Technology and research developments in powder mixed electric discharge machining (PMEDM)

Powder mixed electric discharge machining (PMEDM) is one of the recent innovations for the enhancement of capabilities of EDM process. In PMEDM, the electrically conductive powder is mixed in the dielectric of EDM, which reduces the insulating strength of the dielectric fluid and increases the spark gap between the tool and workpiece. As a result, the process becomes more stable, thereby, improving the material removal rate (MRR) and surface finish. Moreover, the surface develops high resistance to corrosion and abrasion. This paper presents a tutorial introduction, comprehensive history and review of research work carried out in the area of PMEDM. The machining mechanism, current issues, applications and observations are also discussed.