Influence of secondary electro-conductive phases on the friction and wear response of ZrO2-based composites

ZrO2-40vol.%WC, ZrO2-40vol.%TiCN and ZrO2-40vol.%TiN composite flats were surface finished by wire-EDM, grinding and polishing. Their reciprocative dry sliding friction and wear behavior against WC-6wt.%Co cemented carbide pins was compared using a Plint TE77 tribometer. The worn surfaces and wear debris of the ZrO2-based composite grades were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and surface topography. Correlations between wear volume, wear rate and coefficient of friction on the one hand and material properties on the other hand were determined. Based on the experimental results, a strong dependence of tribological characteristics on the secondary electro-conductive phase as well as on surface finishing conditions was evinced