Temperature Mapping at the Thermal Barrier Coating/Bond Coat Interface by Luminescence Lifetime Imaging Using Integrated Erbium-Doped Sublayers

Eldridge, Jeffrey I ; Wroblewski, Adam C ; Wolfe, Douglas E

关键词: COATINGS;    CRACK PROPAGATION;    DELAMINATING;    DETECTION;    EROSION;    FILM COOLING;    HEAT FLUX;    IMAGING TECHNIQUES;    INFRARED RADIATION;    LASERS;    LUMINESCENCE;    TEMPERATURE GRADIENTS;    TEMPERATURE MEASUREMENT;    THERMOGRAPHY;    THERMAL MAPPING;   

RP-ID  :  GRC-E-DAA-TN64850

学科分类：物理（综合）

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

Full-field temperature mapping of thermal barrier coated components by either infrared thermography or phosphor thermometry has been limited to surface temperature mapping even though temperature mapping at the thermal barrier coating (TBC)/bond coat interface is more relevant for evaluating the TBC thermal protection performance. For the first time, 2D temperature mapping at the TBC/bond coat interface has now been achieved by full-field luminescence lifetime imaging measurements of emission from a thin erbium-doped yttria-stabilized zirconia (YSZ) sensing layer integrated into the TBC below the overlying undoped YSZ. This new capability was applied to map temperatures at the TBC/bond coat interface for TBC-coated specimens subjected to a heat flux produced by the NASA Glenn high heat flux laser facility. In particular, thermal gradients at the TBC/bond coat interface were mapped in regions where the TBC was subjected to erosion or to mechanically induced delamination crack propagation. Finally, temperature mapping of the TBC/bond coat interface was used to evaluate the effectiveness of surface air film cooling at the TBC/bond coat interface.