Tribological properties of laser-textured and ta-C coated surfaces with burnished WS2 at elevated temperatures

The possibility of enhancing the tribological properties of ta-C at elevated temperature (250 °C) by laser surface texturing and burnished WS2 addition were investigated. Laser texturing was applied prior to ta-C coating process. Samples were tribologically tested at room temperature and elevated (250 °C) temperature using pin-on-disc. WS2 addition increased remarkably the wear life of ta-C at 250 °C and low COF values (0.01–0.02) were achieved. Laser surface texturing (LST) increased the wear life of WS2/ta-C surfaces by more than two times compared to non-textured surface. The LST dimples functioned as solid lubricant reservoirs and improved the wear life of the initial WS2 layer. This was noticed to be related to wear mechanism with raised position dimples and partly oxidized WS2.