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Development of YAG:Dy Thermographic Phosphor Coatings for Turbine Engine ApplicationsThe selection and development of thermographic phosphor coatings were pursued to meet the objective of demonstrating luminescence-decay-based temperature measurements up to 1300C on the surface of a vane in an operating demonstrator turbine engine. To meet this objective, YAG:Dy was selected based on the desirable luminescence performance observed for YAG:Dy powder: (1) excellent temperature sensitivity and intensity at operating turbine engine temperatures, (2) an emission peak at the relatively short wavelength of 456 nm, where the interference from background blackbody radiation is fairly low, and (3) its nearly single exponential decay which makes for a simple, reliable temperature calibration. However, implementation of YAG:Dy for surface temperature measurements required application of YAG:Dy as a coating onto the surface of a superalloy component with a preexisting yttria-stabilized zirconia (YSZ) thermal barrier coating (TBC). An inherent dilemma in producing a YAG:Dy coating is that coating processing is constrained to be performed at temperatures below (less than 1200C) what is considered safe for the superalloy component, much lower than temperatures used to produce the high quality crystalline powder. Therefore, YAG:Dy coatings tend to exhibit lower luminescence performance compared to well prepared YAG:Dy powder, and the luminescence performance of the coating will depend on the method of coating deposition. In this presentation, the luminescence performance of YAG:Dy coatings prepared by the different methods of (1) application of a binder-based YAG:Dy-containing paint, (2) solution precursor plasma spray (SPPS), and (3) electron-beam physical vapor deposition (EB-PVD) and the effect of post-deposition heat treatments will be discussed.
Document ID
Document Type
Eldridge, J. I.
(NASA Glenn Research Center Cleveland, OH, United States)
Jenkins, T. P.
(MetroLaser, Inc. Irvine, CA, United States)
Allison, S. W.
(Oak Ridge National Lab. TN, United States)
Wolfe, D. E.
(Pennsylvania State Univ. University Park, PA, United States)
Jordan, E. H.
(Connecticut Univ. Storrs, CT, United States)
Date Acquired
August 26, 2013
Publication Date
June 5, 2012
Subject Category
Nonmetallic Materials
Report/Patent Number
Meeting Information
58th International Instrumentation Symposium
Funding Number(s)
WBS: WBS 031102.02.03.0890.12
Distribution Limits
Public Use Permitted.
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