Multi-objective optimization in wire electric discharge machining of Ti-6AL-4v using grey relational analysis for square and circular profiles

In this work, an attempt has been made for optimization of process parameters in Wire Electric Discharge Machining (WEDM) of Ti-6Al-4V while producing square and circular profiles. The input parameters, namely pulse on time, pulse off time, peak current and servo voltage, were considered to study the responses cutting speed (CS) and surface roughness (SR). Each input parameter was set at three levels. Experiments were conducted as per central composite face (CCF) centered design. Based upon the experimental data, Gray relational analysis (GRA), a multi-objective optimization technique has been employed to find the best level of process parameters to optimize the machining profiles. Analysis of variance (ANOVA) has been conducted for investigating the effect of process parameters on overall machining performance. Finally, it was identified that the process parameters such as pulse on time, current and voltage have more impact on the square and circular profiles.