Micro-electrochemical machining using multiple tool electrodes

This paper describes a micro-electrochemical machining technique that uses an electrode array to achieve a high throughput in machining. As the machining area becomes larger, the actual rising time of the double layer potential increases because of a decrease in cell impedance. It is difficult to obtain an effective machining potential because of the ultra short pulse duration. To increase the machinable area, individual pulse generators using a serial MOSFET circuit were used. Using this new circuit, a stainless steel workpiece with a thickness of 50 µm was machined by multiple electrodes each with a 77 µm diameter consisting of 30 single shafts. With this equipment it was possible to drill 120 holes in 40 min, resulting in a 30× improvement in throughput compared to single electrodes.