JPS5916219A - Electric contact material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a silver-nickel oxide electrical contact material manufactured through an internal oxidation method and a sintering method.

<Prior art and its problems> Conventionally, silver-cadmium oxide based (Ag-
cao series). Electrical contacts made of this material have relatively excellent contact resistance, melt resistance, arc resistance, etc., but on the other hand, they have the potential to cause pollution during the manufacturing process and during use.

Therefore, -silver-tungsten-based, -nickel-based, or silver-graphite-based electrical contact materials have been proposed and used as materials that do not contain cadmium, which causes pollution. The electrical contact is made of the above Ag-Ca in terms of contact resistance and welding resistance.
Since they are inferior to O-based materials and their range of use and conditions of use are limited, improvements have been desired.

<Objective of the Invention> The object of the present invention is to provide an electrical contact material that does not use cadmium, which causes pollution, and has excellent contact resistance, welding resistance, and wear resistance.

<Structure and Effects of the Invention> In order to achieve the above object, an electrical contact material according to the present invention is produced by internally oxidizing an alloy of copper, zinc, and silver, adding nickel to the powder, and sintering the powder. In this case, the composition of the alloy before internal oxidation is 1 to 10 wt% copper, 1 to 6 wt% zinc, and the balance is silver, and the composition of nickel is 2 to 20 wt% with respect to the internally oxidized alloy powder. It is something that The reason why each component composition is limited as described above is as follows.

If Cu is less than 21 wt%, wear resistance is poor and the addition effect is not produced, and if Cu is more than 10 wt%, internal oxidation becomes difficult.

If the Zn content is less than 11 wt%, there is no addition effect, and if the Zn content is more than 6 wt%, internal oxidation becomes difficult, as well as the processability decreases due to the phase opening effect with Zn, making it unsuitable for practical use.

It is added to improve Ni8 welding resistance and abrasion resistance, and if it is less than 2 wt %, it has no effect (if it is more than 1 mWt, the contact resistance becomes high).

As described above, the electrical contact material of the present invention is obtained by melting copper, zinc, and silver having the above composition range to form an alloy, internally oxidizing this alloy, and adding nickel having the above composition range to the powder. It is obtained by sintering and does not use cadmium as in the past, so there is no need to worry about pollution, and it is made from a sintered body to which the metallic nickel element is added to improve welding resistance. Therefore, it has excellent welding resistance compared to the silver-copper oxide zinc monoxide electrical contact material obtained by simply internally oxidizing the above alloy, and has excellent adhesion resistance.
Performance equal to or higher than that of g-CaO-based products is ensured.

<Description of Examples> Silver is alloyed with 5 wt% copper and 4 wt% zinc, and the resulting alloy is milled to 0.05 to 0.1 mm using a crusher such as a stamp mill. crushed into chips.

Next, this pulverized product was internally oxidized for 30 hours at 700 mm in an oxygen WB atmosphere of 0.5 atm, and this was powdered with 7 wt% of metallic nickel powder (10-50μ mesh).
was added and mixed for 24 hours using a ball mill, followed by pressure molding. Next, heating sintering at 700° C. for 2 hours and sizing were alternately repeated in an inert gas atmosphere.

After that, the obtained sintered body was heated to 800''C and formed into a 6φ column using an extruder, and then made into a 3φ wire using a wire drawing machine.Next, A 3φ x 61 piece was cut out from the wire to obtain a sample.

Contact resistance,
The amount of consumption and number of welding were determined to be 111,111. The results are shown in the table below. In addition, in the table, the initial characteristics of Comparative Amount 1 (Ag8B-CdO12) and Comparative Amount 2 (Ag91-Ag6-Zn4 internal oxidation product) measured under the same conditions as a comparative example are listed at the same time.

Test conditions Voltage AO220V Current 5A Load Resistance load Contact force 15 g Opening/closing frequency 30 times/min Opening/closing frequency 500,000 times or less Margin 0 The number of welding is when the welding force is 5B or more, according to the above table υ, The sample is Ag88-C (although the multi-contact resistance is slightly higher than 1012, this difference does not pose a problem in practice.On the other hand, in terms of abrasion resistance and welding resistance, comparative quantity l and comparative quantity 2 and 2 are also extremely excellent, and therefore it can be said that it can be replaced by the Ag-CdO contact material.

Claims (1)

[Claims] (1) An electrical contact material obtained by melting metal materials such as copper, zinc, and silver to form an alloy, internally oxidizing this alloy, adding nickel to the powder, and sintering this, The composition of the above alloy is 1 to 10 W copper, 1 zinc
An electrical contact material characterized in that the composition of nickel is 2 to 20 Wt with respect to the internally oxidized alloy powder, with the balance being silver.