Modelling and Optimization of Al-SiC MMC through EDM Process Using Copper and Brass Electrodes

Extensive investigation done on machinability of aluminium/10% silicon carbide metal matrix composite (Al/SiC MMC) with copper and brass electrodes in die-sinking electrical discharge machining (EDM) is reported in the present study. Experiments are performed as per the Box-Behnken design of RSM to study the two performance characteristics i.e. electrode wear ratio (EWR) and material removal rate (MRR) with the five input machining parameters like, low voltage current, high voltage current, pulse off time, pulse on time and flushing pressure. Quadratic regression models are developed for the individual responses and multi-objective particle swarm optimisation (MOPSO) algorithm is employed to find the optimal process parameter settings. Finally, a novel MOPSO algorithm has been suggested for simultaneous optimisation of multiple responses which presents valuable information for governing the machining parameters to enhance accuracy of the electrical discharge machined parts and a confirmation test is performed at the optimized parameter setting for copper and brass electrodes respectively to validate the result. The scanning electron microscope (SEM) also used to investigate the surface characteristics of the machined surface. (C) 2017 Elsevier Ltd. All rights reserved.