Electrical sliding wear properties of Mo-reinforced MoS₂/Cu composites

Abstract

An adequate hardness of MoS₂/Cu composites has not been achieved if these materials are applied under the extreme wear conditions. Therefore, Mo-reinforced MoS₂/Cu composites were prepared by powder metallurgy (P/M) methods. The electrical sliding wear properties in the absence or presence of Mo-reinforced MoS₂/Cu composites were tested by HST-100 high speed electric-tribometer. The hardness, electrical conductivity, density, and microstructure of MoS₂/Cu composites were observed. Mo-reinforcement MoS₂/Cu composites are of good electrical conductivity, while the hardness of Mo-reinforcedment MoS₂/Cu composites is about 33.3% higher than that of MoS₂/Cu composites. With the addition of Mo, composites show better wear properties under high speed and large electric current due to the improvement of hardness. The effects of current intensity and sliding velocity on the wear properties of the tested materials are complicated, and the wear mechanisms of MoS₂/Cu composites are mainly abrasive wear and adhesive wear with arc erosion.

Keywords

mo-reinforced MoS₂/Cu composites / powder metallurgy / electrical sliding wear properties / wear mechanisms

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