High efficiency ELID grinding of garnet ferrite

Hard and brittle materials such as ferrite, optical glass and ceramics have been used in many fields and still gain increasing attention. They are difficult to machine and it is hard to obtain good surface quality. Some workpieces of large batch production have large machining allowances and the machining efficiency is low with the usual grinding method. Thus it is of great importance to research the high efficiency grinding technology of hard and brittle materials. In this paper a cast iron bond diamond wheel and ELID (electrolytic in-process dressing) grinding technology are used on a surface grinder to research the high efficiency grinding technique. ELID grinding has been used previously in precision grinding with a fine abrasive wheel. In this study, the feasibility of ELID grinding for high efficiency deep-cut grinding has been researched. Garnet ferrite (YAG) has been machined both by the new method and by using a resin bond diamond wheel. The grinding force of the cast iron bond diamond wheel with ELID technology is apparently smaller than that of the other method. Under the same conditions, it is about 2/5-3/5 of the force using the resin bond diamond wheel. The result indicates that the grinding efficiency of garnet ferrite can be highly improved and good surface quality ensured by applying ELID grinding technology and adopting a large grinding depth.