Experimental investigation on electro discharge machining of Ti6Al4V alloy
Arka Mondal, Prithwiraj Roy, S. Mitra
Abstract
Ti6Al4V is an alpha-beta titanium alloy, extensively used in aerospace engineering, gas turbines, also in other industries. Features like high strength to weight ratio, high corrosive resistance have made it very much useful in industries. EDM is one of the most popular and powerful non-conventional machining process, capable of machining this type of difficult-to-machine conductive material. The main drawback of EDM is adhesion of debris in between electrodes which disturbs stability of the spark and affects machining rate and quality of machining. In the present research, this problem has been addressed by modification of tool shape, making the face of the tool tapered. Here, full factorial set of experiments has been carried out to investigate the effect of various process parameters, like gap current, pulse-on-time, duty cycle and effect of tapered tool, on material removal rate and tool wear rate. It has been observed that using tapered tool machining rate has been improved, but tool wear rate has been increased using tapered tool. In this paper, SEM photograph of machined hole has been inspected and it is observed that the thickness of the recast layer is smaller and uniform using tapered tool.