Application of Taguchi methods and ANOVA in optimization of process parameters for metal removal rate in electrochemical machining of Al/5%SiC composites

Metal matrix composites (MMCs) are now gaining their usage in aerospace, automotive and biomedical industries because of their inherent properties like high strength to weight ratio, low wear rate etc. To machine these types of materials conventional machining methods are unsuitable because of high tool wear and tooling cost. Electrochemical Machining (ECM) is one of the important non-traditional machining processes, which is used for machining of electrically conducting, difficult-to-machine materials and intricate profiles. In the present work LM6 Al/5%SiC composites, which are fabricated by stir casting route, were machined by ECM process. The influence of the various process parameters, i.e. voltage, feed rate and electrolyte concentration on the predominant machining criteria, i.e. the metal removal rate (MRR) was studied. The settings of the process parameters were determined by using Taguchi’s experimental design method. Orthogonal arrays of Taguchi, the signal-to-noise (S/N) ratio, the analysis of variance (ANOVA), and regression analyses are employed to find the optimal process parameter levels and to analyze the effect of these parameters on metal removal rate values. Confirmation test with the optimal levels of machining parameters was carried out in order to illustrate the effectiveness of the Taguchi optimization method.