Abstract:Four kinds of Cu-based composites with different mass ratios of graphite and WS₂ as lubricants were fabricated by hot-pressing method. Electrical sliding wear behaviors of the composites were investigated using a block-on-ring tribometer rubbing against Cu-5%Ag alloy ring. The results demonstrated that 800 °C was the optimum sintering temperature for Cu-graphite-WS₂ dual-lubricant composites to obtain the best comprehensive properties of mechanical strength and lubrication performance. Contact voltage drops of the Cu-based composites increased with increasing the mass ratio of WS₂ to graphite. The Cu-based composite with 20% graphite and 10% WS₂ showed the best wear resistance due to the excellent synergetic lubricating effect of graphite and WS₂. The reasonable addition of WS₂ into the Cu-graphite composite can remarkably improve the wear resistance without much rise of electrical energy loss which provides a novel principle of designing suitable sliding electrical contact materials for industrial applications.

Key words: Cu-based composites; graphite; WS₂; synergetic lubrication; wear rate; contact voltage drop