Article for high temperature service

Patent metadata

Field	Value
Publication number	US-12196108-B2
Application number	US-202217994459-A
Country	US
Kind code	B2
Filing date	Nov 28, 2022
Priority date	Aug 25, 2014
Publication date	Jan 14, 2025
Grant date	Jan 14, 2025

Abstract

An article for high temperature service is presented herein. One embodiment is an article including a substrate having a silicon-bearing ceramic matrix composite; and a layer disposed over the substrate, wherein the layer includes silicon and a dopant, the dopant including aluminum. In another embodiment, the article includes a ceramic matrix composite substrate, wherein the composite includes a silicon-bearing ceramic and a dopant, the dopant including aluminum; a bond coat disposed over the substrate, where the bond coat includes elemental silicon, a silicon alloy, a silicide, or combinations including any of the aforementioned; and a coating disposed over the bond coat, the coating including a silicate (such as an aluminosilicate or rare earth silicate), yttria-stabilized zirconia, or a combination including any of the aforementioned.

First claim

What is claimed:

1. An article comprising:
a substrate comprising a silicon-bearing ceramic matrix composite, wherein the silicon-bearing ceramic matrix composite comprises a dopant, wherein the dopant comprises aluminum, wherein the aluminum is present in the silicon-bearing ceramic matrix composite at a concentration such that a ratio of aluminum atoms to a sum of aluminum atoms plus silicon atoms [Al/(Al+Si)] is in a range from 0.06 to 0.15;
a bond coat disposed over the silicon-bearing ceramic matrix composite; and
a top coat disposed over the bond coat.

2. The article of claim 1 , wherein the dopant comprises a material selected from the group consisting of aluminum, aluminum oxide, aluminum carbide, aluminum nitride, aluminum boride, and combinations thereof.

3. The article of claim 1 , wherein the aluminum is present in a doped region of the silicon-bearing ceramic matrix composite.

4. The article of claim 3 , wherein the doped region of the silicon-bearing ceramic matrix composite extends at least 25 μm beneath a surface of the silicon-bearing ceramic matrix composite.

5. The article of claim 1 , wherein the dopant is distributed substantially uniformly within the silicon-bearing ceramic matrix composite.

6. The article of claim 1 , wherein the silicon-bearing ceramic matrix composite comprises silicon carbide, silicon nitride, or a combination thereof.

7. The article of claim 1 , wherein the bond coat comprises elemental silicon, a silicon alloy, a silicide, or a combination thereof.

8. The article of claim 1 , wherein the bond coat comprises elemental silicon.

9. The article of claim 1 , wherein the bond coat further comprises a bond coat dopant.

10. The article of claim 9 , wherein the bond coat dopant comprises aluminum, aluminum oxide, aluminum carbide, aluminum nitride, aluminum boride, and combinations including any of the aforementioned.

11. The article of claim 9 , wherein the bond coat dopant comprises aluminum oxide at a concentration such that a ratio of aluminum atoms to a sum of aluminum atoms plus silicon atoms [Al/(Al+Si)] in the bond coat is in a range from 0.01 to 0.15.

12. The article of claim 1 , further comprising:
an over-coat on the bond coat and between the bond coat and the top coat, wherein the over-coat comprises silica.

13. The article of claim 12 , wherein the top coat comprises a silicate.

14. The article of claim 13 , wherein the silicate comprises an aluminosilicate or a rare earth silicate.

15. The article of claim 12 , wherein the top coat comprises an yttria-stabilized zirconia.

16. The article of claim 1 , wherein the aluminum incorporates in a silica film forming on the silicon-bearing ceramic matrix composite upon exposure to a high temperature, oxidative environment.

17. The article of claim 1 , wherein the article comprises a gas turbine combustion liner, a gas turbine transition piece, a gas turbine shroud, a gas turbine vane, or gas turbine blade.

Assignees

• Gen Electric

Inventors

• Luthra Krishan Lal
• Wan Julin
• Sarrafi-Nour Reza

Classifications

• F05D2300/6033

  Ceramic matrix composites [CMC] · CPC title

• C04B41/85

  with inorganic materials · CPC title

• C04B41/5035

  Silica · CPC title

• Y10T428/12056

  Entirely inorganic · CPC title

• F05D2240/35

  Combustors or associated equipment · CPC title