Modeling of a single resistance capacitance pulse discharge in micro-electro discharge machining

Abstract

Micro-EDM (electro discharge machining) is a derived form of EDM process especially evolved for micro-machining. The use of resistance capacitance pulse generator, an advanced controller for machining in smaller interelectrode gaps and with lower discharge energies than in EDM, makes the material removal characteristics of a single discharge in micro-EDM different from that of the EDM. A comprehensive model predicting the material removal in a single discharge in micro-EDM is conceptualized. The model incorporates various phenomena in the prebreakdown period. It considers plasma as a time-variable source of energy to the cathode and anode to evaluate material removal at the electrodes. The plasma temperature and radius of the crater at the cathode (work-piece) predicted using the model were found to agree well with the experimental data in the literature.