(BQ) The article presents an idea about the effect of the various input process parameters like Pulse ON time, Pulse OFF time, Discharge Current and Voltage over the Surface Roughness for an EN41 material. Here, 5 different output parameters concerned with surface roughness like Ra, Rq, Rsk, Rku and Rsm are taken and optimized accordingly, using the Grey-Taguchi method. | Available online at ScienceDirect Procedia Materials Science 6 (2014) 383 – 390 3rd International Conference on Materials Processing and Characterisation (ICMPC 2014) Effect and Optimization of various Machine Process Parameters on the Surface Roughness in EDM for an EN41 Material using Greytool steel Taguchi Vikasa, Apurba Kumar Royb, Kaushik Kumarb* b a Research Scholar, Birla Institute of Technology, Mesra, Ranchi-835215, INDIA Associate Professor, Birla Institute of Technology, Mesra, Ranchi-835215, INDIA Abstract The article presents an idea about the effect of the various input process parameters like Pulse ON time, Pulse OFF time, Discharge Current and Voltage over the Surface Roughness for an EN41 material. Here, 5 different output parameters concerned with surface roughness like Ra, Rq, Rsk, Rku and Rsm are taken and optimized accordingly, using the Grey-Taguchi method. The Grey-Taguchi method used in the article considers an L27 orthogonal array, which uses a different combination of the 4-input parameters to obtain an optimized value of the surface roughness for EN41 material. The 5 different output values of the surface roughness are calibrated into a single value (. Grade) by calculating their normalized, Δ and ξ values .On the basis of their Grade, the S/N ratio is obtained and accordingly the ANOVA table is generated. It was found that the Current had larger impact over the Surface Roughness value, followed by the Voltage. The experimental results thus, obtained were compared with the theoretical results and they were found very close to one another. © 2014 Elsevier Ltd. This is an open access article under the CC BY-NC-ND license © 2014 The Authors. Published by Elsevier Ltd. (). the Gokaraju Rangaraju Institute of Engineering and Technology (GRIET). Selection and peer-review under responsibility of Selection and peer review under responsibility of the Gokaraju Rangaraju