JPS623862A - Joining method for fiber reinforced metal base composite material - Google Patents

Abstract

PURPOSE:To improve the strength of a joint part by exposing the reinforcing fibers in the joint part from a matrix metal then intersecting the reinforcing fibers and joining the same with a joining material in a molten state. CONSTITUTION:A metallic mold is constituted of a stationary mold 2 on a die base 1 and a vertically movable mobile mold 3. The metrix metal 6 in the joint part of composite materials 5, 5 is eluted away by a caustic soda soln., etc. to expose the reinforcing fibers 7, 7. The composite materials 5, 5 are then set between the mold 2 and the mold 3 to intersect the parts of the fibers 7, 7. The joining material 8 such as molten Al alloy is poured into the space between the mold 3 and a plunger 4 and is pressurized by the prescribed pressure via the plunger 4 so as to be solidified and molded. The material 8 and the metal 6 are thoroughly fused together and the composite material is formed. The strength of the joint part is thus improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for joining fiber-reinforced B-base composite materials (hereinafter simply referred to as composite materials) to each other, or to joining composite materials and other metal materials.

(Technical Background of the Invention) Due to the demand for higher strength of industrial materials due to higher output and higher efficiency of industrial equipment, recently, composite materials in which metal 71~Rix is reinforced with fibers, particles, or whiskers are used. There is.

Conventionally known methods for producing composite materials include infiltration, diffusion bonding, powder metallurgy, and foil metallurgy.

However, since actual elemental parts and structural parts are not simple round rods or flat plate shapes, there are limits to manufacturing using the above manufacturing method. Therefore, it may be possible to form composite materials in the form of round bars or flat plates by mechanical processing or forging, but according to this method! &! This has the disadvantage that the fibers are cut and the overall strength is reduced.

By the way, the above-mentioned infiltration method is a method in which molten metal is infiltrated into a fiber preform, so there is a relatively high degree of freedom in the shape. It is extremely difficult to create uniform fiber arrangement t1, and dimensionally large or irregular fibers are subject to limitations due to the limitations of the pressure infiltration equipment.

In order to solve these problems, it is possible to partially strengthen round bars or flat plate-shaped composite materials by casting them together, or to form composite materials with simple shapes into long or complex shapes by joining them together. Conceivable.

[Problems with back modeling technology]

FIG. 5 shows the cross-sectional shape of the joint of composite materials joined by the conventional method, and shows the matrix metal 101.100 of the composite material 100.100. : 101 is integrally fused by the pressure during molding and has sufficient adhesion strength, but the reinforcing fibers 102, 102 are separated from each other, so the strength of the joint is lower than that of the matrix metal 101, 101.
The strength is less than that proportional to the volume fraction of the composite material, making it impossible to obtain a joint corresponding to the strength of the composite material.

[Purpose of the invention]

The present invention consists of 1. This was devised in view of the above 4S circumstances, and the first objective is a method for joining composite materials that can strengthen the strength of the joint when joining fiber-reinforced metal matrix composite materials with a joining material. The goal is to encourage

[Summary of the invention]

In order to achieve the above object, the present invention removes the matrix metal of the composite material at the joint part to expose the reinforcing fibers, and supplies a molten joining material to the reinforcing fibers, The joint itself becomes a composite material made of the joining material and reinforcing fibers, and the strength of the joint can be strengthened to the extent that it is approximately equal to the strength of the base material.

(Embodiments of the Invention) Hereinafter, an embodiment of the method for joining fiber-reinforced gold FiR-based composite materials according to the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a sectional view of a mold used for joining prismatic composite materials. The mold consists of a fixed mold 2 attached to a die base 1, a movable mold 3 that is moved up and down by a cylinder unit, and a movable mold 3. It consists of a plunger 4 that can be moved up and down by a separate cylinder unit.

To join composite materials 5,5 times using a cutting mold,
Matrix metal 6 (
For example, J156061 aluminum alloy) is eluted and removed with a caustic powder solution, and the reinforcing fibers 7...7 (for example, alumina fibers) are exposed to a culm of 20 mtn.
.

Next, a composite material 5° 5 with exposed reinforcing fibers 7 . . . 7 is set between the fixed mold 2 and the movable mold 3. At this time, the exposed reinforcing fibers M7...7 are positioned below the plunger 4, and each of the reinforcing fibers M7...7 is reinforced! L fibers 7...Make sure that the fibers 7 overlap and intertwine.

After this, the space between the movable mold 3 and the plunger it 4 is injected with a bonding material 8, for example, a molten aluminum alloy infiltration, and the plunger p4 is lowered to receive, for example, 500 kg/cj.
Pressure is applied to solidify and form.

