Electrical breakdown characteristic of nanostructured W−Cu contacts materials

Abstract

Nanostructured (NS) W−Cu composite powder was prepared by mechanical alloying (MA), and nanostructured bulk of W−Cu contact material was fabricated by hot press sintering in an electrical vacuum furnace. The microstructure, electric conductivity, hardness and break down voltage of NS W−Cu alloys were measured and compared to those of conventional W−Cu alloys prepared by powder metallurgy. The experimental results show that microstructural refinement and uniformity can improve the breakdown behavior and the electric arc stability of nanostructured W−Cu contacts materials. Also, the nanostructured W−Cu contact material shows the characteristic of spreading electric arcs, which is of benefit to electric arc erosion.

Keywords

nanostructured materials / W−Cu alloy / electrical breakdown

References

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