The invention relates to a dynamic
magnetic field self-
sharpening finishing device for a flexible
magnetorheological finishing pad and a finishing method for the dynamic
magnetic field self-
sharpening finishing device. The dynamic
magnetic field self-
sharpening finishing device comprises a finishing disk revolution mechanism and a multi-magnetic-pole synchronous rotation driving mechanism, wherein the finishing disk revolution mechanism comprises a driving shaft motor, a
drive shaft, an adapting disk, an eccentric shaft fixing disk, a cup-like finishing disk and a driving shaft transmission mechanism; the multi-magnetic-pole synchronous rotation driving mechanism comprises an eccentric spindle, synchronous rotation driving plates, flexible eccentric rotating shafts, eccentric sleeves,
magnetic poles, the eccentric shaft fixing disk, a spindle motor and the like. According to the finishing device and the finishing method disclosed by the invention, the conditions that a circulating device is adopted for updating
magnetorheological fluid and the
magnetorheological fluid is changed in the
processing process are avoided, so that the space is saved, and the whole process from rough finishing to fine finishing can be realized by one-
time processing; obtained workpieces are good in surface consistency, high in
processing efficiency, free from of surface and subsurface damage and low in cost, so the finishing device and the finishing method are suitable for high-efficiency ultra-smooth uniform finishing
processing of planes of large-
diameter optical elements; meanwhile, the finishing device and the finishing method disclosed by the invention are also suitable for experimental researches such as a material removing mechanism and subsurface
damage detection of optical planar materials.