In order to solve the problems such as the easy deformation and poor recovery of magnetic brush in conventional magnetic abrasive finishing method, a new magnetic abrasive finishing method has been proposed in this study. By using alternating current, the coil can produce alternating field in magnetic circuit. Since alternating magnetic field, the magnetic particles can form magnetic brush periodically that can keep it having a good shape during finishing process. From theoretical formulas, the relationship of the frequency between alternating current and alternating magnetic force is investigated. The results are the same with the measure results. At last, a multi-stage finishing experiment is performed with the alternating magnetic field abrasive finishing process. There are two steps in this finishing, rough finishing and ultra-precision finishing. The results show that surface roughness can be improved from 230 nm Ra to 19 nm Ra in 60 minutes.
