Experimental and Modeling Studies of Thermal Barrier Coating Failure Under Isothermal Oxidation and Solid Particle Erosion

The hot section components of aerospace gas turbines are facing a material problem with continuously increasing the working temperature (up to 1700°C) of the turbine engines in order to achieve improved efficiency. Commonly used nickel-based superalloys for these components exhibit deficiency in such a high temperature condition, therefore thermal barrier coatings (TBCs) have been developed, which can be applied on the nickel-based superalloy substrate via various deposition techniques, to reduce the temperature exerted on the substrate material. In this research, the failure behavior of a TBC system that consists of an 8 wt% yttria partially stabilized zirconia (YSZ) top coat and CoNiCrAlY (Praxair CO 211) bond coat, deposited on nickel based superalloy Inconel 718 substrate via atmospheric plasma spraying (APS) process, has been studied experimentally under isothermal oxidation loading and solid particulate erosion to have a better understanding of the failure mechanisms of the TBC system.