Examination and Optimization of Machining Parameters in Electrical Discharge Machining of UNS T30407 Steel

Electrical discharge machining (EDM) is a non-conventional process utilized for machining electrically conductive materials which cannot be machined by conventional processes. This paper is focused on modeling and optimization in electrical discharge machining (EDM) of UNS T30407 steel. The variables such as pulse on time (Ton), pulse off time (Toff), and current will influence the material removal rate (MRR) and surface roughness (Ra) which were taken as response variables. Experimental data were collected as per the central composite design (CCD) matrix of response surface methodology (RSM) approach and mathematical models have been developed for both the response variables. The analysis of variance (ANOVA) was employed to determine the significant machining parameters and optimize the input parameters for both the responses (MRR and Ra). The statistical adequacy of the models is tested with the help of ANOVA. The optimum parametric combination for maximum MRR and smaller Ra (highest surface finish) was found. The surface characteristics of the machined surface were investigated by a scanning electron microscope (SEM).