中文摘要：

研究N型锗晶体放电加工中体现的单向导通性、表面电化学现象以揭示其特殊放电加工特征。试验发现N型锗晶体放电加工无法持续,其主要原因是进电接触面产生电解并生成不导电、不溶解的氧化物且阻塞在进电接触面缝隙内。为避免在进电接触区产生电解,设计表面涂覆碳浆进电法;为避免进电接触区产生不导电、不溶解氧化物,设计了电极随动进电法,并对这两种进电方式进行试验比较。结果表明,前者可以在一定时间内改善N型锗晶体进电,但仍不能达到长期稳定进电的效果,而后者则可以保障极间获得稳定和较小的极间电阻及持续稳定的进电效果。通过放电切割试验初步揭示半导体材料放电加工体现的放电期间电流爬坡上升、放电蚀除以热应力蚀除为主、极性效应需要进行拓展性解释等特殊的半导体材料放电加工特性。

英文摘要：

Unilateral conductibility and superficial electrochemical properties represented in n-type germanium crystal electrical discharge machining（EDM） are researched in a bid to reveal the special characteristics of this material during EDM process.It is discovered that the n-type germanium crystal EDM cannot be sustained,and this is due to electrolysis emergence on the contact surface of providing power and consequently forming non-conducting insoluble oxide blocking the gap between the contact surfaces.In order to prevent electrolysis from occurring,a method to apply carbon paste coating on the contact surface is designed.On the other hand,for the purpose of removing non-conducting insoluble oxide on the contact surface,the method of electrode servo power providing is designed.Then the two power providing methods are compared.Results show that the former is able to improve the power providing condition of n-type germanium crystal for a certain period of time but can＇t achieve the long-term stability,while the latter can assure the steady lower inter-electrode resistance and the persistent effect of power providing.Through the wire-cut EDM（WEDM） experiment,special phenomena of semiconductor material in electrical discharge machining are preliminarily revealed,which include inter-electrode current climbing up,thermal stress erosion being dominant in the discharge erosion and polarity effect required to be analyzed in depth.