Experimental investigation on precision machining of multiple holes by WEDM on Aluminium-6061 using genetic algorithm

Abstract

Aluminum base alloys used in aeronautical applications is machined using WEDM to machine complex profiles with good accuracy and minimum taperness. This present investigation explores wire cut EDM machine tool usage for optimization process variables of Aluminium-6061 alloy. A Sequence of experiments are developed to research the process parameters, effects such a pulse on time—TON, wire feed rate—WFR, pulse off time—TOFF and servo voltage control—SVC on dimensional deviation—DD, Taperness, wire wear rate—WWR and metal removal rate—MRR. Trial runs on Al-6061 are conducted by taguchi design of experiments, a regression equation is developed. Genetic algorithm optimization technique is applied to yield global optimum results for optimizing process variables. Finally, comparison done across experimental results to predicted values for effectiveness 95% of confidence level was obtained. The optimum levels for getting minimum taperness is identified for square geometry are pulse on time—103 µs, pulse off time—59.99 µs, wire feed rate—6.45 mm/min and control of speed—92.52%. For circular geometry the identifications are pulse on time—103 µs, pulse off time—59.99 µs, wire feed rate—7.88 mm/min and control of speed—42.34% for optimum response. The optical microscope conformation test has obtained with satisfactory.