Strain-rate cycling tests associated with the oscillation were carried out at 80 to 240K for two kinds of single crystals: quenched and annealed specimens of KCl:Sr2+ (0.050 mol% in the melt). The following three results were mainly found on the basis of linear plots of effective stress vs. temperature and proportionality of temperature vs. activation energy. 1: The force-distance profile, which expresses the interaction between a dislocation and an impurity, cannot be approximated by the Fleischer’s model when I-V (Impurity-Vacancy) dipoles turn into aggregates (at least trimers). 2: Comparing with the quenched specimen, the activation energy for the break away of a dislocation from the impurity becomes small for the annealed one. 3: The critical temperature, ＴＣ, for the annealed specimen is slightly smaller in contrast to that for the quenched one.
moving dislocation
plastic deformation
force-distance profile between a dislocation and an impurity
strain-rate cycling tests
ultrasonic oscillation