JPS59215437A - Electrical contact material - Google Patents

Abstract

PURPOSE:To obtain an electrical contact material having stable contact resistance and much superior welding resistance by internally oxidizing an alloy material having a specified composition consisting of Cd, Sn, Te, Bi and the balance Ag. CONSTITUTION:This electrical contact material is obtd. by internally oxidizing an alloy material having a composition consisting of, by weight, 10-20% Cd, 0.5-5% Sn, 0.5-5% Te, 0.1-3% Bi and the balance Ag. The composition may further contain 0.01-0.5% Fe group element.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electrical contact materials, particularly A g -CdO
This invention relates to improvements in electrical contact materials comprising:

Electrical contact materials made of Ag-Cd0 are widely used because they have excellent adhesion resistance and stable contact resistance when the contact force and separation force of relays are large.

Recently, as relays have become smaller, contact force and separation force have decreased, contacts have become smaller, and contact gaps have become narrower, resulting in problems with welding resistance. For this reason, there is a demand for electrical contact materials with excellent welding resistance.

The present invention is intended to meet such demands (as a result of intensive research, Ag
An electrical contact material has been discovered that has the same stable contact resistance as the electrical contact material made of -Cd0 and has significantly improved welding resistance.

One of the electrical contact materials of the present invention has Cd 1.0-20% by weight, Sn 0.5-5% by weight, 'l''eo, 5-5
City M%.

13+0.1 to 3% by weight, the balance being Ag, and is internally oxidized.

Another part of the electrical contact material of the present invention, Cd1O to 20% by weight, Sn 0.5 to 5% by weight, TeO,5
-5% by weight, B i 0.1-3% by weight, Fe group elements -io, 01-0.5% by weight, and the remainder Ag, and is internally oxidized.

The reason why the component composition of the electrical contact materials of the present invention is limited as described above is as follows.As is well known, Cd is necessary for maintaining excellent welding resistance and stable contact resistance, and Cd is necessary for maintaining excellent welding resistance and stable contact resistance. If it is less than 20mft%, good welding resistance cannot be obtained, and if it exceeds 20mft%, elements that improve wear resistance are added. uJ. 3 n changes the shape of CaO from spherical to needle-like, and the Sn oxide is f″!!
It is necessary to improve the welding resistance because it has a specific value of 0.5
If the car weight% is less than iA:i, there is no such effect, and if it exceeds 5 car weight%, the 119 compound of Sn will aggregate when the contact is opened and closed, and in terms of contact resistance and temperature ■ 1 clay will become 11"b <, which will be explained later. Since it cannot be suppressed by addition, the amount of insects is 0.5 to 5 f.
He is an IT expert. The oxide is necessary for sublimation drop welding resistance, and if it is less than 0.5%, it has no effect, and if it exceeds 5%, the abrasion resistance deteriorates. 0.5 to 5% by weight is suitable. 13i is a brittle oxide and is easy to separate from IW, so it improves welding resistance when the contact force and separation force are small, and also prevents the Sn molten from agglomerating when the contact is opened and closed, resulting in high contact resistance and temperature rise. It is necessary to prevent this, and if it is less than 0.1 V%, it has no effect, and if it exceeds 3 V%, it will extremely lower the melting point of the alloy, making internal oxidation at high temperatures impossible. 0.1-3% is suitable. l'+" E group elements are added to improve arc resistance and wear resistance.
%mii'IYj teiJ: 'c (D effect? jH
Bq (, if it exceeds 0.5 vehicle volume%, hu 1Qll:
] I Jj'L is i1'Ti < unstable and 7, so 0.
01 to 0.5% by volume is suitable.

Next, an electric contact according to the present invention (made using material A and a conventional electric contact material O'-1) will be explained.

After internally oxidizing the silicon Σ body whose composition is not shown in (1)j in the table below, it is processed through compression, sintering, extrusion, drawing, etc.
Magnetic contact ear 1 material of Examples 1 to 7 and conventional example 1゜2
Electrical contacts) made from material with a fixed contact of diameter 5 mm and thickness of 1 part and diameter 4 + nm, l'7-thickness 1.1, 5
A contact opening/closing test was conducted under the following test conditions with the movable contacts of No. 17 facing each other.

Test condition voltage: AClooV 5011z
Current: Input 408, fixed seat 10Δ negative Direction: 20 times, 7 minutes Opening/closing frequency: 20 times, 7 minutes Number of openings/closing: Until molten shield occurs Contact force: 40g Breaking force: 45g (Right side of the table above) -3- As is clear from the numerical values, the electrical contacts of Examples 1 to 7 have an advantage of /
8. It can be seen that the number of openings and closings until the occurrence of adhesion is increased, and the welding resistance ((bleeding) and contact resistance are equally low, and the fluctuation is also small and stable. The electrical contact consisting of 7?iyu-kizuri contacts 1,1
It can be seen that the electrical contacts are equivalent to or better than the electrical contacts made up of the electrical contacts +, +i:t in Conventional Example 1.2.

Explanation of -1- 11111 Welding IIL is much better, so the conventional Δ
It is an innovative product that can replace the electrical contact +1 material made of g-CdO.

Claims (1)

[Scope of Claims] 1) An electrical contact that is internally oxidized and is made of 10 to 20ffi 1% of Cd, 5 to 5% by weight of SnO, 95 to 5% by weight of Te, BiO, and the balance of 1 to 3 commercially available Ag. material. 2) Cd 10-20mM%, Sn 0.5-5 air mass Te 0.5-5 mass%, Bi 0.1-3% by weight, Fe group element 0.01-0.5% by weight, balance Ag An electrical contact material consisting of and internally oxidized.