Abstract
This paper discribes a new method for micro-EDM drilling which utilizes the wear of a rod electrode. In this method, the polality of the rod electrode is positive, and the rotating rod electrode is fed into the block electrode with a feed rate of several tens times higher than the normal one. Since the circumferential region of the rod electrode wears with a much higher rate than the central region, the end of the rod electrode is sharpened in a few minutes. At the same time, a cone-like micro-hole with sharp bottom shape is generated in the block electrode automatically. This method is available for various kinds of steel materials and any electrode diameter size. It was also found that, when many holes are machined using the same electrode, the electrode shape was regenerated with an excellent repeatability and holls were processed efficiently.
