On the basis of the relative curve of strain-rate sensitivity and stress decrement due to oscillation, the values of the enthalpy (ΔH(Tc )＝0.79 eV) and the Gibbs free energy of activation ( 0 ΔG ＝0.39 eV) for the breakaway of the dislocation from the impurity were obtained for KCl:Sr2+ single crystals. ΔH(Tc) and ΔG 0 correspond to the activation energy for overcoming the strain field around the I-V (Impurity-Vacancy) dipole by a dislocation without an applied stress. The critical temperature, Tc , at which the effective stress is zero was previously determined to be 289 K.
activation energy
dislocation
relative curve of strain-rate sensitivity and stress decrement