Dependence of shear stress of the LiF crystals on concentration of oriented dipoles

Studied was the dependence of shear stress tau of LiF crystals irradiated by γ-rays in the electric field upon the field intensity and the radiation dose. It has been established that the concentration of oriented dipoles increases with the growth of field intensity which is being manifested by the growth in anisotropy of the mechanical properties along the crystallographic directions of the system < 110 >. The kinetics of recovering the properties of the crystals after removing the field has been studied. The activation energy involved in the process of re-orienting the dipoles has been estimated. It turned out to be equal to 0.5 eV