Multi-objective Optimization of Titanium Alloy through Orthogonal Array and Grey Relational Analysis in WEDM

Wire electro discharge machining (WEDM) operations are dynamic in nature and process responses are related with simultaneous variation of parameters during experiments. To make the process reliable and to study the effects of the process parameters on different responses such as surface roughness (Ra), cutting rate and material removal rate (MRR), attempts have been made to carry out experiments considering the WEDM process parameters. Taguchi method, which is a design of experiments (DoE) method, has been applied to the present experiment followed by Grey Relational Analysis. The signals to noise (S/N) ratio plots are analyzed to study the effect of the process parameters. The adequacy of the above analysis has been tested through the implementation analysis of variance (ANOVA). Next, multi-objective optimization of the response analysis is performed. As the Taguchi methodology is unable to perform multi-objective optimization of the response characteristics, combined approach of orthogonal array and Grey Relational Analysis (GRA) are carried out. Optimal combination of process parameters has been proposed in the machining of titanium alloy in order to achieve minimum surface roughness (Ra), higher cutting rate (CR) and higher material removal rate (MRR). Finally, confirmation tests are carried out to verify the findings.