Thermal Barrier Coating on Gamma Titanium Aluminide by EB-PVD: Influence of deposition process parameters on adhesive properties of ceramic top coat

Thermal barrier coating (TBC) systems are indispensable for utilization in gas turbine engines to decrease the thermal effect and enhance turbine efficiency by considerably raising applied gas temperatures. TBCs are typically composed of an underlying metallic bond coat known as MCrAlY (M=Ni,Co) acting as an oxidation resistant layer, and yttria-stabilized zirconia (YSZ) as a ceramic top coat that provides thermal insulation toward the metallic substrate. In this study Inter-metallic alloy based on Gamma Titanium Aluminide was chosen as a substrate due to its low density as compared to the conventional Nickel-based super alloy which made it competent to be an important structural material in high-temperature aerospace and automotive applications. TBC's bond coat and ceramic top coat were performed by EB-PVD at different partial pressures of Oxygen during deposition of the top layer in order to get deeper insight into the correlation between adhesion and deposition process parameters.