一、引言电加工能够弥补早已普遍应用的机械切削和磨削等加工的不足,故从它作为一项新工艺出现以来,有了飞跃的发展。目前已经超出了特种加工的范畴,成为一种独立的加工方法,在工业上作出了很大贡献,获得了高度的评价。在电加工作为特种加工方法而出现的初期,因为它能够加工用其它方法不能加工或加工极为困难的工件,所以,尽管在加工性能和加工缺陷等方面不如以往的加工方法,然而 I. INTRODUCTION Electro-machining can make up for the shortcomings of mechanical cutting and grinding, which have been widely used in the past. Therefore, since it appeared as a new process, it has made leaps and bounds. Now beyond the scope of special processing, as an independent processing methods, made a significant contribution to the industry, received a high rating. In the early stage of electric machining as a special processing method, since it was able to process an extremely difficult workpiece which could not be processed or processed by other methods, it was inferior to conventional processing methods in terms of processing performance and processing defects,