On the nature of ultrahigh plastic (Megaplastic) strain

The features of structural transformations occurring at ultrahigh plastic strains, which are proposed to refer to as gigascopic, have been analyzed. It is shown that, during such deformation, additional channels of elastic energy dissipation must be effectively implemented. It is concluded that structural changes are characterized by certain cyclicity. A specific route of structural rearrangements is determined by temperature, the height of the Peierls barrier for dislocations and their ability of diffusive rearranging, and the difference in the free energies of the crystalline and amorphous states.