Abstract
Nanostructured materials with extremely fine grain sizes, typically less than 100 nm, have been shown to exhibit extremely high strength and hardness, increased diffusivity, useful sintering characteristics, and other unusual properties. Significant developments have taken place in recent years in trying to achieve high strength and ductility at the same time. New and potential applications are also being sought after. Several commercial ventures have also started (estimated to be around 1000 in different parts of the world). This overview will present the recent developments in our understanding of the mechanical behavior and molecular dynamics simulation studies, highlight the present unresolved issues, and discuss some of the promising applications for these novel and exciting materials.