中文摘要：

以不同含量的MoS2、CaF2为润滑相,加入Cu、Fe和合金等元素,采用粉末冶金烧结工艺制备了具有在室温和高温下均有自润滑作用的铁镍基复合材料。采用UMT-2摩擦磨损试验仪、扫描电镜以及X射线衍射测试并分析了复合材料的摩擦磨损性能以及机理。结果表明,随着MoS2含量的减少、CaF2含量的增加,在室温时摩擦系数、磨损率均增大;而高温时摩擦系数、磨损率先降低后增大。当MoS2、CaF2各含3%（质量百分数）时复合材料在室温和高温时拥有最佳的摩擦性能。该复合材料室温时主要是MoS2起润滑作用,降低材料的摩擦磨损;而高温时MoS2、CaF2与金属相互作用生成CrxSx＋1以及MoO2、CaMoO4、Fe2O3、FeMo4F6等物质,这些物质在摩擦表面形成复合润滑膜而起润滑作用。

英文摘要：

The self-lubricating,Fe-Ni based porous composites with MoS2 and CaF2 mixed in the matrix were prepared by powder metallurgy.The impacts of the contents of MoS2 and CaF2 on the self lubrication of the composites were evaluated.The microstructures of the Fe-Ni based composite were characterized with X-ray diffraction,scanning electron microscopy,and conventional mechanical probes.The results show that the contents of MoS2 and CaF2 significantly affect the tribological properties.For example,as the CaF2 content increased and the MoS2 content decreased,both the wear rate and friction coefficient at room temperature increased;however as the temperature rose up,the wear rate and friction coefficient changed in a decrease-increase mode.The composite,fabricated with MoS2 3%（wt） and CaF2 3%,respectively,displays the optimized tribological property.The possible mechanisms responsible for self-lubrication at different temperatures were also tentatively discussed.