Wan, ChunleiSparks, Taylor DavidWei, PanClarke, David2013-09-192010Wan, Chunlei, Taylor D. Sparks, Pan Wei, David R. Clarke. 2010. Thermal conductivity of the rare-earth strontium aluminates. Journal of the American Ceramic Society 93(5): 1457-1460.0002-7820http://nrs.harvard.edu/urn-3:HUL.InstRepos:11077825The thermal conductivity of a series of complex aluminates, RE2SrAl2O7, with different rare-earth (RE) ions, has been measured up to 1000°C. There is a strong dependence on the atomic number of the RE ion, ranging from an approximately 1/T dependence for the lanthanum strontium aluminate to an almost temperature-independent behavior of the dysprosium strontium aluminate. The latter conductivity is comparable with that of yttria-stabilized zirconia, the current material of choice for thermal barrier coatings. The temperature dependence of the thermal conductivities of all the aluminates studied can be fit to a standard phonon–phonon scattering model, modified to account for a minimum phonon mean free path, in which the difference in behavior is attributed to increased phonon–phonon scattering with the atomic mass of the RE ion. Although a satisfactory parametric fit is obtained, the model does not take into account either the detailed layer structure of the aluminates, consisting of alternating rock-salt and perovskite layers in a natural superlattice structure, or the site preferences of the RE ion. This suggests that further model development is warranted.en-USJournal Article10.1111/j.1551-2916.2009.03594.x