Contact material for vacuum circuit interrupter, contact member of such material, a vacuum circuit interrupter and the use of such material

摘要

A contact material (4,5) for use in a vacuum circuit interrupter which simultaneously provides superior current interrupting performance and a breakdown voltage. The contact material (4,5) of the invention includes components of copper, tantalum and at least one of cobalt and iron. Cobalt or iron should be present in an amount of 50 wt% or less, while the combination of tantalum and cobalt or iron should be present in an amount of at least 10 wt%. A fourth component of at least one of titanium, zirconium and aluminium may be added. Also, there may be included a fifth component containing at least one of a low melting point metal, alloys of a low melting point metal, intermetallic compounds of a low melting point metal, and oxides thereof, with the low melting point metal being at least one of bismuth, tellurium, antimony, thallium, lead, selenium, cerium and calcium in an amount of not more than 20 wt%.