Machinability Analysis of Composite Electrode Produced by Spark Plasma Sintering Process during Electro-Discharge Machining of Titanium Alloy

The present experimental work aims at fabricating composite tool electrode made of copper, tungsten and boron carbide using spark plasma sintering process. Specifically, the study focuses on assessment of its performance during electro-discharge machining of titanium alloy. The machining parameters considered in this work are peak current, pulse duration and pulse cycle along with composition of tool electrode material (weight percentage of tungsten and boron carbide). In order to evaluate the performance of spark plasma sintered tool electrode, the machining characteristics considered are material removal rate, electrode wear rate, surface roughness, surface crack density, white layer thickness and micro-hardness of the machined surface. The energy dispersive x-ray spectrometry of the machined surface reveals that transfer of electrode elements onto the machined surface occurs with increase in the percentage of carbon and oxygen on it. X-ray diffraction of machined surface shows formation of metallic carbides (Al₃B₄₈C₂, VC, TiC, W₂B and W₆C_2.54) on it causing increase in micro-hardness of the machined surface and formation of recast layer or white layer.