Analysis of mechanism based on two types of pulse generators in micro-EDM using single pulse discharge

Abstract

Micro-electrical discharge machining (micro-EDM) has become an advanced machining technique in recent times. In the micro-EDM process, the power supply unit (PSU) is an important component because of its considerable influence on the machining parameters. Additionally, there are two main types of pulse generators: RC- and transistor-type pulse generators. In this study, a series of novel analyses and experiments featuring the mechanisms of each of the two types of pulse generators were conducted using single discharge pulse. The discharge characteristics of the two types of generators were discussed first. Then, the differences in their discharge channel radii when using the plasma model with single pulse were presented. In addition, their thermal effects were analyzed using the thermal heat model with single pulse. Lastly, a train of related single pulse discharge experiments was carried out using the two different pulse generators with varied simulation parameters in order to observe real phenomena in micro-EDM. The results of experiments were consistent with those of simulations, and the two different pulse generators can be applied to different situations, depending on the machining circumstances, as a result of their different machining characteristics. The findings of this study are expected to help guide the selection of the pulse generator type based on parameter requirements in micro-EDM.