As shown in Fig. 2, the joint structure of the composite materials joined in the above manner is such that the reinforcing m fibers 7...7 overlap,
In the meantime, the bonding material 8 is filled. Here, the bonding material is completely fused with the matrix metal 6 and reinforced with 41I
ff7 to form a composite material.

Next, the results of comparing the tensile strengths of a material made only of JIS 6061 aluminum alloy and a composite material made of JIS 6061 aluminum alloy as a matrix metal and alumina (Al2O2) m fibers as reinforcing fibers are not shown in the table. In addition, regarding the composite material I, both the base material part and the joint part were compared.

〔table〕

As is clear from this table, the tensile strength of the joints joined by the method of the present invention is significantly superior to that of ordinary materials.
It can be seen that the strength is equal to the strength of the base material portion by 1118.

FIG. 3 is a sectional view showing a method of joining pipe-shaped composite materials 15, 15, and the same members as those described above are designated by the same numbers. That is, the matrix metal 6.6 at the joint of the composite material 15.15 is eluted and removed with caustic soda, etc., and then set between the fixed mold 2 and the movable mold 3, and the reinforcing fibers 7...7 are interlaced with each other. . At this time, in order to secure the shape of the inner circumference of the pipe, an insert mold 16 is inserted between the composite materials 15 and 15. This insert type 1
6 is movable left and right by a cylinder unit 1- which is not shown.

Then, with the insert mold 16 inserted, plunge 1
74 is lowered and the joining material 8 such as aluminum alloy is pressed and solidified at a pressure of about 50089/d to obtain a pipe-shaped composite material joined into one piece.

FIG. 4 is a cross-sectional view showing an embodiment in which a part of the bolt as an element part is made of composite material. A heater 23 is embedded therein. A cavity 24 is formed in the fixed mold 22, and a threaded portion 25 is formed on the inner peripheral surface of this cavity 24.

On the other hand, a support 26 that can be raised and lowered faces the upper opening of the cavity 24, and plungers 27 that can also be raised and lowered are closely arranged around this support. A threaded portion 28 is formed on the support 26, and the upper end portion of the composite material 29 is screwed and held by this threaded portion 28.

In the above process, the upper and lower ends of the composite material 29 are left, and the surrounding surface thereof is treated with caustic soda or the like to elute and remove about 2 m of the matrix metal 30, exposing the reinforced region t431 on the surrounding surface, and the composite material in this state is While holding the upper end of the mold 29 with the support 26, the mold 29 is set in the cavity 24 of the fixed mold 22, and the plunger t27 is lowered. Then, the bonding material 32 in the cavity 24 is pressurized, and the reinforcing fibers 31
A bolt is obtained in which the composite material 29 is cast in the bonding material 32.

Here, as the bonding material 32, for example, semi-molten J
156061 aluminum alloy and silicon carbide whiskers are mixed to form a sloppy mixture.

Even in this manner, it is possible to obtain an element component with extremely excellent joint strength.

The above is an example of implementation, and the bonding material is not limited to metal, but may also be plastic, and the bonding method is not limited to infiltration, but diffusion bonding may also be used. good.

(Effects of the Invention) As is clear from the description of the embodiments, according to the present invention, when joining a composite material with another material, the reinforcing fibers at the joint are exposed and the joining material is supplied to this part. As a result, the joint itself becomes a composite material consisting of the joining material and reinforcing fibers, and the strength of the joint can be strengthened to the extent that it is approximately equal to the strength of the base material.Furthermore, it is easy to join composite materials with different matrix metals. , the range of applications is extremely wide.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a mold for implementing the joining method according to the present invention, Fig. 2 is a cross-sectional view of a joint of composite materials joined by the method of the present invention, and Fig. 3 is a cross-sectional view for implementing another embodiment. FIG. 4 is a cross-sectional view of a mold for implementing the joining method according to the second invention, and FIG. 5 is a cross-sectional view of a joint of composite materials joined by a conventional joining method. 2.22...Fixed type, 3...Movable type, 4.27...
・Plunger, 5.15.29...Composite material, 6.3
0...matrix fiber, 7,31...reinforced fiber,
8゜32...Joining material. Applicant's agent Kiyoshi Inomata Figure 1 Figure 4

Claims (1)

[Claims] 1. The reinforcing fibers at the joints of the fiber-reinforced metal matrix composite materials to be joined to each other are exposed from the matrix metal, the exposed reinforcing fibers are crossed with each other, and the joined parts are melted. A method for joining fiber-reinforced metal matrix composite materials, characterized in that a certain joining material is supplied. 2. The matrix metal on at least a portion of the surface of the fiber-reinforced metal matrix composite material is removed to expose the reinforcing fibers, and then the exposed portion is supplied with a bonding material in a molten state to be cast. A method for joining fiber-reinforced metal matrix composite materials.