Ni-Al基自润滑复合材料的制备及其摩擦学性能

摘要

Ni-Al based self-lubricating composites were prepared by powder metallurgy method. The influence of sintering temperature on mechanical and tribological properties of composites was investigated and the tribological properties of composites in different testing conditions were discussed as well. The results show that the higher the sintering temperature, the higher the compactness and micro-hardness of composites, and the tribological properties of composites were more stable. The effects of applied load and reciprocating frequency on tribological properties of composites are as following: the greater the load, the lower the friction coefficient; the higher the frequency, the higher the friction coefficient of composites. Furthermore, the microhardness of Ni-Al-based self-lubricating composites with 5 wt. ％ flake graphite is obviously decreased comparing with that of the composite without flake graphite, and the friction coefficients of composites with graphite were likewise lower than that of the composite without graphite at both ambient temperature and 600℃.%本文采用粉末冶金的方法制备了Ni-Al基自润滑复合材料并研究了烧结温度对复合材料的机械及摩擦性能的影响,同时讨论了复合材料在不同试验条件下的摩擦磨损性能.结果表明,烧结温度越高,复合材料的致密性和显微硬度越高,摩擦性能也越稳定.在摩擦磨损试验过程中,试验载荷和频率对复合材料的摩擦性能也有一定影响,在其它参数不变的情况下,载荷越大,自润滑材料的摩擦系数越小;频率越大,材料的摩擦系数越大.加入5wt.%鳞片状石墨后,Ni-Al复合材料的硬度明显降低,摩擦系数在室温和600℃有不同程度的降低.