Energy stored in NaCl crystals during strain hardening

Abstract

The energy stored in NaCl crystals, compressed in the [001] direction at the rates of 5 × 10−4 and 5 × 10−3 s−1, was measured by a special calorimeter. The results are compared with the latent energy of the plastic strain estimated on the base of experimental data on dislocation density and internal stresses determined by the relaxation method. It is shown that not less than 10 to 20% of the deformation work is stored at the stage II of hardening in NaCl crystals, and that a major portion of the stored work (≈90%) is spent on the formation of defects which do not constitute the sources of the long-range stresses. Point defects (vacancies, their clusters) and dislocation dipoles and multipoles are possible defects of the above type. [Russian Text Ignored].