Features of resonance absorption of longitudinal ultrasound in strained crystals KBr at temperature variations

Abstract

The frequency dependence of a dislocation damping decrement of ultrasound in KBr single crystals preliminary strained up to 1 % in the temperature range 77-300 K and frequency range 7.5-217.5 MHz has been investigated. The temperature course of the phonon viscosity coefficient B was determined, which is agreed both with the theory and experimental literature data. The effect of temperature-induced changes in the dislocation segment length on parameters of the resonance maximum and dynamic drag of dislocations by phonons has been revealed and considered.