High-density high-conductivity electrical contact material for vacuum interrupters and method of manufacture
AssigneeWestinghouse Electric Corp.
InventorRobert E. Gainer
Life of this patent
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Abstract
A vacuum interrupter contact is formed of copper and chromium which exhibits high electrical conductivity and a high density of greater than about 95% of the theoretical density of the materials. The copper is the predominant constituent, and a mixture of copper and chromium powder is cold-pressed to form a compact which is then vacuum-sintered at a temperature below the melting point of the copper to achieve the desired high density.
Claims8
A vacuum interrupter contact which exhibits high electrical conductivity, and has a high density of greater than about 95% of the theoretical density, which contact is manufactured by the process consisting of admixing copper and chromium powder wherein the copper is present in an amount of greater than 65 wt.% and up to 90 wt.%, cold pressing the admixed powder to form a compact of high intermediate density, and vacuum-sintering the compact at a temperature below the melting point of the copper to achieve the density of greater than about 95%, without further hot densification.
A method of manufacturing high-density, copper-chromium electrical contacts for vacuum interrupters, which method consists of:
- (a) admixing copper and chromium powder wherein the copper powder is present in an amount of from greater than 65 wt.% up to 90 wt.% of the total;
- (b) cold pressing the admixed powders to form a high density compact;
- (c) vacuum-sintering the compact at a temperature below the melting point of copper to achieve a density greater than about 97% of theoretical for the resultant contact, without further hot densification.
Dependencies are inferred from the claim text.