JPS58224085A - Production of composite material - Google Patents

Abstract

PURPOSE:To obtain a composite material of base metal and noble metal having high joint strength, by forming a wire rod of the base metal and a belt material of the noble metal by hot press welding to make a composite wire rod of a semicircular section, subjecting two pieces of such wire rods by hot press welding thereby forming a composite wire rod having a circular section. CONSTITUTION:A wire rod 10 of base metal having a semicircular section and a belt material 11 of noble metal are formed by hot press welding to make a composite wire rod 12 of a semicircular section. Two pieces of such wire rods 12 are hot press welded by butting the flat surfaces 13 thereof to each other, thereby making a composite wire rod 14 having a circular section. The wire rod 14 is then formed to a required shape by plastic working.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing composite materials.

Conventionally, in order to make a composite material in which the outer peripheral surface of a base metal wire is coated with a noble metal, a wire 2 made of a base metal is inserted into a pipe 1 made of a noble metal 9 as shown in FIG. 1A, as shown in FIG. This is then repeatedly subjected to wire drawing and diffusion treatment to form a composite wire 3 having the required wire diameter as shown in FIG. The composite material 5 for electrical contacts is formed into a cylindrical cross-sectional shape having a lower center trap globulation 4 as shown in FIG. A composite material 6 for eyeglass frames having a four-sided rectangular cross section was obtained.

However, in the above manufacturing method, since the base metal wire 2 is inserted into the yellow metal pipe 1, the inner diameter of the noble metal pipe 1 is slightly larger than the outer diameter of the base metal wire 2.
When the wire rod 2 is inserted into the pipe 1, a □ rearance occurs. Therefore, pipe l and wire rod 2t are drawn in this state.
fi, the adhesion is extremely poor and the bonding strength is insufficient. For this reason, diffusion treatment is performed each time wire drawing is performed to increase the bonding strength, but the diffusion treatment becomes excessive and the composite wire
The contact performance of the composite material 5 for electrical contacts obtained by forming a diffusion layer on the outer periphery of the composite material 5 was deteriorated, and the composite material 6 for eyeglass frames was brittle.

The present invention has been made to solve such problems.
The present invention aims to provide a method for producing a stable composite material with high bonding strength between a base metal and a noble metal on its outer periphery without performing a diffusion treatment.

The method for producing a composite material of the present invention is to hot press-form a base metal wire lO having a semicircular cross section as shown in FIG. 2a and a noble metal strip 11 shown in FIG. As shown in C, a composite wire 12 with a semicircular cross section is made, and then this composite wire 1
As shown in FIG. 2d, the flat surfaces 13 of two wires are pressed against each other under hot pressure to form a composite wire 14 having a circular cross section.Then, this composite wire 14 is subjected to plastic working to obtain the required shape. Cross-sectional shape 1 For example, as shown in FIGS. 2e and 2f, the composite material 16 for electrical contact is formed into a cylindrical shape having a projection 15 at the center of the lower surface. A composite material 17 for eyeglass frames is obtained.

As described above, the method for producing a composite material of the present invention involves hot pressure welding of a base metal wire 10 and a noble metal strip 11 to produce a composite wire 12 having a semicircular cross section; Since the composite wire rod 14 having a circular cross section is obtained by pressure welding, the base metal and the noble metal are bonded in a completely intimate state, and the bonding strength is high and stable. Therefore, unlike conventional manufacturing methods, diffusion treatment to increase bonding strength is not required, so a diffusion layer is not formed on the composite wire 14, and the composite material 16 for electrical contacts obtained by subsequent molding. This prevents the contact performance from deteriorating and the composite material 17 for glasses 7 from becoming brittle.

Next, in order to clarify the effects of the method for manufacturing a composite material of the present invention, specific examples and conventional examples thereof will be described.

[Example 1] As shown in FIG. 2a (Cu-Ni20 weight% height 0.
A base metal wire 10 with a semicircular cross section of 5 m and a width of 1 j IJ and a second
The thickness of A u −A g 25 wt % shown in the figure is 0
．． 07M9 precious metal strip 11 with a width of 1.5u and 900
℃.

