Abstract:In order to study the effect of graphene on the tribological and rheology properties of lithium based greases,lithium-based greases modified with different mass fraction of few-layer graphene were prepared by mechanical stirring,ultrasonic dispersion and three-roll grinding,and their tribological and rheological properties were investigated using an MR-10 four-ball tester and a DHR-2 rotational rheometer,respectively.The results show that the addition of few-layer graphene can effectively improve the anti-wear and friction reducing properties of lithium-based greases,and the best effect is achieved when the mass fraction of few-layer graphene is 0.1%.The addition of few-layer graphene significantly increases the strain value corresponding to the flow point of the lubricating grease,the energy required to break the lubricating grease soap fibers,and the time needed for soap fiber structure recovery after damage.By regression analysis of the experimental data,the flow equations of lithium-based grease with different mass fraction of few-layer graphene were established based on the Herschel-Bulkley model.