Author(s): , , , , ,

Keywords: , , , , , , , , , , , , , , , , , , ,

Abstract: Using the transient plane source (TPS) technique, the authors investigated the thermal properties of a series of yttria-stabilized zirconia (YSZ) thermal barrier coatings (TBCs). The YSZ coatings had varying amounts of impurities (Zr, Y, Si, Al oxides) and the amount of impurity affected the post-spray properties of the coating. TBCs are exposed to high temperatures during their regular operation, which can lead to the degeneration of the coating if the impurity content is high enough. The thermal conductivity of the sprays were measured before exposure to heat and then after exposure to high temperatures ( > 1000°C). After exposure to heat, the thermal conductivity of all the coatings increased by roughly 50%, which is undesirable because TBCs protect components of a machine that aren't supposed to be exposed to heat. A higher impurity content led to a higher thermal conductivity value after exposure to heat.

Reference: Journal of Thermal Spray Technology, 16, 5-6 (2007) 804-808

DOI: 10.1007/s11666-007-9079-7