青铜-石墨热喷涂层在干摩擦和水润滑条件下的摩擦磨损性能

在MM-200摩擦磨损试验机上研究了青铜-石墨热喷涂层在干摩擦和水润滑条件下的摩擦磨损性能,采用扫描电镜(SEM)对磨损表面形貌进行了观测和采用X射线能谱分析(XPS)分析了涂层成分。结果表明,在水润滑条件下涂层摩擦因数和磨损率均低于干摩擦条件下;在水润滑条件下磨损机制为轻微磨粒磨损和犁削磨损,在干摩擦下主要是较为严重的粘着磨损和犁削。这是由于水润滑降低了摩擦副界面温度,提高了石墨润滑膜的韧性,改善了润滑效果,从而阻止了粘着磨损的发生,水还促进了钢偶件表面致密氧化膜的形成,从而减轻磨损。因此水润滑对涂层磨损性能有较大影响。

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

The tribological property of bronze-graphite thermal spraying coating under dry and water-lubricated sliding against stainless steel was comparatively studied with the MM-200 friction and wear tester.The wear mechanisms of the coating were examined based on scanning electron microscopic and X-ray photo electron spectrometric analyses of the worn surfaces of the composite and counterpart.As a results,the friction coefficient and wear rate under water-lubricated is lower than that under dry sliding.The wear mechanism under water-lubricated is slight abrasion and plough wear,and it is adhesion and plough wear under dry sliding.The surface temperature of couple-material is decreased and the toughness of graphite lubricating film is improved under water-lubrication,so the adhesion wear is restrained.The generation of compact oxide film on the surface of counterpart steel is promoted by water,hence the wear rate is reduced.So water-lubricated has great effect on wear property of the coating.