中文摘要：

用粉末冶金方法制备Ni-Cr基自润滑复合材料,研究了固体润滑剂MoS_2和石墨对复合材料的机械性能和摩擦学性能的影响。结果表明,随着MoS_2含量的增加,复合材料的显微硬度明显降低;MoS_2添加量从10%（质量分数,下同）增加到15%,复合材料摩擦系数和磨损率的变化并不明显。随着石墨含量的增加,复合材料的显微硬度呈逐渐降低的趋势,在400℃和800℃的摩擦系数呈升高趋势,石墨添加量为10%时室温摩擦系数最小。同时添加5%MoS_2和10%石墨时,复合材料的摩擦系数保持在0.48-0.65,石墨与MoS_2之间存在着协同效应,但是磨损率比添加单一润滑剂时高一个数量级。

英文摘要：

The influences of MoS_2 and graphite on the tribological properties of Ni-Cr based self-lubricating composites prepared by powder metallurgy were investigated.The results show that the micro-hardness of composites decreases obviously with the increase of content of MoS_2.While the friction coefficient and wear rate of the composites don＇t change evidently with increasing the content of MoS_2 from 10%to 15%（mass fraction）.The micro-hardness of composites reduces gradually with the rise of graphite amount,the friction coefficient of composites increases slightly at 400℃and 800℃.When the content of graphite is 10%,the friction coefficient of composite is lowest at room temperature.Addition of 5%MoS_2 and 10%graphite,the friction coefficient of composites keeps 0.48-0.65 meaning the synergic lubricating effect between graphite and MoS_2,and the wear rate is an order of magnitude higher than that of composites containing MoS_2 alone or graphite alone.