Squeeze-Strengthening Effect of Silicone Oil-Based Magnetorheological Fluid with Nanometer Fe3O4 Addition in High-Torque Magnetorheological Brakes

With the aim of studying the squeeze-strengthening effect of silicone oil-based magnetorheological fluid (MRF) with nanometer Fe3O4 addition in high-torque magnetorheological (MR) brakes, the theoretical analysis of the disc brake is presented and a high-torque squeezing MRF brake with a water cooling method for heat dissipation is designed. Furthermore, an experimental system to evaluate the squeeze-strengthening performance of the MRF in the high-torque MR brake is established and relevant experiments are performed. The experimental results indicate that the high-torque squeezing MRF brake we designed possesses excellent magnetic properties and stability. The shear yield stress of the silicone oil-based MRF with nanometer Fe3O4 addition exhibits an almost linear increase with the increase in the axial or radial squeezing stress, and the braking torque increases 1300 N.m and 410 N.m when the corresponding axial and radial squeezing stress are 1.5 MPa and 2 MPa, respectively.