Thermal conductivity of (U,Ce)O2 with and without Nd or Zr

The thermal conductivities of (U0.8-xCe0.2Mx)O2 [M: Nd (0≤x≤0.13) or Zr (0≤x≤0.06)] were evaluated from the thermal diffusivity measured by the laser flash method. The thermal conductivities of (U0.8-Ce0.2Mx)O2 indicated a systematic decrease with increasing M-atom content at all temperatures from 200 to 1500 K. In addition, the thermal conductivities of all samples decreased with increasing temperature up to about 1000 K. Up to about 1000 K, the thermal conductivity of (U0.8-xCe0.2Mx)O2 could be expressed as a function of M-element content by the phonon conduction equation