Piecewise Model with Two Overlapped Stages for Structure Formation and Hardening upon High-Pressure Torsion

The evolution of metals micro/nano-structure upon severe plastic deformation (SPD) is still far to be theoretically explained, while experimental datasets are persistently growing. Major problem associated with understanding SPD a synergetic effect several competing processes which alter material structure. In this paper we propose model reveal, as free-fitting parameters, strain breakpoints where predominantly one mechanism determines the in materials from hardness vs true data. applied analyse data for pure polycrystalline iron and two distinctive have been revealed.