US Patent 7927714 Barium-doped bond coat for thermal barrier coatings

A metallic article for high temperature applications such as a turbine engine component is protected by a thermal barrier coating system on the article's metallic substrate. The thermal barrier coating system includes a bond coat layer of aluminum containing alloy on the metal substrate, an alumina layer on the bond coat layer and a ceramic thermal barrier layer on the alumina layer. The bond coat layer is doped with elemental barium that enhances the creep resistance of the alumina layer, thus, minimizing spallation of the ceramic thermal barrier layer.