Surface Quality Modification Using Powder Metallurgy Processed CuW Electrode During Electric Discharge Machining of Inconel 718

Use of powder metallurgy processed (PM) electrode in electrical discharge machining (EDM) has emerged as an alternate tooling option with a view to impart improved surface properties to the work surface. Preliminary investigation with CuW PM electrode using Taguchi method was done on Inconel 718 to obtain best parameter settings for higher the better surface roughness. In the present work surface micro hardness study and X-ray diffraction (XRD) analysis was performed on the machined surface at the best parameter setting and comparison was done with the surface machined using conventional copper electrode. It was observed that the micro hardness of the machined surface was improved from 380.9 HV of the base metal to 496.7 HV of the surface machined with powder metallurgy processed electrode. XRD analysis revealed the formation of Fe2W3C6 phase on the machined surface causing remarkable improvement in the surface micro hardness.