Surface evaluation of ED machined 316L stainless steel in TiO2 nano-powder mixed dielectric medium

Abstract

Abstract This paper examines the influence of process parameters in the presence of TiO2 nano-powder mixed electric discharge machining (PMEDM) of 316L stainless steel. Commercial grade tungsten electrode with reverse polarity was used for the current experimentation. The responses were assessed in terms of material removal rate and surface roughness using orthogonal array L18 experimental design. It was observed that the most significant factors enhancing material removal (6.75 mg/min.) were current, voltage and powder mixed dielectric medium. There was negligible tool wear due to low wear rate of tungsten electrode. The surface morphology and chemical composition of machined samples were investigated using scanning electron microscopy and x-ray diffraction techniques. It was found that addition of powder in dielectric intensifies the machining stability and material transfer mechanism.