Assessing the Influence of Surfactant and B4C Powder Mixed in Dielectric Fluid on EDM of Titanium Alloy

The aim of the present investigation is to optimize process parameters by mixing various additives in dielectric fluid on EDM of Ti-6Al-4V alloy using Taguchi technique. Span20 surfactant and B4C powder are considered as additives. Span20 surfactant mixed in dielectric fluid degrades the agglomeration of tar debris and powder particles. It also improves the discharge gap and breakdown strength. Five input process parameters were selected, viz. discharge current (I-p), pulse on time (T-on), pulse off time (T-off), B4C powder concentration (B4C Con.) and surfactant concentration (Surf Con.) and varied to explore their performances on Material Removal Rate (MRR), Surface Roughness (SR) and Recast Layer Thickness (RLT). In this study, Taguchi L-27 Orthogonal Array (OA) was adopted for planning and designing the experiments. It was observed from the experimental results that the additives in dielectric fluid significantly improved MRR, reduced SR and RLT. Analysis of Variance (ANOVA) test has identified that I-p, T-on and Surf con., are important process parameters affecting MRR and SR; I-p, T-on, Surf con., and B4C con., were highly relevant process parameters influencing RLT. An empirical expression for MRR, SR and RLT was developed by using statistical software. Additionally, surface modification was studied at optimized EDM conditions by using Scanning Electron Microscope (SEM) micrographs.