ELECTRICAL CHARACTERISTICS OF NI-AL-CR ALLOY ELECTRODE FOR VACUUM CIRCUIT-BREAKER

Several electrodes were fabricated using Ni3Al-Cr and NiAl-Cr alloys for high withstand-voltage vacuum circuit breakers. The microstructure and basic electrical properties for the electrodes were studied. Cr particles were detected and found to be dispersed homogeneously in these alloys. Ni3Al-Cr and NiAl-Cr electrodes have a high withstand-voltage with a mean value of 110 kV. Further more, the electrodes were found to be comparable in performance to conventional of copper alloys electrodes in their interruption-ability and chopping-current. These Ni-Al-Cr alloys show promise as a practical electrode material for high voltage vacuum circuit breakers.