Tribological characterization of an alumina-based composite in dry sliding contact against laser-heated and unheated Inconel 718

Alumina-based ceramic tools have been successfully applied in high-speed turning of superalloys. In this study, the tribological characteristics of a novel Al₂O₃-SiC_w-TiC_n ceramic composite were investigated in unlubricated sliding contact against laser-heated (600 °C) and unheated Inconel 718 between 2.5 m/s and 10 m/s. The tribological behavior of the Al₂O₃-SiC_w-TiC_n ceramic was compared to a commercial Al₂O₃-SiC_w ceramic. The results indicated similar coefficients of friction (COF) in laser-heated and unheated tests. Below 7.5 m/s, the wear mechanisms in laser-heated tests were brittle fracture, plastic flow and adhesive wear and predominantly brittle fracture in unheated tests. A tribochemical layer mainly containing chromium and oxygen has formed on the contact surface at 10 m/s resulting in lowering the COF and reducing wear.