Investigations on Electric Discharge Machining Performances of AA8011-10wt.% TiO2 Composite using MCDM Approach

Abstract

Abstract This research work describes the optimization of machining parameters in electric discharge machining (EDM) of Al-Fe-Si (AA8011) alloy composite using multi criteria decision making (MCDM) approach. Initially, AA8011 matrix alloy is synthesized with addition of 10wt.% TiO2 particles through stir casting route. Scanning electron microscopy (SEM) was used to taken out the morphology of synthesized composite and it was reveal the inclusions of TiO2 particles uniformly disseminated within the matrix. The machining input parameters such as peak current (Ip), pulse-on time (Ton) and pulse-off time (Toff) were chosen at three levels, whereas the material removal rate (MRR), the surface roughness (SR) and the tool wear rate (TWR) were selected as the output responses. According to the Taguchi’s L9 (33) orthogonal array the machining experiments were conducted by using a brass (Br) electrode. By employing the Order Preference by Similarity to Ideal Preferred Solution (TOPSIS) method, the optimum combination of parameters were determined. Based on the analysis, the peak current (Ip) of 10 amps, pulse-on time (Ton) of 200 µs and pulse-off time (Toff) of 30 µs gives the higher MRR (0.2379 g/min) with lesser SR (3.284 µm) and TWR (0.0258 g/min). ANOVA result reveals that the pulse-on time found to be primary noteworthy factor with a contribution of 50.67%, followed by pulse-off time (32.98%) and peak current (13.12%) respectively. Finally, to validate the experimental results, the verification test was carried out using the optimal level of parameters.