A Research on Anode Phenomena Associated with Negative Metal Ion in High-Current Vacuum Arcs

Abstract

Anode phenomena in vacuum arcs are investigated using a cylindrical metal collector surrounding the arc which is generated by a 60 Hz sinusoidal half-wave current (up to 40 kA) in a demauntable vacuum chamber.
Current/voltage characteristics at the collector after anode-spot formation show that positive collector current reverses its direction and floating potential of the collector descends below cathode potential. These findings are attributed to negatively charged carriers flowing from anodic vacuum arc to the collector.
Magnetic mass discrimination between electron and negative metal ion in charge carriers is performed with a circular collector placed in front of a magnetic filter that have a magnetic field strength of about 500 gauss by a pair of permanent magnets. A combined analysis of these studies suggested that a significant amount of negative metal ion is possibly created in the anodic copper vacuum arc.