Development of High-Efficiency Finishing Machine by Magnetic Float Polishing

磁流体是亚域铁磁粒子在各种载液中的胶体分散体。当磁流体被置于磁场梯度中时，它被吸引到磁场较高的一侧。如果将非磁性物质浸入磁性流体中，则将其相对较低的磁场侧排出。磁浮抛光是磁浮力的一种应用。在此过程中，旋转工件被压在浮在磁性流体上的非磁性磨料上。本课题进行了高效磁浮抛光机的研制。从一系列的调查中，澄清了以下几点。1)为了施加磁场，必须使用悬浮在磁性流体中的磁性磨料或非磁性磨料。2)磁浮抛光的抛光能力受磁场梯度、复合材料粘度或磨料与磁流体的亲和力的影响。3)精加工机上宜采用永磁体，因为永磁体的磁场强度比电磁铁强。4)在磁流体上使用复合磨料作为研磨磨料的工艺比磁浮抛光具有更好的抛光能力。

Magnetic Fluids are colloidal dispersions of subdomain ferromagnetic particles in various kinds of carrier liquids. When magnetic fluid is placed in magnetic field gradient, it is attracted towards the higher magnetic field side. if a nonmagnetic substance is immersed in magnetic fluid, it is discharged relatively to lower field side. Magnetic Float Polishing makes an application of the magnetic buoyant levitational force. In this process the revolving workpiece is pressed to the nonmagnetic abrasives floating on the magnetic fluid.In this project the development of high-efficiency finishing machine by Magnetic Float Polishing was performed. From the series of investigations, the following points have been clarified.1) Either magnetic abrasives or nonmagnetic abrasives suspending in magnetic fluid must be used in order to apply magnetic field.2) Finishing abilities in Magnetic Float Polishing were affected by the magnetic field gradient, the viscosity of the compound or the affinity between abrasives and magnetic fluid.3) Permanent magnets are desirable to use in the finishing machine, because permanent magnets have stronger magnetic field strength than electric magnets.4) The process which the compound on the magnetic fluid was used as a lapping abrasives has better finishing abilities than Magnetic Float Polishing.