Optimization of Process Parameters in Electro Discharge Machine Using Standard Deviation, MULTIMOORA and MOOSRA Methods

Abstract

Nowadays in the extremely competitive market, an industrial product should be manufactured in minimum duration with high precision and quality. To attain these, the process parameters are regulated to get the desired output based on the requirement. The process parameters play an important role in defining the surface quality and material removal rate. Electric discharge machine (EDM) is one of the most striking alternative in the industry based on its attributes. Four input parameters, namely voltage, pulse-on time, current and duty cycle, are considered. The effect of these parameters on material removal rate (MRR) and surface roughness (Ra) is studied based on the experimental results. Multi-objective optimization techniques help a decision-maker to select a best alternative from a set of alternatives which have conflicting objectives. In this paper, standard deviation is used to find the relative importance of the attributes. The weights obtained using standard deviation are MRR is 0.53 and Ra is 0.47. Further new multi-objective optimization techniques, namely full multiplicative form of MOORA (MULTIMOORA) and multi-objective optimization based on simple-ratio analysis (MOOSRA), are applied to obtain the optimum process parameters. The process parameters corresponding to run number 6 are voltage 50 units, current 15 units, duty cycle 50 and pulse-on time 100 units, are the best parametric combination to achieve maximum MRR and minimum surface roughness.