Thermal barrier coating compositions, methods of manufacture thereof and articles comprising the same

Patent metadata

Field	Value
Publication number	US-10968756-B2
Application number	US-201715449673-A
Country	US
Kind code	B2
Filing date	Mar 3, 2017
Priority date	Mar 3, 2017
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

A process for coating a gas turbine engine component is disclosed herein. The process comprises applying a bond coat on a substrate of a gas turbine engine. A thermal barrier material is applied to the bond coat. A coating containing polynuclear aluminum oxide/hydroxide clusters is then applied to the thermal barrier material. The polynuclear aluminum oxide/hydroxide clusters are Al13 Keggin clusters having the formula [AlO4Al12(OH)24(H2O)12]7+, or are salts of the Al13 Keggin clusters called Al13 Keggin complexes. A gas turbine engine component comprising a superalloy substrate; a bond coat disposed on the substrate; a thermal barrier material on the bond coat; and a coating containing the polynuclear aluminum oxide/hydroxide clusters on the thermal barrier material is disclosed herein.

First claim

What is claimed is:

1. A process for coating a component, comprising:
applying a bond coat on a substrate of a component;
applying a thermal barrier material to the bond coat; and
applying a coating containing polynuclear aluminum oxide/hydroxide clusters, to the thermal barrier material; wherein the polynuclear aluminum oxide/hydroxide clusters are Al 13 Keggin clusters having the formula [AlO 4 Al 12 (OH) 24 (H 2 O) 12 ] 7+ , or are Al 13 Keggin complexes of salts of the Al 13 Keggin clusters, wherein the Al 13 Keggin complex has the formula {[AlO 4 Al 12 (OH) 24 (H 2 O) 12 ] 7+ *7NO 3 − }.

2. The process of claim 1 , wherein the Al 13 Keggin complex has the formula {[AlO 4 Al 12 (OH) 24 (H 2 O) 12 ] 7+ *7NO 3 − }.

3. The process of claim 1 , further comprising obtaining the Al 13 Keggin clusters or the Al 13 Keggin complexes by base neutralization of an aluminum salt solution, where the salt solution comprises a total aluminum concentration of about 0.02 to about 2.0 moles/liter, to obtain an (OH − /Al) mole ratio of about 2.1 to about 2.6.

4. The process of claim 1 , further comprising obtaining the Al 13 Keggin clusters or the Al 13 Keggin complexes by base neutralization of an aluminum salt solution, where the salt solution comprises a total aluminum concentration of about 0.02 to about 2.0 moles/liter, to obtain an (OH − /Al) mole ratio of about 2.2 to about 2.4.

5. The process of claim 1 , further comprising preparing the coating from a solution that comprises the Al 13 Keggin clusters or the Al 13 Keggin complexes in an amount of about 0.007 to about 0.07 moles/liter of the solution; where the solution comprises water or an organic solvent.

6. The process of claim 5 , further comprising precipitating the Al 13 Keggin clusters or the Al 13 Keggin complexes from a solution and collecting the Al 13 Keggin clusters or the Al 13 Keggin complexes by filtration, and drying the solution to form Al 13 Keggin cluster and/or Al 13 Keggin complex powder.

7. The process of claim 6 , further comprising dissolving the Al 13 Keggin cluster or Al 13 Keggin complex powder in water with a polymeric binder to form the coating.

8. The process of claim 1 , wherein the coating is applied by painting, spraying, electrostatic spraying, or spin-coating.

9. The process of claim 1 , further comprising drying the Al 13 Keggin clusters to form a pre-condensed coating of hydrated pseudo-boehmite (AlOOH*H 2 O), aluminum trihydroxide, or a combination thereof.

10. The process of claim 1 , further comprising heat treating the coating to form a fully dense transition alumina coating selected from the group consisting of χ-Al 2 O 3 , η-Al 2 O 3 and γ-Al 2 O 3 that has a thickness of about 1 to about 1000 nanometers.

11. The process of claim 1 , further comprising coagulating the Al 13 Keggin clusters or the Al 13 Keggin complexes with an aqueous solution of sodium silicate, where the sodium silicate is present in an amount of about 0.01 to about 0.1 moles/liter to form a hydroxy aluminosilicate compound, where the sodium silicates comprise sodium meta-silicate, sodium orthosilicate, disodium disilicate, or a combination thereof.

12. The process of claim 11 , wherein an Al/Si atomic ratio ranges from about 5:1 to 15:1.

13. The process of claim 11 , wherein the coating comprises the Al 13 Keggin cluster and the hydroxy aluminosilicate compound and wherein the coating is applied by dipping, painting, spraying, electrostatic spraying, spin-coating, or a combination thereof.

Assignees

• United Technologies Corp
• Raytheon Tech Corp

Inventors

• Opalka Susanne M
• Li Weina

Classifications

• C23C4/02 Primary

  Pretreatment of the material to be coated, e.g. for coating on selected surface areas · CPC title

• B05B5/00

  Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means · CPC title

• B05B7/22

  electrically {, magnetically or electromagnetically}, e.g. by arc {(B05B7/20 takes precedence)} · CPC title

• B05B7/20

  by flame or combustion · CPC title

• C23C28/3215

  at least one MCrAlX layer · CPC title