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The effects of the applied stress τ and temperature on the mobility of edge and screw dislocations in NaCl crystals are investigated under high hydrostatic pressure. The critical shear stress of these crystals is obtained to τs = (40 ± 6) g/mm2. Fresh dislocations are put into starting position by striking. A sample is loaded in the pressure chamber according to the scheme for the four‐point kink. The temperature is varied from +20 up to 150 °C. The results show the decrease of the dislocation mobility under pressure. The velocity ratio of edge and screw dislocations is shown to decrease as the pressure increases. The experimental dependences are in good agreement with the given theoretical analysis which suggests the observed effects to be connected with both, the enhancement of the interaction between dislocations and the local barriers under hydrostatic pressure and the increase of their self energies.

Evidence of current induced structural and conduction anisotropy was experimentally established in scandia‐stabilized zirconia ceramics. It was found that these effects are observed only when the material is in the rhombohedral phase. It was shown using conductivity measurements and X‐ray phase analysis that anisotropic behavior of polycrystalline ZrO2‐Sc2O3 ceramics is induced by a low‐amplitude alternating current in the temperature range corresponding to a rhombohedral‐to‐cubic phase transition.

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