Study of the formation of reorientation nanobands with the participation of non-dislocation deformation mechanisms

Abstract

Based on the results of electron microscopic studies of strain localization nanobands with a reorientation of the crystal lattice by 90°‹110›, the theoretical study of non-dislocation mechanisms of plastic deformation is conducted. Using the atomic model of martensitic transformations based on a system of cooperative thermal fluctuations of planes in a BCC lattice, the distortion tensor of the reversible martensitic transformation (β±) is estimated. Based on the analysis of the elastically stressed state of nanodipoles of partial disclinations, the rates of the quasi-viscous deformation mode are estimated. It is shown that the propagation rate of a nanodipole of partial disclinations (L˙) in the quasi-viscous mechanism, depending on the activation energy of the migration of point defects (vacancies, interstitial atoms) and the deformation temperature, can reach high values close to the speed of sound in metals.