Surface Modification by Electro-Discharge Coating (EDC) with WC-Cu P/M Electrode Tool

Abstract

Electro discharge machining (EDM) is a prominent non-traditional machining process. A very common aspect of EDM is surface modification which is possible by the use of powdered metallurgy green compact and sintered electrode which creates a hard and wear resistant layer on the workpiece. The process is carried out with the reversal of polarity and is known as electro-discharge coating (EDC). Here we have used Tungsten Carbide (WC) and Copper (Cu) as coating material. Effect of various process parameters in EDM and powder metallurgy compaction process such as current, compaction pressure, composition of powder mixture on material transfer rate and tool wear rate have been investigated. We studied the microstructure of the layers in the coating by SEM (Scanning Electron Microscope) while the compounds present in the coating were analyzed by XRD (X-Ray Diffraction) technique. The hardness of the coating was also being analyzed by Vickers Micro hardness Tester.