Experimental characterization and physics-based modeling of the temperature-dependent diffuse reflectance of plasma-sprayed Nd2Zr2O7 in the near to short-wave infrared.

Supercontinuum-laser illumination in conjunction with CO2-laser heating has been implemented to measure the near to short-wave infrared (970-1660 nm) diffuse reflectance of plasma-sprayed Nd2Zr2O7 as a function of temperature. Owing to the broadband nature of this experimental technique, the diffuse reflectance of plasma-sprayed Nd2Zr2O7 has been measured at many wavelengths and has been shown to decrease with increasing temperature. A physics-based model for diffuse reflectance predicated on the crystal/electronic band structure of highly scattering semiconductor materials has been constructed to interpret the results of these measurements. Baseline materials characterization has also been performed to assist in the development of crystal/electronic band structure-optical property relationships that could be useful for the design of next-generation environmental barrier coatings. This characterization has included ambient and non-ambient x-ray diffraction as well as room-temperature, integrating-sphere diffuse reflectance spectroscopy.

[1]  Michael E. Thomas,et al.  Temperature-dependent diffuse reflectance spectroscopy of plasma-sprayed Cr-doped α-alumina using supercontinuum laser illumination and CO2 laser heating. , 2017, Applied optics.

[2]  R. M. Springer,et al.  Transmittance derived line width and line shift in polycrystalline Nd:YAG. , 2016, Applied optics.

[3]  S. Gupta,et al.  Role of various defects in the photoluminescence characteristics of nanocrystalline Nd2Zr2O7: an investigation through spectroscopic and DFT calculations , 2016 .

[4]  Shengmin Guo,et al.  Thermal radiation properties of plasma-sprayed Gd2Zr2O7 thermal barrier coatings , 2013 .

[5]  D. Stöver,et al.  Improving Atmospheric Plasma Spraying of Zirconate Thermal Barrier Coatings Based on Particle Diagnostics , 2011, Journal of Thermal Spray Technology.

[6]  D. Clarke,et al.  Neodymium zirconate (Nd2Zr2O7) transparent ceramics as a solid state laser material , 2011 .

[7]  J. C. Chen,et al.  Electronic structure, mechanical properties and thermal conductivity of Ln2Zr2O7 (Ln = La, Pr, Nd, Sm, Eu and Gd) pyrochlore , 2011 .

[8]  Michael E. Thomas,et al.  Optical material characterization through BSDF measurement and analysis , 2010, Optical Engineering + Applications.

[9]  J. Markham,et al.  Determination of Scattering and Absorption Coefficients for Plasma‐Sprayed Yttria‐Stabilized Zirconia Thermal Barrier Coatings at Elevated Temperatures , 2009 .

[10]  K. Idemitsu,et al.  Thermophysical Properties of Rare-Earth-Stabilized Zirconia and Zirconate Pyrochlores as Surrogates for Actinide-Doped Zirconia , 2007 .

[11]  F. Aldinger,et al.  Phase diagrams and thermodynamics of rare-earth-doped zirconia ceramics , 2007 .

[12]  S. Yamanaka,et al.  Photoelectrochemical study of lanthanide zirconium oxides, Ln2Zr2O7 (Ln = La, Ce, Nd and Sm) , 2006 .

[13]  M. F. Reid,et al.  A complete 4fn energy level diagram for all trivalent lanthanide ions , 2005 .

[14]  Peter J. Bonzani,et al.  Improvement to a bench top instrument for measuring spectral emittance at high temperatures , 2003 .

[15]  C. J. Li,et al.  Relationships between the microstructure and properties of thermally sprayed deposits , 2002 .

[16]  Peter R. Solomon,et al.  Bench top Fourier transform infrared based instrument for simultaneously measuring surface spectral emittance and temperature , 1993 .

[17]  R. N. Blumenthal,et al.  Electronic Transport in 8 Mole Percent Y[sub 2]O[sub 3]-ZrO[sub 2] , 1989 .

[18]  R. S. Rana,et al.  A systematic analysis of the spectra of the lanthanides doped into single crystal LaF3 , 1989 .

[19]  R. N. Blumenthal,et al.  High‐Temperature Optical Absorption Measurement of Single‐Crystal, Yttria‐Stabilized Zirconia , 1988 .

[20]  James G. Berryman,et al.  Random close packing of hard spheres and disks , 1983 .

[21]  G. V. Subba Rao,et al.  Oxide pyrochlores — A review , 1983 .

[22]  A. Burggraaf,et al.  Electrical conductivity of fluorite and pyrochlore LnxZr1–xO2–x/2 (Ln = Gd, Nd) Solid Solutions , 1980 .

[23]  R. Chapman,et al.  Some properties of zirconates and stannates with the pyrochlore structure , 1970 .

[24]  É. K. Keler,et al.  COMMUNICATION 3. SOME PRINCIPLES OF THE FORMATION, PHYSICOCHEMICAL AND TECHNICAL PROPERTIES OF ZIRCONATES * , 1966 .