Abstract:Due to the particle self-wear and friction between particles and the working wall of magnetorheological (MR) brake, the braking effect of MR brake will be affected. Therefore, it is very important to analyze the tribological performance of MR fluid. In this study, four kinds of MR fluid (MRF) were prepared with graphite and grease of silicone fluid as extra additives. First, the working condition of MRF in elevator transmission device was simulated by four-ball test machine. The friction coefficient changing of MRF was recorded, and the size of wear scar was observed and measured by image microscope. Then, by measuring the changes of the rheological properties of MRF before and after the friction experiment with rheometer, the influence of friction and wear on performance of the MRF in the device was analyzed. The experimental results show that the additive can reduce the friction of MRF to a certain extent, and the rheological properties increase after friction. The prepared MRF number 3 has low zero-field viscosity, high yield shear stress, and good stability, suitable for the MRF of traction elevator brake.