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.