Effects of Preheating Electrolyte in Micro ECDM Process

Abstract

ECDM is a hybrid machining process with enormous potential in machining both conducting & non conducting materials. Present paper focuses on determining the effects of preheating the electrolyte in ECDM process experimentally. Through detailed experimental study, it was found that temperature of electrolyte plays a major role in Material Removal Rate (MRR) and Heat Affected Zone (HAZ) formation.In this work, NaOH was chosen as the electrolyte and was heated to various temperature ranges. Micro features were then machined on the Poly Propylene (PP) work piece and the effect on micro structure formation was analysed. It was found that higher temperature produces spark reduction but causes an increase in heat affected zones in PP. SEM images were used to study the micro features generated on PP. An experimental plan based on Taguchi’s L32orthogonal array was chosen. The machining rate was found to improve with gradual increase in temperature. Beyond certain level, temperature was found to have adverse effects on the properties of PP. An optimum temperature range was calculated in order to carry out the machining at a faster rate without destruction of micro-features.