New studies of paradox of strength and ductility in nanomaterials

Crystalline materials can be superstrong or ductile, but they rarely exhibit both of these properties at the same time. This is due to the physical nature of their plastic deformation, which is determined by the mobility of dislocations - linear defects of the crystal lattice - in the grain/crystallite interior. This is also true for nanostructured materials with very small grain sizes in the nanometric range. At the same time, in recent years, a number of original approaches have been developed and proposed to achieve high strength and ductility of nanomaterials, particularly, processed by severe plastic deformation (SPD) techniques. The paper below presents a brief overview of these approaches as well as their physico-mechanical principles put forward as of today.