Electrical discharge machining using a strip electrode

One of the most significant problems of electrical discharge machining (EDM) is electrode wear, which results in shape errors and low productivity. In this study, a new EDM method using a strip electrode (strip EDM) was developed in order to overcome the wear problem. The strip EDM uses a continuously applied strip electrode that is similar to the wire electrode used in wire EDM. The strip electrode apparatus can be used as a simple shape tool, which is similar to electrical discharge milling (ED-milling). In the suggested strip electrode method, a conductive strip moves on the electrode guide. The worn strip is removed, and the new strip is supplied continuously. Therefore, the tool electrode can be regarded as having no wear during the machining process. The strip EDM promises precise machining without tool wear and can be substituted for a general ED-milling. This method uses a conductive strip made of copper or brass. To estimate the machining performance of the strip EDM, the material removal rate (MRR) and surface quality were investigated according to the machining parameters, such as depth of cut, peak current, and tool materials. The machining results were compared with the results from general ED-milling. In the practical machining study, precise molds with 3D shapes were machined using the strip EDM method.