Comparison of Oxidation and Thermal Shock Performance of Thermal Barrier Coatings

Operating temperatures in gas turbine engines have reached to 1200 degrees C with the latest developments in coating technology. Thermal shock and furnace oxidation tests are widely used to determine thermal barrier coating (TBC) performance and its durability in aircraft applications. This paper presents the results of thermal shock and furnace oxidation tests, carried out with regard to the microstructure and TGO (thermally grown oxide) growth behavior of TBC systems. Isothermal oxidation behavior of TBCs was evaluated through examination of microstructure, formation, and growth behavior of TGO layers at 1200 degrees C for different time periods in furnace oxidation tests. On the other hand, thermal shock behavior of TBC was evaluated through examination of its durability at 1200 degrees C with thermal shock test, which was carried out until the coating failure became visible. The relationship between the TGO growth and oxidation behavior was discussed using furnace oxidation test results.