TC4合金表面Cu/石墨复合镀层的摩擦磨损行为

采用无氰电镀工艺在TC4合金表面制备了Cu/石墨复合镀层，研究了镀层的组织结构和摩擦磨损行为。结果表明，采用无氰电镀方法能够在TC4合金表面制备出组织致密且与基体结合紧密的Cu/石墨复合镀层，但增加镀层中石墨的含量会降低镀层与基体合金的结合强度，并导致硬度小幅下降。摩擦磨损实验结果表明，Cu/石墨复合镀层具有优良的摩擦磨损防护性能，归因于石墨有效降低了镀层的摩擦系数和磨损率；对镀层磨损形貌、磨损产物和摩擦系数的综合分析结果表明，纯铜镀层的摩擦磨损机制主要为犁削磨损、黏着磨损和剥层磨损，Cu/石墨复合镀层的磨损机制为轻微的削层磨损和疲劳磨损。

Friction and wear behavior of Cu/graphite composite coating electroplated on TC4 alloy

Cu/graphite composite coating was prepared on TC4 alloy by cyanide free electroplating. The wear behavior and wear mechanisms of the coating were investigated. The results show that Cu/graphite composite coatings with compact structure and relatively strong coating/substrate combination can be obtained by cyanide free electroplating on TC4 alloy. However, increasing the graphite content in the coating would reduce the bonding strength between the coating and the substrate, and lead to a small decrease in coating hardness.The wear tests show that Cu/graphite composite coating can protect the TC4 substrate from wear effectively, demonstrated by its much lower friction coefficients and wear rates than both TC4 substrate and the pure copper coating. Based on a comprehensive analysis of the wear morphologies, wear products and friction coefficients of the coatings, the main wear mechanisms of the pure copper coating can be deduced as ploughing wear, adhesion wear and peeling wear, while those of the Cu/graphite composite coating are concluded as slight layer cutting wear and fatigue wear.