Experimental investigation and optimization of EDM process parameters for machining of aluminum boron carbide (Al-B4C) composite

This study investigates the effect of electric discharge machining (EDM) process parameters [current, pulse-on time (T-on), pulse-off time (T-off) and electrode material] on material removal rate (MRR), electrode wear rate (EWR) and surface roughness (SR) during machining of aluminum boron carbide (Al-B4C) composite. This article also summarizes a brief literature review related to aluminum metal matrix composites (Al-MMCs) based on different process and response parameters, work and tool material along with their sizes, dielectric fluid and different optimization techniques used. The MMC used in the present work is stir casted using 5% (wt) B4C particles of 50micron size in Al 6061 metal matrix. Taguchi technique is used for the design of experiments (L-9-orthogonal array), while the experimental results are analyzed using analysis of variance (ANOVA). Response table for average value of MRR, EWR and SR shows that current is the most significant factor for MRR and SR, while electrode material is most important for EWR. ANOVA also confirms similar results. It is also observed that the optimum level of process parameters for maximum MRR is A(3)B(1)C(3)D(3), for minimum EWR is A(1)B(2)C(3)D(1), and for SR is A(1)B(3)C(3)D(3).