Experimental Investigations into Powder-Mixed Electrical Discharge Machining (PMEDM) of HCHCr D2 Die Steel

The purpose of this paper is to present an experimental work attempting to model and optimize the influencing process parameters involved in powder-mixed electrical discharge machining (PMEDM). Looking at available literature it is observed that a lot of work can be done in the field of electric discharge machining related to surface integrity. In this work Aluminum, Silicon and Silicon Carbide fine abrasive powders with particle concentration of 2 gm/l and size of 44 mu m were added into the SEO25 (spark erosion oil) dielectric liquid of electrical discharge machine. The experiments were carried out on experimental set up developed in laboratory. HCHCr D2 die steel and copper was used as work piece and tool electrode materials, respectively. Response surface methodology (RSM), employing a face-centered central composite design for three design variables such as peak current (Ip), pulse on-time (Ton), and powder material was used to assess the process performance. Suitable mathematical models for the response outputs were obtained.