Corrosion study of Alumina/Yttria-Stabilized Zirconia (Al2O3/YSZ) nanostructured Thermal Barrier Coatings (TBC) exposed to high temperature treatment

Thermal Barrier Coatings (TBC) of 8% Yttria-Stabilized Zirconia (8YSZ) were deposited on AISI-304 substrates via r.f magnetron sputtering. A buffer layer of alumina, Al2O3, was deposited to improve the adhesion of the YSZ monolayer to the substrate. The influence of the Al2O3/8YSZ coating on the electrochemical conductance evolution, CtT, was examined by Electrochemical Impedance Spectroscopy measurements when the steels are exposed to temperatures of 700 and 500 °C for 2, 4, and 6 h. Results indicated that CtT diminished three orders of magnitude, in samples coated with Al2O3/8YSZ with respect to uncoated steel.