The role of oxidation and counterface in the high temperature tribological properties of TiAl intermetallics

Highlights: • Oxidation is detrimental for wear resistance below 600 °C but favorable at 800 °C. • The mechanism simulating the role of oxidation on the wear process is proposed. • Counterface has a strong influence on the tribological properties of TiAl alloy. • The effect of counterface is strongly dependent on the system environment. - Abstract: Clarification of how oxidation and counterface materials influence the high temperature tribological properties of TiAl alloy is the main object of this research. As evident from the comparison tests in air and argon, surface oxidation is detrimental to the tribological properties of the alloy at low temperature, but favorable above 600 °C. Counterface (Si₃N₄, SiC and Al₂O₃) is an important factor that largely affects the tribological properties of TiAl alloys, and this effect is strongly dependent on the system environment. In general, TiAl alloy shows superior tribological properties when Al₂O₃ is mating surface, excluding at 800 °C in argon.