绝缘陶瓷往复走丝线切割加工放电状态检测方法

Discharging Status Distinguish Method on Machining Si_3N_4 by HS-WEDM

绝缘陶瓷材料在工程中应用广泛,但由于其脆硬性,用普通方法很难加工。通过辅助电极利用往复走丝电火花线切割的方法对绝缘陶瓷氮化硅作了加工实验研究,并用普通金属与电阻串联的方法进行了仿绝缘陶瓷氮化硅加工实验研究。对实验数据进行了分析,根据导电层对维持电压的影响情况,将导电层分为良、中、差3个等级,并设计出一种专门用于绝缘陶瓷碳化硅往复走丝线切割加工放电状态检测的方法,能区分出3种处于不同导电层等级状况下的正常放电、空载以及短路等5种放电状态。

Advanced engineering ceramics are more and more widely employed in modern industries. But the ceramics is very hard to machining through the traditional machining method for their excellent mechanical properties such as high hardness, high compressive strength. This paper investigates the high speed wire electrical discharge machining （HS-WEDM） of Si3 N4-based ceramics by assisting electrode method, and one novel circuit is designed to imitate the discharging status of the insulating ceramics machining. Comparing the results of imitated circuit with the real ceramics machining, this paper proposed that the carbon layer is defined in three degrees： good, middling and bad. A detection circuitry, which can distinguish five discharging statuses： short, open and three special discharging statuses under different degrees of carbon layer.