Micro-Electro-Discharge Machining (micro-EDM) is gaining in popularity within the micro- and meso-scale machining community. The process is very well suited to machining small, intricate features in any type of conductive material because material removal is by melting and vaporization rather than by shearing, as in traditional machining. In this study, the maount of material removed by a single micro-EDM discharge was measured in various pure metals over a variety of energies characteristic of typical micro-EDM processes. A unique experimental setup allowed for creation of single micro-EDM discharges and the resulting craters were examined using a scanning white-light interfereometer. The results show a linear relationship between the volume of material removed and the applied energy of the discharge, and a power law relationship with an exponent of 0.33 between the diameters of the craters and the applied energy. Thermal models used to predict material removal by EDM were found to be inaccurate at the low energies of micro-EDM, therefore a new, spherical heat source model is proposed. No lower bound on material removal was observed, and it is proposed that the micro-EDM process is bound by existing technology rather than any physical limitations.
Proceedings of the ASPE 21st Annual meeting
October 15-20, 2006
ASPE 21st Annual Meeting
cutting forces, machining process optimization, precision engineering