JPS58210134A - Electrical contact material - Google Patents

Abstract

PURPOSE:To obtain an electrical contact material having improved contact resistance characteristics, welding resistance, etc. by blending Ag with specified amounts of Bi, Cd and In as principal components. CONSTITUTION:This electrical contact material is an internally oxidized electrical contact material consisting of, by weight, 0.1-5% Bi, 1-12% Cd, 5-10% In and the balance Ag or further contg. 0.01-0.5% Fe group element such as Ni. A rivet type electrical contact made of the material having said composition is superior to a conventional contact in contact resistance and welding resistance, and they are almost equal to each other in superior consumption resistance.

Description

[Detailed description of the invention] The present invention relates to electrical contact materials.

Silver-indium oxide has conventionally been used as one of the electrical contact materials manufactured by internal oxidation. Silver-indium oxide has excellent contact properties such as wear resistance and welding resistance, but has the disadvantage that oxides accumulate and contact resistance increases.

Therefore, the inventor of the present invention has conducted intensive studies to develop an electrical contact material having contact resistance characteristics superior to that of this electrical contact material, and has found a satisfactory electrical contact material.

One of the electrical contact materials of the present invention contains 0.1 to 5% by weight of bismuth, 1 to 12% by weight of cadmium, and 5 to 5% by weight of indium.
10% by weight, the balance being silver, and is internally oxidized.

Another electrical contact material of the present invention is bismuth 0.1~
5% by weight of cadmium, 1-12% by weight of cadmium, 5-10% by weight of indium, 0.01-0.5% by weight of iron group elements, and the balance is internally oxidized. It is something.

In the electrical contact material of the present invention, bismuth 0.1-5% by weight, cadmium 1-12% by weight, indium 5-10%
The reason for limiting the weight percentage is that if bismuth is less than 0.1% by weight, there is no effect of promoting internal oxidation, and if cadmium is less than 1% by weight, there is no effect of preventing oxide agglomeration on the contact surface and low contact resistance characteristics cannot be obtained. If the content of cadmium is less than 5% by weight, sufficient adhesion resistance cannot be obtained; if the content exceeds 5% by weight of bismuth, the melting point of the alloy will be too low and internal oxidation at high temperatures will be difficult; if the content exceeds 12% by weight of cadmium, consumption will increase. This is because the withstand voltage deteriorates and the agglomeration of indium oxide containing more than 10% by weight of indium becomes severe and the contact resistance increases. and 0.1-5% by weight of bismuth.

Welding resistance is within the range of 1 to 12% by weight of cadmium and more than 5% by weight and less than 10% by weight of indium.

Abrasion resistance9. An electrical contact material having sufficiently satisfactory contact resistance characteristics can be obtained.

Furthermore, in another one of the electrical contact materials of the present invention, in addition to 0.1-5% by weight of hismuth, 1-12% by weight of cadmium, and 5-10% by weight of indium, 0.01-0.
The reason for adding 5% by weight is that when it is dispersed in an electrical contact material, the resulting uniform and fine dispersion of indium oxide, bismuth oxide and cadmium oxide further reduces consumption due to discharge. ,0.0
This is because if it is less than 1% by weight, indium oxide, bismuth # and cadmium oxide will not be uniformly and finely dispersed, and if it exceeds 0.5% by weight, their segregation will increase.

Next, in order to clarify the effects of the electrical contact material according to the present invention, specific examples and conventional examples will be described.

After melting the materials having the compositions of Examples 1 to 4 shown in the left column of the table below to form atomized powder, the mixture was heated at 600°C, 9 atm,
After internal oxidation for 2 days, this oxidized atomized powder was compressed and sintered, extruded and drawn, then cut and processed into headers to produce a head diameter of 5wm, U height 1 day, leg diameter 2.5+1111.
Fixed contact with leg length 2.5m and head diameter 4tm, UAi
1.1 wm1 leg diameter 2.8 fi, leg length 1.6 m.

A movable contact with a spherical head 5R was obtained.

However, bed-type electrical contacts made using the electrical contact materials of Examples 1 to 4 and rivet-type electrical contacts of the same size made using the materials of the conventional examples shown in the left column of the table below in the same manner as in the examples. When electrical contacts were assembled into a hinge-type relay and a switching test was performed under the test conditions below, the results shown in the right column of the table below were obtained.

Test condition voltage: AClooV 50
Hz current 2 input 40A, steady 10A negative
Load: Resistance Switching frequency: 20 times/min Switching/closing frequency: Contact force until welding occurs = 40 g As is clear from the table above, the electrical contacts made with the electrical contact materials of Examples 1 to 4 and the bent type electrical contacts It can be seen that the contact resistance and welding resistance are superior to that of rivet-type electrical contacts made from contact materials, and the wear resistance is approximately the same.

As detailed above, the electrical contact material of the present invention has contact properties that are superior to those of conventional electrical contact materials in terms of contact resistance and welding resistance. It can be said that it is a thing.

Applicant: Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] 1) 0.1 to 5% by weight of bismuth and 1 to 12% of cadmium
% by weight of indium, 5-10% by weight of indium, and the balance silver, and is internally oxidized. 2) 0.1-5% by weight of bismuth and 1-12% of cadmium
% by weight, 5-10% by weight of indium, and 0.0% by weight of iron group elements.
A material consisting of 01 to 0.5% by weight and the balance silver,
and electrical contact materials that are internally oxidized.