Multi-response optimization and modeling of trim cut WEDM operation of commercially pure titanium (CPTi) considering multiple user's preferences

Abstract

In this research work, development of a multi response optimization technique has been undertaken, using traditional utility method in conjunction with the weight assignment concept (for multiple customer's priorities) in trim cut wire electrical discharge machining (WEDM). Pure titanium has been selected as work material for experimentation. The effect of key process parameters such a wire type (zinc coated and uncoated brass wire), pulse on time (TON), pulse off time (TOFF), peak current (IP), wire feed (WF), servo voltage (SV) and wire offset (WOFF) were investigated on material removal rate (MRR), surface roughness and wire weight consumption (eroded weight of wire after machining) in finish cut WEDM operation. Two different types of wire electrodes were taken for experimental research (uncoated, zinc coated). Further, the variation of the MRR was modeled semi-empirically through dimensional analysis. The developed model is mechanistic, as it can be used by the machinists to predict the MRR over a wide range of input parameters. The optimization of multiple responses has been done for satisfying the priorities of multiple users, in contrast to the traditional multi-response techniques where the optimized process setting is realized without giving any attention to the priorities of different users.