Influence of negative bias voltage on the mechanical and tribological properties of MoS2/Zr composite films

MoS2/Zr composite films were deposited on the cemented carbide YT14 (WC+14%TiC+6%Co) by medium-frequency magnetron sputtered and coupled with multi-arc ion plated techniques. The influence of negative bias voltage on the composite film properties, including adhesion strength, micro-hardness, thickness and tribological properties were investigated. The results showed that proper negative bias voltage could significantly improve the mechanical and tribological properties of composite films. The effects of negative bias voltage on film properties were also put forward. The optimal negative bias voltage was −200 V under this experiment conditions. The obtained composite films were dense, the adhesion strength was about 60 N, the thickness was about 2.4 μm, and the micro-hardness was about 9.0 GPa. The friction coefficient and wear rate was 0.12 and 2.1×10−7 cm3/N·m respectively after 60 m sliding operation against hardened steel under a load of 20 N and a sliding speed of 200 rev·min−1.