THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS III IIIIJII Hot Corrosion Resistance of Thermal Barrier Coatings

ABSTRACT The hot corrosion resistance of yttria stabilized zirconia (YSZ) thermal barrier coatings was evaluated using an atmospheric burner rig. The coatings were deposited by plasma spraying and electron beam physical vapor deposition (EB-PVD). The tests were performed for up to 2000 hours at I700°F and 1300°F. The test parameters were designed to simulate the deposit chemistry and corrosion microstructures observed in marine gas turbine engines. The YSZ coating performed very well in the tests, with no spallation and little bond coat corrosion. Plasma sprayed YSZ coating was also evaluated by engine testing in a hot corrosive environment. Post test evaluation showed virtually no corrosion of the ceramic or the bond coat. Parts that were not ceramic coated had undergone severe corrosion. The results are discussed in terms of coating microstructures and the chemistry of the environment