www.ijsrp.org An Overview of Additive mixed EDM

Abstract- The objective of this paper is to understand various trends of Electrical discharge machining (EDM) has been widely used as a removal process to produce parts, dies and molds for several decades. In recent years, the surface modification for hardening and depositing some functional materials by EDM has been studied [1].The development of the super tough electrical conductive material such as carbides, stainless steel, nitralloy etc. resulted in development of the nontraditional machining processes. These materials are difficult to machine by conventional machining process & have wide range of applications in industry. In EDM thermal energy is used to machine all electrical conductive materials of any hardness & toughness. Since there is no direct contact between the tool electrode & work piece in EDM, machining defects like mechanical stresses, clattering & vibration do not create problem during machining [2]. In spite of remarkable advantages of the process, disadvantages like poor surface finish and low volumetric material removal limits its use in the industry. In the past few years, Additive mixed Electric Discharge Machining (AEDM) emerges as new technique to enhance process capabilities. In this process, a suitable material in fine powder form (aluminum, chromium, graphite, copper, or silicon carbide, etc.) is mixed into the dielectric fluid of EDM. The spark gap is filled up with additive particles. The added powder significantly affects the performance of EDM process. The electrically conductive powder reduces the insulating strength of the dielectric fluid and increases the spark gap distance between the tool electrode and work piece. As a result, the process becomes more stable, thereby improving machining rate (MR) and surface finish