Parametric optimization of EDM process for Inconel 825 using GRA and PCA approach

Abstract

Parametric optimization of Electric Discharge Machining (EDM) assumes more challenge while machining newer materials for the best yield particularly used in the field of medical, marines and aerospace. In most cases, one methodology/approach does not provide satisfactory results as EDM is a very difficult process. Combination of two or more techniques has been quite successful to solve multi-objective optimization problems. This paper employs a combination of grey relational analysis (GRA) and principal component analysis (PCA) as a multi-objective optimization technique to optimize the process input parameters during EDM of Inconel 825. Experiments were designed by Taguchi’s L36 orthogonal array (OA) for seven input parameters and three performance measures. The optimal combination of EDM parameters is determined using GRA. Then, PCA is adopted to find out the weighting values corresponding to various performance measures. Consideration of two different dielectric fluids, work piece material i.e. Inconel 825 and three different electrode materials is the novelty of this work. Finally, the results are validated by running confirmatory tests. A significant enhancement in performance characteristics has been obtained and reported.