Experimetnal investigations into the performance of water as dielectric in EDM

Abstract In the present work, machining characteristics of distilled water, tap water and a mixture of 25% tap and 75% distilled water when used as dielectric fluid in EDM are reported. Two different tool materials, viz., brass and copper with positive and negative polarities have been used to machine low carbon steel workpieces at low current densities. All the experiments have been planned statistically and response surface equations for metal removal rate, relative electrode wear and surface roughness have been obtained. The best machining rates have been achieved with the tap water and a special feature of machining in water was the possibility of achieving zero electrode wear specially when copper tools with negative polarities were used.