Tribological properties of dimpled silicon nitride under oil lubrication

It is known that under lubricated conditions, dimpled surfaces can show improved tribological properties under planar/planar contact. This study investigates the effect of dimpling on the tribological properties of a silicon nitride ceramic against hardened bearing steel under oil lubricated, planar to curved surface contact conditions. Block-on-ring friction tests under oil lubrication were carried out over a range of sliding velocities, with a silicon nitride ceramic whose surface was dimpled by abrasive jet machining (AJM). The dimpled surface showed better tribological properties in terms of reduced friction coefficient compared with a lapped surface.