Investigation of high temperature tribological performance of TiZrV0.5Nb0.5 refractory high-entropy alloy optimized by Si microalloying

Effect of Si addition on the high temperature tribological properties of TiZrV0.5Nb0.5 refractory high entropy alloy was systematically studied. The results demonstrate that Si-microalloying affects the tribological properties by modulating the evolution of tribo-layer. Si-microalloying produces local tribo-layer with strong wear resistance by increasing the sintering rate of wear debris below 600 degrees C, ultimately significantly reducing the coefficient of friction and wear rate. At 600 degrees C, Si-microalloying deteriorates the wear resistance due to the stress concentration at hard particles leading to accelerated fracture of the tribo-layer which hinders the formation of continuous protective tribo-layer. The enhanced tribological properties at 800 degrees C are attributed to the synergistic effect of suppressed oxide volatilization and rapid oxidation behavior ensuring continuous dense tribo-layer formation.

Automated summary

The effect of Si addition on the high temperature tribological properties of TiZrV0.5Nb0.5 refractory high entropy alloy was systematically studied. The results show that Si-microalloying can modulate the evolution of tribo-layer, thus affecting the tribological properties. Si-microalloying increases the sintering rate of wear debris at low temperatures, resulting in a local tribo-layer with strong wear resistance. However, at high temperatures, Si-microalloying leads to stress concentration and accelerated fracture of the tribo-layer, reducing the wear resistance.