Abstract

Electrical Discharge Machining (EDM) is a Non conventional machining method which has many years of history. EDM was developed as an accurate machining method for hard materials in the starting. Many researches and new methods have been discovered in electrical discharge phenomena in recent years. Smooth and very fine finish machining, modification of mould die on its surface, machining of materials which are insulated are keyed among the methods in the EDM field. These methods are  related with control in the characteristics of surface of the material and with control in motion of the electrode. EDM, also referred as spark machining or spark erosion machining is a directed metal removal process based on the principle effects of erosion of electrical discharges taking place between two electrically conducting materials dipped or immersed in a dielectric fluid medium. EDM process is used by various industries for machining all types of electrically conductive materials such as metallic alloys, some of the ceramics and metals. In this paper, we introduce EDM principle and operation, discuss recent trends and applications, advantages and disadvantages of EDM.