Preparation and Tribological Properties of Ni-Al-based Self-lubricating Composites

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 micro-hardness 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℃.