Ultrasonic-assisted micro-EDM of deep bores: Process and discharge analysis

Ultrasonic vibration has been found very beneficial for the micro electro discharge machining (ìEDM) of deep microstructures with high aspect ratios. In this study, the discharge properties of ìEDM aided with direct ultrasonic workpiece vibration are analysed and compared to conventional ìEDM machining. It can be shown that not only the number of discharges per second is significantly improved, but also the typical height of the discharge current is differently distributed. The investigation shows that the amount of open circuit states in ìEDM can be noticeably reduced by using ultrasonic vibration assistance.