Multi Attribute Decision Making for Determining Optimum Process Parameter in EDC with Si and Cu Mixed Powder Green Compact Electrodes

Abstract

This paper aims at determining optimum operating process parameters influencing multiple responses in Electro Discharge Coating (EDC) process. Combination of Taguchi and FTOPSIS is applied for optimization. Aluminium 6351 alloy is used as substrate and powder metallurgy compact SiC/Cu of mesh size 325 is used as tool electrode. A Taguchi design of experiments is employed to analyze the sensitivity of EDC response parameters like Material Deposition Rate (MDR), Tool Wear Rate (TWR), Surface Roughness (Ra), Layer Thickness (LT) and also Micro-Hardness (MH) by varying process parameters such as compaction load (P), tool composition (C_T), current (I_P) and pulse duration (T_ON). Weight factors of the responses are determined using triangular fuzzy numbers and the most suitable factor level combination were selected by TOPSIS method. A confirmation test is then conducted based on the optimal parameter setting to illustrate the effectiveness of the approach where material deposition rate of 0.6 (mg/min), tool wear rate of 15.132 (mg/min), surface roughness of 2.92 (µm), layer thickness of 85.38 (µm) and micro hardness of 295.15 (HV) have been successfully obtained.