Tribological behavior of ZrO2/WS2 coating surfaces with biomimetic shark-skin structure

This study demonstrated the dry friction and wear behavior of sol-gel ZrO2/WS2 coatings with biomimetic sharkskin textured surfaces. The effect of added WS2 on the microstructure and mechanical properties of ZrO2 coatings was examined and the dry sliding wear and friction behaviors against commercial AISI1045 steel balls were investigated. After adding WS2, the micro hardness of ZrO2 coating decreased by similar to 39% (from 23.7 GPa to 14.5 GPa), and the average steady state friction coefficient was decreased from similar to 0.43 to similar to 0.2. When the ZrO2/WS2 coating surface was textured biomimetic shark skin, nearly 66% decrease of the average steady state friction coefficient and 82% decrease of ball wear rate were obtained as compared with the pure ZrO2 coatings. The possible frictional mechanism of the biomimetic shark-skin structures was discussed.