A Review of Electrolytic In-Process Dressing (ELID) Grinding

ELID Grinding, since its introduction over two decades ago, has helped in material removal of hard and difficult-to-cut engineering materials. A gist of the important research milestones on the process has been organized in this report. The hybrid process of ELID Grinding has a simultaneous electrolytic reaction and grinding action. Electrolysis takes place between the conductive anodic wheel and highly conductive cathode in presence of a special electrolyte. The resulting anodic oxide wears off easily to allow efficient grinding. The different parameters involved in electrolysis complicate the mechanism of grinding and makes it significantly different from conventional grinding. Different variants of the process have also been reported, though the basic philosophy of operation is the same as basic ELID. Several authors have also suggested mathematical explanations, among other fundamental studies, that provide further insight. The basic components of the process, machine tool, power supply, grinding wheel, electrode and electrolytes, have also undergone several modifications and developments to deliver better results and suit specific purposes. The process has been successfully applied in stock removal operations for hard and brittle ceramic materials with low grinding forces compared to conventional grinding. Fine finishing of almost all kinds of hard and brittle materials, ranging from hardened steels, BK7 glass, mono-crystalline silicon, silicon carbide, aluminum nitride, silicon nitride etc, has been successfully carried out, to provide high quality surfaces with low sub-surface damage. Finally, discussions on the different stages of evolution of the process have been put forward as a conclusion to the report.