Ultra-Short Pulse ECM using Electrostatic Induction Feeding Method

This paper describes micro electrochemical machining (ECM) using the electrostatic induction feeding method. In ECM, gap distance can be decr eased to several micro meters by using pulse durations shorter than several tens of nano seconds. With the electrostatic induction feeding method which has been developed by the authors, since the pulse power supply is coupled to th e tool electrode by capacitance, the current pulse duration is nearly equal to the rise time and fall time of the pulse voltage regardless of the pulse-on time of the pulse voltage. Thus ultra-short current pulses can easily be obtained without a need to use an expensive ultra-short pulse generator. M achining results of micro-hole drilling with current pulse duration of several ns showed that significantly small side gap of 1 μm could be obtained.