Effects of environmental temperature and sliding speed on the tribological behaviour of a Ti-based metallic glass

This paper provides an in-depth investigation into the effects of environmental temperature and sliding speed on the tribological behaviour of a bulk metallic glass (BMG), Ti40Zr25Ni3Cu12Be20. The sliding was between the BMG and EN26 steel. The results showed that the wear resistance of the BMG increases with environmental temperature when it is below the material's glass transition temperature (Tg); and that the steady friction coefficient does not vary notably. The stress on the contacting asperities influences the wear rate. Wear debris also play an important role at elevated temperatures, which could even change the wear mechanism from 2-body abrasion to 3-body abrasion under certain environmental temperature. The BMG remains amorphous, even at an environmental temperature close to its Tg, indicating that frictional heating controls the microstructure transformation during contact sliding. Under a high environment temperature, a dissimilar material layer could emerge at the sliding interface, leading to a significant reduction in wear rate.