抄録
In this paper we investigate the scattered debris generated in a bubble during a pulse discharge in order to discuss the material removal phenomena in the EDM process. A single pulse discharge is generated between a parallel gap and the motion of the scattered debris as well as the bubble expansion is observed using a high-speed video camera. It is found for the case of discharge in a bubble that material removal occurs during the discharge duration but does not occur after the discharge duration, whereas material removal occurs during and after the discharge duration for the case of discharge in a dielectric liquid.