| 摘要 |
AgCdO based contact elements are replaced in contactors and small circuit breakers with CdO-less type elements which exhibit little burn-off in the arc, a low welding force and minimal heating when carrying continuous current. However, known AgSnO2 contact materials do not have optimum values in all operationally important properties. In these contact materials a more firmly adhering oxide layer occurs as compared with AgCdO. The invention relates to a sintered compound material for electrical contacts, consisting of AgSnO2Bi2O3CuO and containing at least one other metal oxide additive which sublimes below the melting temperature of silver. The SnO2, Bi2O3 and CuO are globularly precipitated in silver material structure zones having a maximum diameter of 200 mu m, and the metal oxide additive is distributed on the surfaces of the boundary regions of these microscopic silver zones.
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