This book discusses in detail about grain refinement by various severe plastic deformation processes such as equal channel angular pressing, high pressure torsion, twist extrusion and so forth. It also deals with grain refinement mechanism, influence of process parameters on the properties of the fabricated micro/nano material, thermal stability, commercialised nanostructured metals and alloys produced by severe plastic deformation techniques and associated challenges. Includes individual severe plastic deformation processes and its engineering features in detailDiscusses commercialised nanostructured metals and alloys produced by severe plastic deformation and challengesDeals with grain refinement mechanism, influence of process parameters on the properties of the fabricated micro/nano materialExplores pertinent functional propertiesGives comprehensive view of the successful application of severe plastic deformationThis book is aimed at graduate students and researchers in materials science, mechanics, and manufacturing engineering.