Statistical and surface metallurgical study during electric discharge machining of Ti-6Al-4V

Titanium alloy (Ti-6Al-4V) is applicable in wide variety of engineering applications due to their attractive and superior properties. However inspite of these properties, they are considered as difficult-to-machine materials because of low heat dissipation, greater tool wear, higher residual stress after machining, severe microstructure alteration and poor surface quality. Hence an attempt has been made to study the statistics and surface metallurgy during electric discharge machining of Ti-6Al-4V in this present paper. The current interest of this paper is to determine the optimum machining conditions for Ti-6Al-4V using statistical tool on Material removal rate (MRR) and Electrode wear (EW) by varying Peak Current (A), Pulse on time (μs), Pulse off time (μs) and spark gap (mm) based on Taguchi's design of experiments and generation of second order model for MRR using Response Surface Methodology. Finally layer formation, surface metallurgy and electrode wear during machining of Ti-6Al-4V has been investigated using Scanning Electron Microscope and Energy dispersive spectrometer.