Influence of an electric field on the amplitude dependence of internal friction of alkali-halide crystals at low amplitudes

Abstract

Application of an electric field of intensity 105–106V·m−1 to alkali-halide crystal specimens results in the appearance of an amplitude dependence of the internal friction (IF) in the low amplitude domain of the relative deformation ɛ∼10−7–10−6, where the amplitude dependence of the IF has a peak. A physical model is proposed that is based on the assumption of shifting of the dislocation under the action of the electric field into a new less secure equilibrium position. The growing and decreasing branches of the IF peak are described within the framework of this model. The question of the amplitude dependence of dynamic IF losses is discussed.