MULTI-RESPONSE OPTIMIZATION OF EDM PERFORMANCE CHARACTERISTICS USING RESPONSE SURFACE METHODOLOGY AND DESIRABILITY FUNCTION

In the present investigation, the experiments were conducted on a CNC Electrical discharge machine for machining of AISI D2 steel with cylindrical copper rods as electrodes to determine the effect of process parameters such as electrode rotation, voltage, current and spark gap on the responses material removal rate (MRR), surface roughness (Ra) and electrode wear rate (EWR) using response surface methodology (RSM).The second order polynomial model in terms of process parameters were developed for the responses on the basis of experimental results and has been validated with Ftest. The adequacy of these models has been tested on the responses with analysis of variance (ANOVA). Finally, to overcome the problem of conflicting nature of responses with single response optimization, multi- response optimization has been carried out using response surface methodology with integration of desirability function. Confirmation experiments are further conducted to validate the results.