Local order and thermal conductivity in yttria-stabilized zirconia. II. Numerical and experimental investigations of thermal conductivity

The thermal conductivity of yttria-stabilized zirconias has been determined numerically, by applying a nonequilibrium molecular dynamic calculation. Comparing random configurations and Monte Carlo configurations in which chemical correlations are taken into account, we have established that the short range order developing in yttria-stabilized zirconia gives rise to an increase in lattice thermal conductivity for high dopant concentrations and temperatures below 800 K. At higher temperatures or for lower concentrations, the short range order does not influence the thermal conductivity. This conclusion is consistent with experiment. The results are discussed in relation with the various phonon scattering mechanisms.