The tribological properties of Pb-free FeS/Cu–Bi (FCB) self-lubricating composites were optimised with the Taguchi method. The effects of lubricant content and ball milling time on the anti-friction and wear resistance of FCB composites were investigated. Then the evolution of the friction interface was observed through interrupted microscopy measurement to reveal its synergistic lubrication mechanism. The results showed that the primary and secondary factors that affected the anti-friction and wear resistance of the FCB composites were FeS content, Bi content and ball milling time. The synergistic lubrication mechanism of FCB composites was that FeS could prevent the crack from extending with the continuous Bi mesh and could prevent the matrix with Bi debris from peeling off, which was conducive to the formation of a lubricant-rich tribofilm at the friction interface to improve the tribological properties of the composites.

中文翻译：

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无铅 FeS/Cu-Bi 复合材料的摩擦学性能优化和协同润滑演化

采用田口法优化了无铅 FeS/Cu-Bi (FCB) 自润滑复合材料的摩擦学性能。研究了润滑剂含量和球磨时间对FCB复合材料减摩耐磨性能的影响。然后通过断续显微镜测量观察摩擦界面的演变，以揭示其协同润滑机制。结果表明，影响FCB复合材料减摩和耐磨性能的主次因素为FeS含量、Bi含量和球磨时间。FCB复合材料的协同润滑机理是FeS可以防止裂纹与连续的Bi网格一起扩展，并且可以防止Bi碎屑的基体剥落，