Effects of sliding friction angle and load on the friction and wear properties of silicon nitride ceramics under dry friction

Purpose This study aims to improve the wear resistance of silicon nitride (Si3N4) ceramics, the effects of sliding friction angle and load on the friction and wear properties and wear mechanism of Si3N4 ball/block pair were investigated. Design/methodology/approach Under dry friction conditions, the surface profiles of Si3N4 ceramic blocks at different test angles were observed by the Taylor roughness meter. Then, the reciprocating sliding friction test method was used to explore the friction and wear properties of Si3N4 ball/block pairs under different sliding friction angles and loads. Findings The surface profile curves of Si3N4 ceramic block under different contour measurement angles are quite different. The density and fluctuation of peaks and troughs in the surface profile will affect the number of friction contact points and the load of each contact point, which will significantly affect the friction and wear properties of the Si3N4 ball/block pair. The friction coefficient and wear rate of the Si3N4 ball/block pair under different test loads decrease with the increase of sliding friction angle. At the same time, with the increase of load and sliding friction angle, the Si3N4 ball/block pair is more conducive to the occurrence of adhesive wear. The formation of a smooth adhesive layer by adhesive wear is the key to reducing the friction coefficient and wear rate of the Si3N4 ball/block pair. Originality/value The research results are of great significance for revealing the tribological properties of Si3N4 ceramics and improving their wear resistance and performance.