LAUSR

Abstract Gallium-based liquid metal is potential lubricant on account of its high load capacity and thermal stability. However, the lubrication performance of gallium-based liquid metal (LM) is limited by its metallic characteristics. In this work, hexagonal boron nitride (h-BN) nanosheet with good lubricity is utilized as additive to enhance lubrication behaviors of LM. The bonding between LM and h-BN particles is reversible. In alkaline solution, LM is able to be separated from h-BN particles and agglomerate to bulk liquid metal. Moreover, our frictional tests demonstrate that when using h-BN as additive in LM, it holds enhanced tribological performance including reduction of the friction coefficient and wear rate in contrast to the pure LM. Moreover, the study of the lubrication mechanisms suggests that the adhesion of LM and deposition of h-BN are the critical factors for improving lubricity. This work proposed a facile method to improve the tribological behaviours of LM and promoted the understanding of the lubricating principles of LM and h-BN.