Thermal expansion and thermal conductivity of Cs 2CrO 4

Abstract

The temperature dependence of the lattice parameters of Cs 2CrO 4 was measured by the high-temperature X-ray diffraction method from 293–873 K. The linear thermal expansion of Cs 2CrO 4 obtained from the temperature dependence of the lattice parameters was 2.34% at 873 K, which was about four times that of UO 2 and more than twice that of the stainless steel (SS316). The thermal diffusivity of Cs 2CrO 4 was measured by the laser flash method from 296–1040 K. The thermal conductivity of Cs 2CrO 4 was evaluated from the measured thermal diffusivity and bulk density, and the specific heat capacity from the literature. The thermal conductivity of Cs 2CrO 4 corrected for 100% TD remained almost constant up to 500 K, increased with temperature above 500 K, and it was 0.40 W m −1 K −1 at 800 K, which was less than 10 and 12% of those of UO 2 and U 0.8Pu 0.2O 1.98, respectively.