锡青铜梯度自润滑复合材料的摩擦学性能

Tribological Behavior of Tin-Bronze Gradient Self-lubricating Composites

利用粉末冶金工艺设计和制备了新型润滑材料——锡青铜梯度自润滑复合材料;在MM-200型摩擦磨损试验机上考察了其摩擦学性能,利用扫描电子显微镜观察分析了磨损表面形貌,进而探讨了其摩擦磨损机理.结果表明:锡青铜梯度自润滑复合材料摩擦学性能优异,且偶件损伤轻微;所研制的锡青铜梯度自润滑复合材料的摩擦学性能优于目前国内常用的金属润滑材料555铅青铜、6501锡青铜以及进口多层金属润滑材料;锡青铜梯度自润滑复合材料的优异减摩抗磨性能取决于其特殊的梯度结构.

Tin-bronze gradient self-lubricating composites were designed and prepared by powder metallurgy process. The tribological behaviors of the resulting gradient self-lubricating composites sliding against SAE52100 steel in a block-on-ring configuration were investigated on an MM-200 friction and wear tester. The surface morphologies of the wear tracks were observed with a scanning electron microscope. The wear mechanisms of the gradient self-lubricating composites were discussed as well. It was found that the self-lubricating composites showed better friction-reducing and antiwear properties than conventional metal-based lubricating materials at home and multilayer metal-based lubricating materials abroad. They led to negligible damage to the counterpart as well, which was attributed to the formation of a transfer film of the gradient self-lubricating composites on the counterpart surface. The excellent tribological behaviors of the gradient self-lubricating composites were attributed to their special gradient structures, which was characterized by the gradually decreased hardness from the surface to the inner layer and the gradient decreased shearing strength from the inner layer to the surface.