An experimental investigation of single and multi-tool micro-EDM

Abstract

Electro Discharge Machining (EDM) is potentially an important and cost effective non-conventional machining process for the fabrication of micro-components. However, a number of issues remain to be solved before micro-EDM can become a reliable process. Because of the stochastic nature of the process, the parameters are still at development stage and their effects on performance measures are yet to be clarified. It is necessary to know, in advance, properties relating to these effects by means of experimental investigation by taking into account machining characteristics such as spark gap, material removal rate, surface quality and also tool wear. In view of this on going challenge, a series of rigorous experiments were conducted during this study to identify the optimum parameters and the machining trends of die-sinking micro-EDM with both single and multi-tools. The main parameters affecting the end results of the process were identified and optimal parameter ranges for voltage, current, pulse on time, pulse off time, short and open were found. The effects of different types of pulse generators (transistor type and RC type) were also investigated.