Authors: Milan Kumar Das; Kaushik Kumar; Tapan Kr. Barman; Prasanta Sahoo
Addresses: Department of Mechanical Engineering, Jadavpur University, Kolkata 700032, India ' Department of Mechanical Engineering, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835215, India ' Department of Mechanical Engineering, Jadavpur University, Kolkata 700032, India ' Department of Mechanical Engineering, Jadavpur University, Kolkata 700032, India
Abstract: This paper presents an experimental study of material removal rate (MRR) and roughness characteristics in electrical discharge machining (EDM) of EN 31 tool steel. Experiments are carried out by utilising the combination of four process parameters viz. pulse on time, pulse off time, discharge current and voltage based on L27 Taguchi orthogonal array. Multi-response optimisation of EDM process parameters is done with respect to MRR and five different surface roughness characteristics based on Taguchi method coupled with grey relational analysis. Analysis of variance (ANOVA) is performed and it is observed that current is the significant process parameter that affects the responses. Optimal setting has been verified through confirmation test and the result shows a good agreement with the predicted value. This indicates utility of the grey-Taguchi technique as a multi-objective optimiser in the field of EDM. Also, the surface morphology is studied with the help of scanning electron microscopy.
Keywords: electrical discharge machining; EDM; electro-discharge machining; material removal rate; MRR; surface roughness; Taguchi methods; grey relational analysis; GRA; multi-response optimisation; surface quality; tool steel; pulse on time; pulse off time; discharge current; voltage; orthogonal array; analysis of variance; ANOVA; surface morphology.
International Journal of Machining and Machinability of Materials, 2014 Vol.15 No.3/4, pp.235 - 362
Received: 17 Jul 2013
Accepted: 06 Dec 2013
Published online: 13 May 2014 *