Real structure and thermal properties of solid solutions of γ-GdxDy1−xS1.5−y.

The work is devoted to the study of temperature dependences of thermal conductivity (T = 300–770 K) of polycrystallic samples of solid solutions based on gadolinium and dysprosium sulfides of the compositions: γ-Gd_xDy_1−xS_1.49 (x = 0.1, 0.2, 0.3, 0.4). It has been found that the morphological features of samples, namely, the specific surface area of crystallites, which causes a change in the number of deformation centers, determines the value of the thermal conductivity of γ-Gd_xDy_1−xS_1.49 solid solutions. The presence of an abnormal decrease in thermal conductivity for the composition of x = 0.2 has been established. When the temperature increases to 770 K, this anomaly decreases slightly. The minimum value of the thermal conductivity coefficient of 0.68 ± 0.03 W/(m·K) is reached for the composition under consideration at 770 K. [ABSTRACT FROM AUTHOR]