TA2合金激光熔覆自润滑复合涂层组织与摩擦学性能

以三种不同质量分数配比为40%Ti–19.5%Ti C–40.5%WS_2、40%Ti–25.2%Ti C–34.8%WS_2、40%Ti–29.4%Ti C–30.6%WS_2的复合粉末为预置原料,采用激光熔覆技术在钛合金TA2表面原位合成自润滑耐磨复合涂层.系统地分析了涂层的物相、组织、显微硬度及其摩擦学性能与机理.结果表明:三种涂层的显微硬度分别为HV_(0.5)927.1、HV_(0.5)1007.5和HV_(0.5)1052.3,相对于基体(HV_(0.5)180)有极大的提高;三种涂层的摩擦系数和磨损率分别为0.41和30.98×10~(–5) mm~3/(N·m);0.30和18.92×10~(–5) mm~3/(N·m)以及0.34和15.98×10~(–5) mm~3/(N·m).WS_2质量分数为34.8%和30.6%的预置粉末制备的涂层表现出较好的耐磨减摩性能,其磨损机理为轻微的塑性变形和黏着磨损.

Microstructure and Tribological Properties of Laser Cladding Self-Lubricating Anti-Wear Composite Coatings on TA2 Alloy

Three different self-lubrication anti-wear composite coatings were fabricated on TA2 titanium alloy by laser cladding with different powder mixtures:40%Ti-19.5%TiC-40.5%WS₂, 40%Ti-25.2%TiC-34.8%WS₂, 40%Ti-29.4%TiC-30.6%WS₂ (w). The microstructure, phase compositions, microhardness and tribological properties of coatings were investigated systematically. The results have demonstrate that the microhardness of the three different coatings were HV_0.5 927.1, HV_0.5 1007.5 and HV_0.5 1052.3, respectively. The microhardness of coatings were improved dramatically compared with the TA2 titanium alloy (HV_0.5 180). The coefficient of friction and the wear rate of those coatings were 0.41 and 30.98×10^-5 mm³/(N·m), 0.30 and 18.92×10^-5 mm³/(N·m), 0.34 and 15.98×10^-5 mm³/(N·m), respectively. The coating fabricated with the powder mixtures of 34.8% and 30.6% WS₂ presented excellent anti-wear and friction reduction properties. The main wear mechanism were mild plastic deformation and adhesive wear.