Cr2AlC含量对铜基复合材料摩擦磨损性能的影响

采用冷压-烧结方法制备了含质量分数0%、5%、10%、15%Cr₂AlC的铜基复合材料, 利用光学显微镜、扫描电子显微镜及能谱仪观察并分析复合材料微观组织和微区成分, 使用HVS-1000型显微硬度计和M-2000型摩擦磨损试验机测试复合材料的硬度和摩擦磨损性能, 分析Cr₂AlC质量分数对复合材料硬度、摩擦性能和磨损机理的影响。结果表明:含Cr₂AlC铜基复合材料的相对密度为0.8, Cr₂AlC均匀分布在铜基体上, 有效提高了复合材料的硬度; 随Cr₂AlC质量分数增加, 复合材料摩擦系数先升高后降低, 磨损量先降低后回升, 当Cr₂AlC质量分数为10%时, 复合材料的摩擦系数最大, 磨损量最低, 耐磨性能最佳; 未添加Cr₂AlC的纯铜材料磨损机理以黏滑为主, 含Cr₂AlC铜基复合材料的磨损机理是犁削磨损、剥层磨损和氧化磨损三者的结合。

Effects of Cr2AlC content on friction and wear properties of copper matrix composites

The copper matrix composites with Cr₂AlC in the mass fraction of 0%, 5%, 10%, and 15% were prepared by cold pressing-sintering method.The microstructures and compositions of the composites were studied by optical microscope (OM), scanning electron microscope (SEM), and energy disperse spectroscope (EDS).The hardness and the properties of friction and wear of the composites were tested on HVS-1000 microhardness tester and M-2000 friction and wear tester.The effects of Cr₂AlC contents by mass on the hardness, friction property, and wear mechanism of the composites were analyzed.The results show that, the relative density of copper matrix composites with Cr₂AlC is 0.8, the Cr₂AlC evenly distributes on the copper matrix and effectively improves the composites hardness.With the increase of Cr₂AlC content, the friction coefficient of the composites increases first and then decreases, and the abrasion loss decreases first and then increases.When Cr₂AlC content by mass is 10%, the friction coefficient is the largest, the wear rate is the lowest, and the wear resistance is the best.The wear mechanism of pure copper without Cr₂AlC is mainly stick slip, and the wear form of copper matrix composites with Cr₂AlC is the combination of plough wear, stripping wear, and oxidation wear.