Nano electrical discharge machining – the outlook, challenges, and opportunities

Emerging trends toward miniaturization and growing demands have led to fabricate the nanofeatures size product for electronics, robotics, aeronautics, biomedical, automobile, and Bio-MEMS sectors. This article investigates an approach to downsize the resolution limits of EDM to nanometric scale, bridging the gap between micro and nanoscale machining considering the thermal impact of electrical discharge. Nano-EDM technology may offer nanosized features, for instance, complex 3D nano-grooves, nanocavities, nanopores, nanotools, nano-painless needles for drug delivery, etc. It is somewhat difficult in any other non-conventional process for electrically conducting alloys having poor machinability. The article identified research issues and perspective solutions for the advancement of nano-EDM technology. The research gap, constraints, and opportunities for future research activities are critically examined through state-of-the-art knowledge. The characterization of features that can be made only by nano-EDM is also highlighted along with their innovative application. The impact of advancements in pulse power technology upon the realization of nano-EDM is briefly reviewed. Moreover, various numerical and simulation approaches along with recent optimization techniques have been demonstrated at the end to understand the continuum mechanics of nano-EDM at the atomic level. Finally, promising future research directions in nano-EDM are emphasized and highlighted.