JPH04267013A - Electric contact material and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a low-abrasion electric contact material for practical use by dispersing ceramic grains of Si3N4 in silver. CONSTITUTION:Ti about 10wt.% is dispersed on the surface of ceramic grains of Si3N4, ceramic grains 0.1-20wt.% of Si3N4 dispersed with Ti are mixed with silver and sintered, it is chemically bonded with Ag, the hardness and arc resistance are improved, and the low-abrasion property and sintering property can be improved.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electrical contact materials for relays, switches, etc. used in electrical circuits, and a method for manufacturing the same.

0002

BACKGROUND OF THE INVENTION It has been known that hardness, arc resistance, etc. can be improved by dispersing Si3 N4 ceramic particles in silver.

0003

However, in conventional composite materials in which Si3 N4 ceramic particles are dispersed, densification by sintering is inhibited due to the dispersion of Si3 N4 ceramic particles, and after sintering, Si3
Since the N4 ceramic particles and Ag are not chemically bonded, for example, when Si3 N4 ceramic particles appear on the contact surface, there is a problem that the Si3 N4 ceramic particles fall off from the surface.

[0004] Therefore, relays used in electric circuits,
When used in electrical contact materials such as switches, although the hardness and arc resistance are improved, a sufficient contact life cannot be obtained due to poor wear resistance.

The object of the present invention is to solve the above-mentioned problems and to improve the hardness and arc resistance by dispersing Si3 N4 ceramic particles in Ag, and to create a material with low abrasion that is sufficiently suitable for practical use. The present invention provides electrical contact materials.

[0006]

[Means for solving the problems] The present invention provides a
0% by weight of Si3N4 ceramic particles and 0.0% by weight of Si3N4 ceramic particles.
It is an electrical contact material characterized by containing 1 to 2.0% by weight of Ti as a binder and the balance consisting of silver.
3 N4 ceramic particles and Ti as a binder
After mixing, a diffusion treatment is performed at 800 to 1000°C for 30 minutes or more to form a Ti diffusion layer on the surface of the ceramic particles, and after further mixing with silver, a sintering treatment is performed at 700 to 950°C for 30 minutes or more. A method of manufacturing an electrical contact material is characterized in that:

[0007]

[Operation] The most distinctive feature of the above structure is that Ti is added to 10% by weight of the Si3 N4 ceramic particles.
By including the Si3 N4 ceramic particles to a certain extent, Ag and the Si3 N4 ceramic particles are chemically strongly bonded to each other by Ag-Ti-N-Si bonds. Particles are extremely unlikely to fall off the contact surface.

Furthermore, since adding Ti to Ag improves sinterability, the composite material of the present invention also has improved sinterability.

[0009] Furthermore, the content of ceramic particles of Si3N4 is specified to be 0.1 to 20% by weight, because if it is less than 0.1% by weight, no increase in hardness or improvement in arc resistance will be observed; This is because if it exceeds this, not only the workability decreases but also the abrasion resistance deteriorates significantly.

[0010] The particle size of the Si3 N4 ceramic particles is preferably fine particles of 2 microns or less.

[0011] Examples will be described below to explain the present invention in more detail, but these examples are not intended to limit the present invention.

0012

[Example] Si3 N4 ceramic particles shown in Table 1 and 10% by weight T of the Si3 N4 ceramic particles
After mixing i with a V-type mixer for 1 hour, a diffusion treatment was performed at 850° C. for 1 hour.

Further, Ag shown in Table 1 was mixed and mixed for 1 hour using a V-type mixer. Thereafter, according to powder metallurgy techniques, compression molding of the powder and sintering treatment at 850° C. for 4 hours were repeated to produce a billet.

Next, after hot extrusion, wire drawing, and header processing, the head diameter is 5 mm, the head height is 1 mm, and the leg diameter is 2.5 mm.
, fixed contact with leg length 2.5 mm, head diameter 4 mm, and head height 1.
A movable contact with a spherical head r5mm and a leg diameter of 2.8mm and a leg length of 1.6mm was obtained.

[0015] Then, these rivet contacts were assembled into a hinge type relay and a wear test was conducted under the test conditions shown in Table 2.
The results shown in FIG. 2 were obtained. Further, the conventional example was also tested in the same manner. Incidentally, the steps of the method for manufacturing the electrical contact material of the present invention are shown in FIG.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

Effects of the Invention As is clear from the above explanation, according to the electrical contact material of the present invention, a predetermined amount of Ti is added to Si in Ag.
By dispersing and adding it to 3N4 ceramic particles, it forms a strong chemical bond through Ag-Ti-N-Si bonds, resulting in an electrical contact material with good wear resistance, making it suitable for use in electrical circuits. It can be used for relays, switches, etc.

[Brief explanation of the drawing]

FIG. 1 shows a process diagram of a method for manufacturing an electrical contact material of the present invention.

FIG. 2 is a graph of the wear test results of the example and the conventional example.

Claims (2)

[Claims] Claim 1: 0.1-20% by weight of Si3N4
1. An electrical contact material comprising: ceramic particles; and 0.01 to 2.0% by weight of Ti as a binder, with the balance being silver. [Claim 2] Ceramic particles of Si3 N4;
After mixing Ti as a binder, 800-1000
After performing a diffusion treatment at ℃ for 30 minutes or more to form a Ti diffusion layer on the surface of the ceramic particles and further mixing with silver,
A method for producing an electrical contact material, comprising performing a sintering treatment at ~950°C for 30 minutes or more.