High-Temperature Tribological Behaviors of In Situ–Formed TiAl-TiB₂ Composites in Low-Pressure Oxygen

Abstract

The tribological behaviors of in situ–formed TiAl-TiB₂ composites were investigated from room temperature to 800 °C in low-pressure oxygen and related to their hardness and partial tribo-oxidation behaviors on the frictional surface. The wear resistance of TiAl-TiB₂ composites in low-pressure oxygen is significantly enhanced when the TiB₂ content increases from 0 to 20 vol% but decreases with a further increase in TiB₂ content to 30 and 40 vol%. The wear rates of the TiAl-TiB₂ composites are low below 200 °C and increase within 400–600 °C due to their decreased hardness and reach minimum values at 800 °C. The hardness of the composites and the degree of surface tribo-oxidation codetermine the wear resistance.

Keywords:

• TiAl-TiB₂ composite
• high temperature
• sliding wear
• low-pressure oxygen

Additional information

Funding

This work was funded by the National Key Research and Development Project (2018YFB0703803), the National Natural Science Foundation of China (51975557), and the Outstanding Youth Fund of Gansu Province (20JR5RA571).