SURFACE MODIFICATION BY ELECTRO-DISCHARGE MACHINING USING POWDER METALLURGY ELECTRODE: A REVIEW

Abstract

Since the last two decades, many novel techniques have evolved from electro-discharge machining (EDM). Among them, surface modification is one of the rigorously growing technologies by which surface properties can be enhanced by providing a layer having a thickness up to some microns on the workpiece. Existence of tool material on the machined surface after EDM was observed previously. This attribute of EDM makes it a benchmark in surface modification technology. Surface modification in EDM can be done by using different types of electrodes like solid, powder metallurgy (P/M), brush type, etc. This phenomenon can also be acquired by suspending powder particles into dielectric media. However, P/M electrode gives superior results with less effort and also proves to be economical. In this paper, a review has been made on using P/M electrode in surface modification during EDM. The different types of electrodes for surface modification, development of P/M electrode, types of layers generated and surface roughness improvement are critically analyzed. Also, some scope for future works is suggested here.