Method for forming a temperature sensing layer within a thermal barrier coating
A thermal barrier coated component, such as a turbine blade formed from a superalloy substrate, includes a thermal barrier coating applied onto the substrate. A metallic bond coat layer is on the substrate and includes rare-earth luminescent dopants. A ceramic top coat layer is on the bond coat layer. A temperature sensing thermally grown oxide (TGO) layer is formed at the interface of the bond coat layer and ceramic top coat layer. The temperature sensing TGO layer includes grown rare-earth luminescent ions migrated from the metallic bond coat layer in an amount sufficient to enable luminescence sensing of the TGO layer for real-time phosphor thermometry temperature measurements at the TGO layer.
1. A method of forming a thermal barrier coated component, comprising:
applying a metallic bond coat layer onto a substrate, said metallic bond coat layer including about 96 to 98 percent of NiCoCrAlY and about 2.0 to about 4.0 percent of rare-earth luminescent dopants selected from the group consisting of samarium, erbium, europium, dysprosium, praseodymium, and terbium;
applying a ceramic top coat layer on the bond coat layer; and
forming a heat aged, high temperature sensing thermally grown oxide (TGO) layer at the interface of the bond coat layer and ceramic top coat layer by heat ageing the metallic bond coat layer and ceramic top coat layer to migrate rare-earth luminescent ions selected from the group consisting of samarium, erbium, europium, dysprosium, praseodymium, and terbium from the metallic bond coat layer into the interface of the bond coat layer and the ceramic top coat layer in an amount sufficient to enable high temperature luminescence sensing up to about 1,100° C. of the TGO layer for real-time phosphor thermometry temperature measurements at the TGO layer, wherein said TGO layer comprises about 1.7 to 2.0 weight percent of nickel, about 0.67 to 0.82 weight percent of chromium, about 52.7 to 64.4 weight percent of aluminum, about 35.0 to about 42.7 weight percent of oxygen, and no more than about 0.1 weight percent of the rare-earth dopants selected from the group consisting of samarium, erbium, europium, dysprosium, praseodymium, and terbium.
2. The method of claim 1 , wherein said ceramic top coat layer comprises a ytrria-stabilized zirconia (YSZ) barrier top coat layer on the bond coat layer.
3. The method of claim 1 , wherein said substrate comprises a turbine component or an engine exhaust component.
4. The method of claim 1 , wherein said bond coat layer is about 50 to 200 micrometers and said ceramic top coat layer is about 50 to 300 micrometers.
5. The method of claim 1 , wherein the substrate comprises a superalloy substrate.