Milling Tool of Micro-EDM by Ultrasonic Assisted Multi-Axial Wire Electrical Discharge Grinding Processes

Conventional micro EDM milling relies on time-consuming WEDG to achieve acceptable quality of micro tools. In this study, a rotational axis augmented to Wire Electrical Discharge Grinding (WEDG) processes with ultrasonic assistance and its application to EDM micro-milling is reported. On its removing mechanism, a quantitative analysis based upon wire-EDM discharge-angle was proposed to clarify fundamental understanding of such a novel multi-axial machining process. Then, a test on EDM micro-milling with 70 microns of diameter tool is conducted. Its significant effects on improving dressing efficiency and surface integrity of micro tools were verified, and the effectiveness for EDM micro-milling with a screw type of tool was also verified experimentally. Because of its geometric properties, the screw surface contributed to deliver debris from machining region to outsider. Therefore, a better EDM micro-milling configuration may be introduced into the micro-EDM manufacturing field.