Nanostructural design of superstrong metallic materials by severe plastic deformation processing

Ultrafine-grained (UFG) metallic materials processed by severe plastic deformation (SPD) techniques often exhibit significantly higher strengths than those calculated the well-known Hall-Petch equation. These result from fact that SPD processing not only forms UFG structure but also leads to formation of other nanostructural features, including dislocation substructures, nanotwins and nanosized second-phase precipitations, which further contribute hardening. Moreover, analysis strengthening mechanisms in recent studies demonstrates an important contribution hardening due phenomena related grain boundaries as a non-equilibrium state presence boundary segregations. Herein, principles design for superior strength using are discussed.