青铜—石墨复合材料在干摩擦和水润滑下的摩擦磨损性能及磨损机理研究

对比考察了青铜 -石墨复合材料在水润滑和干摩擦两种状态下的摩擦磨损性能及磨损机理 .结果表明 :水润滑下青铜 -石墨复合材料的磨损率明显比干摩擦下的小 ,其最小磨损率为 1.0 1× 10 -6mm3 /N·m ,而摩擦系数比干摩擦下的大 ,复合材料在干摩擦下的磨损机理主要为粘着磨损、剥层磨损和犁削 ,磨损较严重 ;而在水润滑下 ,复合材料的磨损机理主要为磨粒磨损和疲劳磨损 ,磨损较小 .这是因为水有利于降低摩擦副接触表面的温度 ,有效地抑制了基体青铜的转移 ;同时水促进了不锈钢偶件的氧化 ,形成薄而致密氧化膜 ,从而降低了磨损

A Comparative Investigation of the Tribological Behavior and Wear Mechanism of Bronze-graphite Composite under Dry- and Water-lubricated Sliding against Steel

The friction and wear behavior of bronze-graphite composite under dry- and water-lubricated sliding against a stainless steel was comparatively investigated with an MM-200 friction and wear tester. The wear mechanisms of the composites were examined as well based on scanning electron microscopic and X-ray photoelectron spectrometric analyses of the worn surfaces of the composite and counterpart. As the results, the composites registers lower wear rate and higher friction coefficient under water lubrication at a relatively smaller sliding speed. Little difference in the friction coefficient and wear rate is observed for the composite under both dry- and water-lubricated conditions as it slides against the steel at a relatively higher sliding speed. The composite is characterized by adhesion wear and scuffing under dry sliding, while it is characterized by abrasion and fatigue under water-lubricated sliding. The cooling effect of water helps to abate the surface temperature rise and restrain the adhesion and transfer. This contributed to decrease the wear rate. Though the oxidation of the counterpart steel was enhanced by water as the lubricant medium, the resultant generation of a compact oxide film contributes to restrain the adhesion and transfer and hence reduce the wear rate of the frictional pair.