The composite wire 1 is formed by pressure welding in a nitrogen gas atmosphere and has a semicircular cross section with a height of 0.5 Iu and a width of 1 su as shown in FIG.
Next, as shown in Fig. 2d, two of these composite wire rods 12 are brought together by pressing their flat surfaces 13 against each other in a nitrogen gas atmosphere at 900°C to form a circular composite wire rod 14 with a diameter of 1JIJ. Then, this composite wire 14 is drawn to form a 0.05'w height and 0.05' width at the center of the lower surface as shown in FIG. 2e.
Composite material 16 for electricity, gas and liquid points with a hemispherical projection 15 of 1 tur in cross section, a kamabot-shaped cross section with a width of 0.5 m and a height of 0.3 m, and an outer layer of noble metal 11' with a uniform wall thickness of 0.04 mm. I got it.

[Example 2] As shown in Figure 2a, the height of the nickel silver is 0.6 m and the width is 1.211 [
A base metal wire lO with a semicircular cross section of J and a noble metal strip 11 having a thickness of 0.1 m and a width of 1.8 fins as shown in Fig. 2 are welded together at 800°C in a nitrogen gas atmosphere. As shown in FIG. 2C, the outer layer of noble metal material 11' has a semicircular cross section with a height of 0.6 mm and a width of 1.2 u, and the wall thickness of the noble metal material 11' is 0.0 mm.
As shown in Figure 2 (d), the flat surfaces 13 were butted against each other and pressed together in a nitrogen gas atmosphere at 800°C to form a diameter of 1.2 ft. A composite wire 14 of wJl was made, and then this composite wire 14 was drawn and formed into a cross-sectional shape as shown in FIG. 2fK to obtain a composite material for eyeglass frames.

[Conventional example]

A vibrator 1 with an outer diameter of 4.1 w and an inner diameter of 3 u made of 25% by weight of Au-Ag as shown in FIG. 7M
After inserting the wire rod 2 and repeating the wire drawing and diffusion treatment 10 times to form the composite wire 3 with a diameter of 0.4 mm as shown in FIG. d [As shown, a noble metal with a hemispherical cross-sectional projection 4 of height 0.05 am, width 0, and 'l*a in the center of the lower surface, with a width of 0.5 ru and a height of 0.3 mm. Composite material 5'f for electrical contacts with a wall thickness of 1' of 0.0411 J was obtained.

However, the composite materials of these examples and conventional examples were heated at 100 H.
Cut each sample into 100 test samples, chuck each sample with 25 strips on each end, and conduct the test. ・Long distance: 50 m
The state of separation between the noble metal and the base metal upon twisting fracture was investigated by microscopic observation, and the results shown in the table below were obtained.

As is clear from the table above, the bonding strength between the noble metal and base metal of the composite material of the conventional example is low and highly variable and unstable, whereas the bonding strength of the composite material of the example noble metal and base metal is highly variable. It can be seen that is small and stable.

According to the method for producing a composite material of the present invention as described in detail above, it is possible to easily produce a stable composite material with high bonding strength between a base metal and a noble metal on its outer periphery without any diffusion treatment. It has excellent effects.

In addition, in the method for manufacturing a composite material of the present invention, two composite wire rods 12 each having a semicircular cross section are connected to a flat surface 1341. e-c fever ru, EE W L, -c yutsu circular. ,
. Since the wire rod 14 is made, the composite wire rod 12 with a semicircular cross section placed on the side where the glojection 15 will be formed should have a thin outer layer or a base material coated with a material different from the precious metal on the contact surface. This also has the effect of saving precious metals.

[Brief explanation of drawings]

1A to 1E are diagrams showing the steps of a conventional method for manufacturing a composite electrical contact material, and FIGS. 2A to 2F are diagrams showing the steps of the method for manufacturing a composite material of the present invention. 10...Base metal wire, 11...Precious metal strip, 11'...Precious metal, 12...
... Composite wire rod with semicircular cross section, 13 ....7 rat surface, 14 .... Composite wire rod with circular cross section, 15 ...
... Gloziection, 16 ... Composite material. Applicant Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] A base metal wire rod and a precious metal strip are hot pressure welded to form a composite wire rod with a semicircular cross section.Then, these two composite wire rods are hot press welded on a flat surface to form a composite wire rod with a circular cross section. Sakushi,
A method for manufacturing a composite material, which comprises then forming the composite wire into a desired cross-sectional shape by plastic working.