Patent ID: 8337996

Claim:
A vanadium resistant coating system resistant to high temperature vanadium attack, comprising: a superalloy substrate; a bond coat resistant to attack by corrosive by-products resulting from the combustion of fuels, the bond coat comprising a first layer of MCrAlY overlying the superalloy substrate, where M is a metal selected from the group consisting of Ni, Cr and Fe and combinations thereof, and a second layer overlying the first layer, the second layer comprising a precious metal; a ceramic coating overlying the bond coat, the ceramic coating further comprising a zirconium oxide stabilized by a cation of a rare earth element species having a smaller atomic radii than Y 3+ , wherein the cation forms an oxide of the species; and wherein the cation has a lower enthalpy of formation with V 2 O 5 than Y 3+ ; and a sacrificial ceramic oxide layer overlying the ceramic coating, the sacrificial ceramic oxide layer further comprising a zirconium oxide stabilized by yttria and a zirconium oxide stabilized by a cation of a rare earth species having a larger atomic radius than Y 3+ , and wherein the cation forms an oxide of the species and can be attacked by V 2 O 5 before the zirconium oxide stabilized by yttria.