Effect of textures formed by mechanical treatment and laser radiation on tribological properties of silicon carbide ceramic surfaces

The effect of platykurtic and leptokurtic textures formed on silicon carbide ceramic (SiC) surfaces on tribological properties under dry sliding conditions was experimentally studied. Platykurtic textures were formed using grinding and polishing methods. Leptokurtic textures were obtained by treating surfaces with nanosecond laser radiation. Texture analysis was performed using three-dimensional roughness parameters Sa, Ssk, Sku and Spd. It was found that the friction coefficient of platykurtic texture is influenced to a greater extent by the shape of asperities (Sku) and the density of asperities (Spd) than by the predominance of depressions over asperities (Ssk). For the leptokurtic texture formed by laser radiation, the shape of asperities (Sku) has a much smaller effect on the friction coefficient than the asymmetry (Ssk) and the density of asperities (Spd). Therefore, laser treatment of ceramic surfaces leads to the formation of a leptokurtic texture characterized by a high initial friction coefficient (more than 0.5) under dry sliding conditions. In practice, such a higher friction coefficient during the running-in period is necessary to prevent wear of components such as dovetail, groove, and screw connections.