Torsional Fretting Wear Properties of Thermal Oxidation-Treated Ti3SiC2 Coatings

Abstract

In this study, efforts were made to oxidize the Ti3SiC2 coating surface to improve its wear resistance by producing oxide layers and healing microcracks that initiated from the thermal sprayed process. Tribological behaviors of the thermal oxidation-treated Ti3SiC2 coatings subjected to various temperatures (200, 300, and 400 °C) and durations (1, 3, and 5 h) were investigated comparatively by fretting wear. The results showed that the thickness of the oxide layer and the average content of element O on the surface were gradually increased with increasing temperature. Lower friction coefficients were observed in coatings at 200–400 °C for 1 h. Better performance of crack-healing features was demonstrated at 400 °C, whereas fresh microcracks were formed under the fretting condition due to the fragility of oxides at the same time. The tribological behavior of thermal oxidation-treated Ti3SiC2 coatings was mainly controlled by delamination and abrasive wear. The volume losses induced by wear scars decreased with the increase in oxidation time under the oxidation treatment at 200 °C and increased with increasing oxidation time under the oxidation temperatures of 300 and 400 °C.