Development Of Permanent Magnetic Poles Based On Freeform Surface Finishing And Experimental Studies On Their Working Performance

Finishing is the last procedure of part manufacturing, and its surface finishing quality affects directly the using performance and using time of the products. Though machine industry has automated highly, complex curved surface finishing is done by hand work of well-skilled workers, which is not only bigger in laboring intensity, but also lower product quality and finishing efficiency. Magnetic abrasive finishing shows huge superiorities on curved surface finishing because of its outstanding machining advantages for example, well flexibility, self-adaptability, self-sharpness and so on. In order to improve finishing quality and finishing efficiency of magnetic abrasive finishing, enhance practicability of magnetic abrasive finishing, solve automatization problem of complex curved surface finishing, based on reading plentiful literatures, by theory analysis and great design experiment, this paper made a systematic study on the techniques of magnetic abrasive finishing and automatic finishing of curved surface.Based on knowing the basic knowledge of permanent magnetic materials, the paper applies strong permanentmagnetic materialNd-Fe-B to magnetic abrasive finishing,designs five permanent magnetic poles. They are respectively inlaied magnetic pole, open-circuit spheral magnetic pole, open-circuit planar magnetic pole, closed-circuit spheral magnetic, closed-circuit planar magnetic pole, which are applied to finish curved surfaces and planes of different materials. Acting as magnetic grinders, these magnetic poles not only solve problems that electromagnetic magnetic poles exist, but also have many advantages, for example: structure simpleness, volume smallness, weight lightness, magnetic energy highness that are reserved, no electrical source, furthermore, exchanged magnetic poles on the basis of need and so on.This paper made a lot of experiments on every magnetic pole in order to test their machining performance, especially on inlaied magnetic pole and open-circuit spheral magnetic pole that were applied to finish freeform curved surfaces. By making experiments, one the one hand, author knew their finishing performance and existed disadvantages, on the other hand, author found some factors that affected curved surface finishing, and analyzed on them thought theory analysis. All were provided to the application of magnetic abrasive finishing technology onfreeform curved surface finishing. At the same time, experiment results show: when finishing magneto-conductive materials, open-circuit spheral magnetic pole' s finishing effect is the finest and adaptability is the strongest; because of "magnetic field weaker zone" and "magnetic field weakest zone" , inlaied magnetic pole' s finishing effect is not fine, and needs to improve further; magnetic poles that are applied to finish planes can basically finish workpiece surfaces effectively.On this paper, all experiments were accomplished on the numerical control machine. All magnetic poles can connect easily with numerical control machine' s principal axis, magnetic poles can carry out workpiece surfaces finishing if only they move according to numerical programmes that were programmed in advance, which achieves automation of magnetic abrasive finishing. All these will lay a foundation on full automation of freeform curved surfaces magnetic abrasive finishing.