Optimization Of Twr In Edm Machning On H30 Alloys With Graphite Coated Electrodes

Abstract

Electric discharge machining (EDM) is a non-conventional manufacturing process in which electrical discharges are used to obtain a desired shape. A dielectric liquid separates the tool electrode from the workpiece, which allows current discharges to remove material from the workpiece. In order to maintain mould finishing applications, tool wear rate is one of the most critical factors. Electrode developments with promising cost reductions are needed for major contact areas in material removal. This cost can be reduced by using ceramic substances like aluminum that are coated with graphite and attached to polymer inserts. For EDM machining of mould finished components, graphite coated aluminum and copper attached polymer inserts were assessed. The TWR was calculated using a pre-machined H30 mold base with a graphite coating of 0.8mm thick on both materials. As compared with graphite electrodes attached to aluminium copper, graphite coated electrodes returned better results by 15%.