Dynamic recovery and stress relaxation kinetics in crystals at low and high homologous temperatures

Abstract

Experiments on stress relaxation revealed that, in NaCl crystals with a surface layer damaged by grinding, plastic flow at a low homologous temperature T/T M=0.28 (T M is the melting point) and with total deformation far from stage III on the work-hardening curve occurs with a noticeable contribution from dynamic recovery processes, which is typical of higher temperatures. The kinetics of relaxation of effective and long-range stresses is studied. The results are compared with the behavior of unground NaCl crystals at the same temperature, as well as with the behavior of polycrystalline In-4.3 at. % Cd samples deformed at T/T M=0.7, for which the dynamic recovery is complete and is manifested not only in experiments on relaxation but also in the shape of the deformation curves.