view, and FIGS. 3(A) to 3(C) sequentially show the manufacturing process. FIG. 1... Composite material, 2... Metal matrix, 3...
mat, 4... long fibers, 5... whiskers or short fibers. Applicant's agent Patent attorney Takehiko Suzue I love Seimatama! 1 Male Figure 1 (A) (B) Figure 2 (C) Figure 3

Claims (1)

[Claims] A method for producing a composite material, which is characterized by wrapping long fibers with whiskers or short fibers to form a mat, and combining this mat with metal.