Lubrication properties of gallium-based liquid metals by doping bismuth

Abstract

Ga-based liquid metal (GLM) is a promising high temperature lubricant but its lubricating properties still need to be further improved. In this work, the lubrication properties of bismuth doped Ga-base liquid metal in a vacuum environment were studied in a wide temperature range from room temperature (RT) to 600 °C, where the self-mated Inconel 625 alloy sliding-pairs were selected. The results indicate that the addition of a small amount of bismuth (0.5 wt%) in GLM can enhance its lubricating performance by suppressing the oxidation of gallium within the temperature range of 200 °C to 600 °C, thereby decreasing the wear of Inconel 625 alloy.