Micro-EDM Process for Tool-based Compound Micromachining

Abstract

This study aims to develop micro-EDM process for tool-based compound micromachining for machining at the lower boundary of micromachining domain between 5?m ~50?m. A universal multi-process machine tool capable of performing compound micromachining processes has been evaluated and the need for implementation of RC (relaxation circuit) power supply for very small discharge energy has been identified. A model for the RLC network of RC power supply has been proposed from theoretical analysis of micro-EDM plasma properties which guided the development of a RC power supply for very low discharge energy down to ~37nJ. With further improvement in gap control, implementation of 3D micro-EDM milling and techniques for straight electrode fabrication; several shapes and features below 20?m has been machined by micro-EDM process. The developed platform has been utilized for exploration of novel compound micromachining techniques for successful machining of micro-slots and micro-shafts by combining micro-EDM, micro-turning and micro-milling processes.