Tribological properties of TiAl matrix self-lubricating composites incorporated with tungsten disulfide and zinc oxide

Abstract

To better understand the temperature-adjusted action of tungsten disulfide (WS₂) and zinc oxide (ZnO) in self-lubricating composites, dry sliding tribological properties of TiAl matrix self-lubricating composites (TMSC) containing WS₂, ZnO and WS₂–ZnO against Si₃N₄ counterface are comparatively investigated from 25 to 800 °C. Tribological results suggest that TMSC containing WS₂–ZnO exhibit the lowest friction coefficients and wear rates than TMSC containing only WS₂ or ZnO over the wide temperature range, confirming the self-adjusted action of WS₂–ZnO as the temperature changes. Specifically, WS₂ is beneficial to the improvements of tribological properties within 200 °C, WS₂ and ZnWO₄ for 400 °C, ZnWO₄ and ZnO for 600 °C and ZnO for 800 °C.