A multi-objective optimization using a combined approach of principal component analysis and TOPSIS during electric discharge machining of H-11 die steel using P/M processed Cu-Cr-Ni metal matrix composite

摘要

The present experimental investigation deals with the electric discharge machining of H-11 die steel using metal matrix composite (MMC) as tool electrode. The MMC was prepared using powder metallurgy (P/M) route at a sintering temperature of 800°C. A comparative study has been made using conventional Cu and powder metallurgy (P/M) processed Cu-Cr-Ni MMC as tool electrode. The effect of input parameters like peak current (Ip), pulse-on-time (Ton), duty cycle (DC) and gap voltage (Vg) on response variables like material removal rate (MRR), tool wear rate (TWR), surface roughness (SR) and diametral overcut (DOC) have been analyzed. Multi-objective optimization has been done using a hybrid method of principal component analysis (PCA) and technique for order preference by similarity to ideal solution (TOPSIS) to obtain the optimal set of parameters for copper and Cu-Cr-Ni tool. The optimum parameter setting for copper tool was found to be at Ip=3A, Ton=200μs, DC=9, Vg=50V and for Cu-Cr-Ni tool was found to be at Ip=6A, Ton=150μs, DC=9, Vg=30V.