Optimization of Process Parameters in WEDM of EN-31 Alloy Steel using Taguchi Technique and TOPSIS

Optimization of parameters in any process is vital to survive in the present competitive era as it helps to meet out the quality, functional and economical requirement of the product in the best possible way. In this work, TOPSIS (Techniques for Order Preference by Similarity to Ideal Solution) method is combined with Taguchi’s technique to solve a multi objective optimization problem in Wire-electrical discharge machining (WEDM) of EN-31 alloy steel. Process information was gathered by Taguchi’s L27 orthogonal array to study the effect of six input parameters on four responses. TOPSIS has been used to convert multiple responses to a response called as Multi-Performance Characteristic Index (MPCI). This MPCI was then optimized by Taguchi method. ANOVA revealed that pulse off time (41.38%) was the most significant parameter followed by the servo feed (26.80%) and pulse-on-time (15.10%) whereas the effect of wire feed, wire tension and spark gap set voltage is negligible. Further, the confirmation experiment with optimal parameters confirmed that the targeted multi-performance characteristic was significantly improved to achieve more desirable levels.