Micro electrochemical machining using electrostatic induction feeding method

This paper describes a micro ECM system using the electrostatic induction feeding method. With this method, since the pulse voltage is coupled to the tool electrode by capacitance, the pulse duration of the electrolytic current is determined by the rise and fall time of the voltage pulse and is thus significantly short, realizing short gap width. A servo feed system was also developed based on the measurement of the gap voltage. Wear of the tungsten tool was negligibly small because of the oxide layer formed on the tool, allowing micro-holes with sharp edges and straight walls to be drilled.