TC4钛合金表面铜−氧化石墨烯复合电镀层的组织结构和摩擦磨损性能

Microstructure and friction and wear properties of copper-graphene oxide composite coating electrodeposited on TC4 titanium alloy

采用硫酸盐−氯化物体系在TC4钛合金表面电镀铜−氧化石墨烯(Cu–GO)复合镀层。通过扫描电镜、X射线衍射仪、显微硬度计和划痕仪对比研究了Cu镀层和Cu–GO复合镀层的组织结构、显微硬度及结合强度。通过摩擦磨损试验考察了两种镀层的耐磨性。结果表明,Cu–GO复合镀层组织致密,与基体结合紧密,显微硬度为191.7 HV0.49,与基体的结合强度比Cu镀层更高。在常温下与GCr15钢球对磨时,Cu–GO复合镀层能够为TC4钛合金提供良好的摩擦磨损防护,主要的磨损机制为轻微的犁削磨损和削层磨损。与Cu镀层相比,Cu–GO复合镀层具有更低的摩擦因数,且在相同条件下的磨损率更低,耐磨性更佳。

A copper–graphene oxide(Cu–GO)composite coating was electrodeposited on the surface of TC4 titanium alloy in a sulfate-and-chloride-based bath.The microstructure,microhardness,and adhesion of Cu coating and Cu–GO composite coating were compared using scanning electron microscope,X-ray diffractometer,microhardness meter,and scratch tester.The friction and wear behaviors of the two kinds of coatings were studied.The results showed that Cu–GO composite coating was compact and adhered well to the substrate with a microhardness of 191.7 HV0.49 and higher adhesion to the substrate than Cu coating.When wearing against GCr15 steel ball at room temperature,the Cu–GO composite coating can offer good protection for TC4 titanium alloy.The main wear mechanisms of Cu–GO composite coating are slight plowing wear and delamination wear.As compared with Cu coating,Cu–GO composite coating had a lower friction coefficient and lower wear rate under the same conditions,indicating that it has better wear resistance.