JPH0831253A - Electric contact material - Google Patents

Abstract

PURPOSE:To provide an electric contact material for a small-sized relay for communication, a small-sized switch, etc., being excellent in adhesion resistance and stable with low contact resistance and excellent in environmental resistance. CONSTITUTION:A very small quantity of at least one kind between Ca and Mg or rare earth element is added to Au or Au alloy. It is to be desired that the Au alloy should be Au-Ag alloy or Au-Pd alloy. It is to be desired that the amount of addition of at least one kind between CA and Mg should be 0.15-1%. It is to be desired that the amount of addition of the rare earth element should be 0.05-1%. For the rare earth element, it is good for at least one kind among La, Ce, Sm, Nd, Eu, and Gd to be added.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electric contacts such as small relays and small switches for communication equipment used in a relatively small current region, and more particularly to an electric contact material for suppressing adhesion at the electric contacts.

[0002]

2. Description of the Related Art Conventionally, electrical contacts such as small relays and small switches for communication equipment used in a relatively small current range generate little arc when opening and closing, so decomposition occurs when oxides or sulfides are generated on the contact surface. The contact resistance becomes unstable. Therefore, due to the environmental resistance and the stability of contact resistance, expensive Au
Au-Ag alloys and Au-Pd alloys mainly containing are used. However, this Au-Ag alloy and Au-Pd
After mounting the electrical contacts of the alloy on the printed circuit board, if ultrasonic cleaning is performed at the time of cleaning the circuit board, slight contact may be applied to the contact parts, which may cause the contacts to become unable to open due to adhesion, or after the relay or switch is assembled. There was a problem that contact vibration occurred due to the vibration during the transportation.

[0003]

Therefore, the present invention provides an electrical contact material such as a small relay for communication equipment, a small switch, etc. which has excellent adhesion resistance, low contact resistance and stability, and excellent environmental resistance. It is what

[0004]

The electrical contact material of the present invention for solving the above-mentioned problems is Au or Au alloy, and C
At least one of a and Mg or a rare earth element is minutely added. In this electrical contact material, Au
The alloy is preferably Au-Ag alloy or Au-Pd alloy. The addition amount of at least one of Ca and Mg is preferably 0.005 to 0.5%. further,
The amount of rare earth element added is preferably 0.05 to 1%. The rare earth elements are La, Ce, Sm, Nd,
At least one of Eu and Gd is preferably added. In the electrical contact material of the present invention, the reason why the addition amount of at least one of Ca and Mg is preferably 0.005 to 0.5% is that the hardness of Au or Au alloy is improved and the adhesion resistance is improved. If it is less than 0.005%, the effect is weak, and if it exceeds 0.5%, alloying due to melting becomes difficult, cracks etc. occur during subsequent plastic working, and contact resistance becomes unstable. Because. The reason why the addition amount of the rare earth element is preferably 0.05 to 1% is because A
This is because the hardness of u or Au alloy is improved and it is effective in improving the adhesion resistance. If it is less than 0.05%, the effect is small, and if it exceeds 1%, cracks etc. occur during plastic working, and contact opening / closing operation. As a result, abrasion powder is generated, the rare earth element contained in the abrasion powder is oxidized, and if it intervenes in the contact portion, the contact resistance becomes high and it becomes unstable.

[0005]

The electrical contact material of the present invention having the above-mentioned composition is A
u, Au-Ag alloy, Au-Pd alloy, and other Au-based material-specific adhesiveness is Ca, Mg, La, Ce, Sm, Nd,
It is effectively suppressed by the action of a rare earth element such as Eu and Gd, and can be maintained without impairing the contact stability of the Au-based material, and further, it does not react with an organic gas and can also maintain environmental resistance. .

[0006]

EXAMPLES Examples and conventional examples of the electrical contact material of the present invention will be described. The electrical contact materials of Examples 1 to 6 and Conventional Examples 1 to 3 having the blending composition ratios shown in the left column of Table 1 below are melt-cast, and then drawn to form a wire, and then rolled to form a tape. After that, it was laminated on a base material of Ag-Pd 60% to form a crossbar contact having a width of 1.0 mm, a height of 0.6 mm and a tension thickness of 0.4 mm. However, these contacts are combined with the same type of contacts facing each other, and the contact force is 15g, and the fine sliding distance is 0.2m.
When a contact test was conducted with m, a vibration frequency of 50 Hz, a vibration time of 5 minutes, and five test units each, the results shown in the right column of Table 1 below were obtained.

[0007]

[Table 1]

As is clear from the results in the right column of Table 1, the electrical contact materials of Conventional Examples 1 to 3 have a low contact resistance and are stable, but have a high adhesion coefficient, and there is a concern that they cannot be separated. On the other hand, it can be seen that the electrical contact materials of Examples 1 to 9 have not only a low contact resistance and stability, but also a significantly low adhesion coefficient and excellent adhesion resistance.

[0009]

As described above, the electric contact material of the present invention has excellent adhesion resistance, low contact resistance and stability, and does not react with organic gas and has excellent environmental resistance. , Can replace electrical contact materials such as for small switches.

Claims (5)

[Claims] 1. An electrical contact material comprising at least one of Ca and Mg or a rare earth element minutely added to Au or an Au alloy. 2. The Au alloy is an Au—Ag alloy or Au—
The electrical contact material according to claim 1, which is a Pd alloy. 3. The addition amount of at least one of Ca and Mg is
It is 0.005-0.5%, Claim 1 or 2 characterized by the above-mentioned.
The described electrical contact material. 4. The electrical contact material according to claim 1, wherein the amount of the rare earth element added is 0.05 to 1%. 5. The rare earth element is La, Ce, Sm, N.
The electrical contact material according to claim 1, 2 or 4, wherein the electrical contact material is at least one of d, Eu, and Gd.