In order to improve the plane polishing efficiency of the cluster magnetorheological, some polishing disks with different microstructures were proposed to increase the hydrodynamic pressure of the plane polishing. Polishing experiments and polishing force characteristic experiments were carried out on the plane polishing disk and polishing disks with different microstructures such as holes, V-shaped grooves, U-shaped grooves and rectangular grooves on the surface. The influences of machining gap and workpiece rotation speed on the polishing effects were studied. The results show that the microstructures on the surface of the polishing disk have a great influence on the material removal rates of the workpiece. The material removal rates of the various disks are V-shaped disk>U-shaped disk>plane disk>hole-shaped disk>rectangular disk. The material removal rate of V-shaped disk is 25% greater than that of the plane disk. However, the disk structures have little effects on the surface roughnesses and all the polishing disks with different microstructures can obtain nano-scale (less than
Ra 8 nm) surface. In this test, the better polishing effect can be obtained under the condition of the polishing gap 0.9-1.0 mm and the workpiece speed 550 r/min.