Performance of Additive mixed Electro-Discharge Machining of Inconel 718 Super Alloys

Abstract

In the present work, Performance of Additive mixed Electro-Discharge Machining of Inconel 718 Super Alloys has been attempted. Since, traditional machining routes are inappropriate for ‘difficult-to-cut’ materials (like Inconel 718 super alloys); EDM process has been adapted. In contrast to conventional EDM (no powder); addition of conductive powder particles into the dielectric media has been recommended in literature in order to improve machinability of super alloys. Experiments have been performed by varying peak discharge current and pulse duration; Copper powder (400 Mesh) has been added to the EDM oil (dielectric media). Performance of powder-mixed EDM has been analyzed in terms of material removal efficiency, surface roughness, surface crack density and white layer thickness. EDS and XRD tests have been carried out to understand chemical composition and metallurgical aspects of the machined surface (viz. material migration, phase, extent of grain refinement, formation of intermetallic compounds, residual stress) as compared to ‘as received’ parent material.