Thermal barrier coating bonded by (Al2O3–Y2O3)/(Y2O3-stabilized ZrO2) laminated composite coating prepared by two-step cyclic spray pyrolysis

• DOI: 10.1016/j.corsci.2013.10.006
• Publication Date: 2013-10-10T14:36:28Z
• Authors: Junqi Yao; Yedong He; Deren Wang; Hui Peng; Hongbo Guo; Shengkai Gong
• Keywords: 02 engineering and technology; 0210 nano-technology

Abstract Thermal barrier coating bonded by (Al2O3–Y2O3)/(Y2O3-stabilized ZrO2) (YSZ) laminated coating has been developed on Ni-based superalloy by two-step cyclic pyrolysis. It is demonstrated, from cyclic oxidation tests at 1100 °C, that YSZ top coat and alloy substrate can be bonded together effectively by the (Al2O3–Y2O3)/YSZ laminated coating, showing good resistance to oxidation, cracking, spallation and buckling. These beneficial effects can be attributed to the sealing effect of the designed multi-sealed compact bond coat with α-Al2O3 layers, the decrease of thermal stresses, the increase of fracture toughness in such bond coat and no interdiffusion between the substrate and bond coat.