Thermal radiation properties of plasma-sprayed Gd2Zr2O7 thermal barrier coatings

The reflectance and transmittance spectra of plasma-sprayed Gd2Zr2O7 coatings were measured and the absorption and scattering coefficient as a function of wavelength were extracted using the four-flux model. Results showed that Gd2Zr2O7 is a high scattering, low absorption material at the wavelength <6 mu m, and the scattering coefficient decreases with the increase of wavelength. Compared with yttria-stabilized zirconia, Gd2Zr2O7 shows higher reflectance and lower transmittance in the wavelength range of 0.8-2.7 mu m, which is desirable in thermal barrier coating applications. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.