Current pattern of plastic deformation stages

A review of current concepts of strain hardening stages in metallic materials upon active deformation is presented. By now, five stages of the stress () — strain () dependence reliably have been identified. These stages differ by the strain hardening coefficient = d/d. There are also some data on stage VI. In the paper, the role of substructural transformations in the change of strain hardening stages is discussed, the factors complicating the deformation stage pattern are analyzed, and the effect of grain size on stages of strain hardening is examined.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 90–98, August, 2004.