High-temperature tribological behavior of a Ni-based bulk metallic glass

Ni-based bulk metallic glasses (BMGs) are emerging as promising candidates for high-temperature tribological applications due to their superior mechanical strength and remarkable thermal stability. This study aims to examine the high-temperature tribological behavior of a representative Ni-based BMG, Ni 59.2 Nb 38.8 P 2 , over an extensive temperature range from room temperature (RT) to 550 °C. The results obtained reveal that the alloy exhibits exceptional wear resistance in the RT–300 °C range, with wear rates gradually increasing from 3.26 ± 0.4 × 10 -6 mm 3 N -1 m -1 to 7.30 ± 0.5 × 10 -6 mm 3 N -1 m -1 . However, at elevated temperatures, wear performance declines significantly, reaching 28.40 ± 1.2 × 10 -6 mm 3 N -1 m -1 at 450 °C and escalating to 99.40 ± 1.2 × 10 -6 mm 3 N -1 m -1 at 550 °C. This trend indicates a transition in the dominant wear mechanisms—from mild abrasive and oxidative wear to severe oxidative, adhesive, and abrasive interactions. The conducted structural analysis displays increased oxidation at higher temperatures, accompanied by distinct crystallization at 550 °C under combined thermal and mechanical stresses. These findings crucially shed light on the wear mechanisms and structural evolution of the Ni 59.2 Nb 38.8 P 2 BMG under high-temperature conditions, offering valuable insights for its application in thermally and mechanically demanding tribological environments.