Abstract
Various electrode materials for low surge vacuum circuit breakers which were impregnated with silver-10 mass%Te alloy into the sintered matrices of Co, Fe, Ni, Cr, Fe-50 mass%Co and WC-12 mass%Co were prepared in vacuum.
The microstructures and basic electrical properties for the electrodes have been examined. Silver-10 mass%Te can be impregnated to the Co, Fe, Ni, Fe-Co matrices very well. Defects are not found in these alloys at all.
The maximum chopping current values of the materials are approximately 2∼3 A and the average are in the range of 1∼2 A except (WC-Co)-(Ag-Te).
Especially the chopping currents of Co-(Ag-Te) and (Fe-Co)-(Ag-Te) electrodes are very stable and low even after interruptions.
Further, it has been found that the materials are superior in withstand-voltage and interruption-ability to the conventional electrode (Cu-0.75 mass%Pb).
