Abstract: An electrical contact for vacuum interrupters of a pressed and sintered composition of copper (60-80 wt %), ferrovanadium alloy (40-100 wt % of the balance) with at least 80 wt % of any remainder consisting of a refractory metal of the group of chromium, vanadium and their compounds. The ferrovanadium alloy comprises 55-85 wt % of vanadium.

Abstract: A brazed joint between a beryllium-base part and a copper-base part comprises a first layer of brazing material in contact with the beryllium-base part. This brazing material is an alloy that just prior to brazing consists essentially of silver and a minor constituent of either: (a) tin in a percentage of 4% to 15% by weight of the alloy, (b) silicon in a percentage of 1% to 5% by weight of the alloy, or (c) indium in a percentage of 6% to 25% by weight of the alloy. Contacting this first layer and brazed thereto is a second layer of a material that just prior to brazing consists essentially of silver. Between the second layer and the copper-base part, there is another brazed connection, which is formed at temperatures exceeding 600.degree. C.

Abstract: A vacuum-type circuit interrupter rated to interrupt currents of 30,000 amperes r.m.s. and highercomprises a pair of separable contacts having arcing portions between which arcs are formed upon disengagement of said contacts. These arcing portions are of a material consisting essentially of beryllium formed from a vacuum-cast ingot that has been subjected to hot working by extrusion to produce a microstructure characterized by grains much smaller on the average than the grains of the as-cast ingot.