Fretting wear properties of plasma-sprayed Ti3SiC2 coatings with oxidative crack-healing feature

The present research describes a study to explore the possibility to improve the wear resistance by healing microcracks that initiated under fretting wear. To this aim Ti3SiC2 coatings prepared at different plasma powers (33 and 34 kW) were investigated comparatively under fretting. The results showed that the amount of Ti3SiC2 phases was higher at the lower plasma power, leading to a major difference on fretting wear properties. Coatings with a higher content of Ti3SiC2 phases exhibited a remarkable decrease in the friction coefficient and an enhancement in the wear resistance. The enhanced wear resistance was mainly attributed to the healed cracks by selective oxidation of Ti3SiC2. The reduced friction coefficient was strongly related to the formation of tribo-induced oxides.