Thermal Conductivity of Calcium Aluminate and Complex Vanadates of Garnet Structure

Abstract

The thermal conductivity of materials with the nonstoichiometric garnet structure, namely, of calcium aluminate Са12Al14O33±δ (both single crystal and ceramic) and doped vanadates Ca5Mg4–xMx(VO4)6 (M = Zn, Co; 0 ≤ x ≤ 4), in the temperature interval 50–300 K was studied by the steady state comparative-longitudinal thermal flux method. The compositions Ca5Mg4–xZnx(VO4)6, x =1, 3, 4, were studied in the temperature interval 298–573 K by the dynamic method. The effect of the defective structure on the thermal conductivity of the materials was discussed. The thermal conductivity of the materials is ~2 W m–1 K–1 at room temperature and above.