Development of W-Cu-Ni Electrical Contact Materials with Enhanced Mechanical Properties by Spark Plasma Sintering Process

This study reports on the development of some W-Cu-Ni materials for use as electrical contacts for low voltage vacuum switching contactors for nominal currents up to 630 A. The contact materials with 85 wt% W, 12-14 wt% Cu and 1-3 wt% Ni were obtained by spark plasma sintering process in vacuum. From very finely dispersed W-Cu-Ni powder mixtures there were produced sintered electrical contact pieces that were investigated in terms of physical, microstructural, mechanical, and functional properties. The material sintered at 1200 degrees C exhibited a near fully dense structure with very low porosity and enhanced mechanical properties: hardness of maximum 480 HV1 and elastic modulus of maximum 220 GPa and low chopping current of maximum 1.77 A.