Structure and thermal conductivity of Zr1−xGdxO2−x/2 solid solutions

Zr1−xGdxO2−x/2 (x = 0.08, 0.09 and 0.10) solid solutions were synthesized by solid state reaction at 1600 °C for 6 h in air. These compounds consist of cubic (c) and tetragonal (t) phases. The content of cubic phase increases with the increase of gadolinia doping. Phonon scattering is in accordance with the Umklapp processes. Temperature-dependent variation of the thermal conductivity for cubic phase is much less pronounced than that for tetragonal phase. This indicates that the reduction in total thermal conductivity for Zr2−xGdxO2−x/2 at high temperatures should be mainly ascribed to the decrease of thermal conductivity from tetragonal phase.