Generation of Plasma by Vacuum Arc with Copper-Chromium Cathode

Vacuum arcs are used in various electrophysical devices. In vacuum circuit breakers, arcs are undesirable but occur frequently as contacts get open, producing an electrode-eroding plasma. The parameters of an arc plasma formed in the electrode gap of a vacuum circuit breaker are largely responsible for its stability and long-term operation, and to lengthen the life time of such devices, their electrodes are made of copper-chromium composites. Here we study the mass-charge state of arc plasmas produced with copper-chromium electrodes under the conditions typical of vacuum circuit breakers.