Low-frequency acoustic properties of kliso₄ crystal at high temperatures

Abstract

The low-frequency internal friction and shear modulus of KLiSO₄ crystal have been studied by an inverse torsion pendulum technique over the temperature range from 300 K to 1000 K. An anomalous behaviour of acoustic properties near 712 K and 948 K related to phase transitions was observed. A strong influence of domain dynamics on the mechanical properties near the phase transitions and in the ferroelastic phase was revealed. The influence is caused by the anisotropy of the mechanical losses as well as a dependence of the internal friction and shear modulus on the experimental conditions and the thermal history

Key Words:

• Phase transition
• ferroelastic
• inverted torsion pendulum