铜基粉末冶金滑块材料组织及性能研究

Research on Microstructure and Properties of Cu-based Contact Strip Material

采用冷压烧结粉末冶金法制备了铜基受电靴滑块材料。测试了材料的力学性能,用SEM、电滑动磨损试验等方法分析了材料的断口形貌和载流摩擦磨损性能,探讨了其磨损机理。结果表明,该材料的拉伸断裂呈脆性断裂,在非载流条件下,试样的磨损量随着试验载荷的增加而增大;载流条件下,电流产生大量的电弧热促进了石墨的润滑作用;加载10A电流情况下,磨损量随滑动速度的增加先减小后增大;加载30A电流情况下,磨损量随滑动速度的加快而增大。摩擦系数在滑动初始阶段迅速升高,在低速、载流情况下,这一现象更为明显。电流的加入使平稳阶段的摩擦系数相对较低。

A copper graphite composite material was prepared by means of the powder metallurgy method. Me chanical properties were tested by tensile and impact experiments. Fracture surface and wear property of the material were analyzed by scanning electron microscopy（SEM） and electrical wear tests. The results indicate that the brittle fracture is the main mechanism and the wearing capacity increases with the increase of loads. Arc heat from the electric current promotes graphite lubrication carrying electric current. Wear loss reduces firstly and increases afterward with the increase of the slid speed under 10A electric current. Wear loss increases with the increase of the slid speed under 30A electric current. Friction coefficient elevates markedly in the initial sliding phase under low speed and with cur rent. Friction coefficient is low under electrical sliding wear.