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为了改善Ti6Al4V合金的摩擦学性能,采用预置NiCrBSiFe复合粉末激光熔覆制备高温耐磨复合涂层,分析了涂层的显微组织,测试了其显微硬度、室温(25℃)及高温(600℃)磨损性能,并分析了其机理.结果表明:复合涂层与钛合金基体为冶金结合,以γ-(Ni,Cr,Fe)固溶体为基体,原位生成的TiC、TiB_2和CrB增强相均匀分布于涂层中,涂层的平均硬度为HV0.5950,约为钛合金基体(HV0.5360)的3倍.室温下,由于涂层具有很高硬度,改善了钛合金表面严重的黏着磨损,涂层表现出优异的耐磨性;高温下,钛合金表面生成氧化膜表现出固体润滑效果,摩擦系数和磨损量均下降,而涂层中基体相硬度下降,磨损表面出现犁沟和破碎磨粒,摩擦系数和磨损率相比室温略有上升,但相比钛合金仍表现出较好的高温耐磨性.
In order to improve the tribological properties of Ti6Al4V alloy, a high temperature wear-resistant composite coating was prepared by laser cladding NiCrBSiFe composite powder. The microstructure of the coating was analyzed and its microhardness, room temperature (25 ℃) and high temperature 600 ℃), and its mechanism was analyzed.The results show that the composite coating and the titanium alloy matrix are metallurgical bonding, and the in-situ formation of TiC, TiB_2 and CrB are enhanced by γ- (Ni, Cr, Fe) Phase homogeneous distribution in the coating, the average hardness of the coating HV0.5950, about three times the titanium alloy substrate (HV0.5360) at room temperature, due to the coating has a high hardness, to improve the titanium alloy surface is serious Adhesive wear, the coating showed excellent wear resistance; high temperature, titanium alloy surface oxide film showed a solid lubrication effect, the friction coefficient and wear loss decreased, while the coating matrix hardness decreased, the wear surface furrows And crushed abrasive, friction coefficient and wear rate increased slightly compared to room temperature, but compared to titanium alloy still showed good high temperature wear resistance.