US-12624225-B2 - Environmental barrier coating

Abstract

An article according to an exemplary embodiment of this disclosure, among other possible things includes a substrate and a barrier layer on the substrate. The barrier layer includes a bond coat comprising a matrix, diffusive particles disposed in the matrix, and gettering particles disposed in the matrix; a topcoat; and a porous interlayer disposed between the topcoat and the bond coat. The porous interlayer has a porosity that is greater than a porosity of the topcoat. A slurry composition for applying an interlayer to an article and method of applying a top coat to an article are also disclosed.

Inventors

• Xia Tang
• Richard Wesley Jackson, III
• James T. Beals
• David A. Litton
• Brian T. Hazel

Assignees

• RTX CORPORATION

Dates

Publication Date

20260512

Application Date

20220624

Claims (16)

1. 1 . An article, comprising: a substrate; and a barrier layer on the substrate, the barrier layer including: a bond coat comprising a matrix, diffusive particles disposed in the matrix, and gettering particles disposed in the matrix, a topcoat, and a porous interlayer disposed between the topcoat and the bond coat, the porous interlayer having a porosity that is greater than a porosity of the topcoat: wherein the topcoat and the porous interlayer include at least one of hafnia, hafnium silicate, yttrium monosilicate, yttrium disilicate, ytterbium monosilicate, ytterbium disilicate, yttria stabilized zirconia, gadolinia stabilized zirconia, calcium aluminosilicates, mullite, and barium strontium aluminosilicate.
2. 2 . The article of claim 1 , wherein the porous interlayer and the topcoat include a common material.
3. 3 . The article of claim 2 , wherein the common material includes at least one of hafnia, hafnium silicate, yttrium monosilicate, yttrium disilicate, ytterbium monosilicate, ytterbium disilicate, yttria stabilized zirconia, gadolinia stabilized zirconia, calcium aluminosilicates, mullite, and barium strontium aluminosilicate.
4. 4 . The article of claim 2 , wherein the common material includes at least one of hafnia and hafnium silicate.
5. 5 . The article of claim 2 , wherein the common material includes at least one of yttrium monosilicate and yttrium disilicate.
6. 6 . The article of claim 2 , wherein the common material includes at least one of ytterbium monosilicate and ytterbium disilicate.
7. 7 . The article of claim 2 , wherein the common material includes at least one of yttria stabilized zirconia and gadolinia stabilized zirconia.
8. 8 . The article of claim 2 , wherein the common material includes at least one of calcium aluminosilicates and mullite.
9. 9 . The article of claim 1 , wherein a ratio of a thickness of the porous interlayer to a thickness of the top coat is between about 0.5 to about 1.
10. 10 . The article of claim 1 , wherein a ratio of a thickness of the porous interlayer to a thickness of the bond coat is between about 0.1 and 0.5.
11. 11 . The article of claim 1 , wherein a porosity of the porous interlayer is between about 5 and 50 percent.
12. 12 . The article of claim 11 , wherein a porosity of the porous interlayer is about 25 percent.
13. 13 . The article of claim 11 , wherein a porosity of the top coat is less than about 10 percent.
14. 14 . The article of claim 1 , wherein the porous interlayer includes pores, and wherein a porosity of the interlayer is between about 5% and about 25%.
15. 15 . The article of claim 1 , wherein the porous interlayer includes silica.
16. 16 . The article of claim 15 , wherein the porous interlayer includes more silica than the topcoat.

Description

BACKGROUND A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. Air entering the compressor section is compressed and delivered into the combustion section where it is mixed with fuel and ignited to generate a high-energy exhaust gas flow. The high-energy exhaust gas flow expands through the turbine section to drive the compressor and the fan section. The compressor section typically includes low and high pressure compressors, and the turbine section includes low and high pressure turbines. This disclosure relates to composite articles, such as those used in gas turbine engines, and methods of coating such articles. Components, such as gas turbine engine components, may be subjected to high temperatures, corrosive and oxidative conditions, and elevated stress levels. In order to improve the thermal and/or oxidative stability, the component may include a protective barrier coating. SUMMARY An article according to an exemplary embodiment of this disclosure, among other possible things includes a substrate and a barrier layer on the substrate. The barrier layer includes a bond coat comprising a matrix, diffusive particles disposed in the matrix, and gettering particles disposed in the matrix; a topcoat; and a porous interlayer disposed between the topcoat and the bond coat. The porous interlayer has a porosity that is greater than a porosity of the topcoat. In a further example of the foregoing, the porous interlayer and the topcoat include a common material. In a further example of any of the foregoing, the common material includes at least one of hafnia, hafnium silicate, yttrium mono silicate, yttrium disilicate, ytterbium monosilicate, ytterbium disilicate, yttria stabilized zirconia, gadolinia stabilized zirconia, calcium aluminosilicates, mullite, and barium strontium aluminosilicate, or combinations thereof. In a further example of any of the foregoing, the topcoat and the porous interlayer include at least one of hafnia, hafnium silicate, yttrium monosilicate, yttrium disilicate, ytterbium monosilicate, ytterbium disilicate, yttria stabilized zirconia, gadolinia stabilized zirconia, calcium aluminosilicates, mullite, and barium strontium aluminosilicate, or combinations thereof. In a further example of any of the foregoing, a ratio of a thickness of the porous interlayer to a thickness of the top coat is between about 0.5 to about 1. In a further example of any of the foregoing, a ratio of a thickness of the porous interlayer to a thickness of the bond coat is between about 0.1 and 0.5. In a further example of any of the foregoing, a porosity of the porous interlayer is between about 5 and 50 percent. In a further example of any of the foregoing, a porosity of the porous interlayer is about 25 percent. In a further example of any of the foregoing, a porosity of the top coat is less than about 10 percent. In a further example of any of the foregoing, the porous interlayer includes pores, and a porosity of the interlayer is between about 5% and about 25%. In a further example of any of the foregoing, the porous interlayer includes silica. In a further example of any of the foregoing, the porous interlayer includes more silica than the topcoat. A slurry composition for applying an interlayer to an article according to an exemplary embodiment of this disclosure, among other possible things includes a carrier fluid, particles of an interlayer material, the particles having a multimodal size distribution wherein at least 50 percent of the particles have a diameter between about 0.5 and about 3 microns (0.02 to 0.1 mils), at least one sintering aid or precursor sintering aid, and at least one dispersant/binder. In a further example of any of the foregoing, all or substantially all of the particles have a diameter less than about 15 microns (0.6 mils) and greater than about 0.1 microns (0.004 mils). In a further example of any of the foregoing, the particles include particles of at least one of hafnia, hafnium silicate, yttrium monosilicate, yttrium disilicate, ytterbium monosilicate, ytterbium disilicate, yttria stabilized zirconia, gadolinia stabilized zirconia, calcium aluminosilicates, mullite, and barium strontium aluminosilicate, or combinations thereof. A method of applying a top coat to an article according to an exemplary embodiment of this disclosure, among other possible things includes providing an article having a bond coat, applying a slurry directly onto the bond coat, the slurry including particles of an interlayer material and at least one sintering aid or sintering aid precursor in a carrier fluid, and sintering the interlayer. In a further example of the foregoing, the sintering aid includes at least one of silica, alkaline earth aluminosilicates, rare earth aluminosilicates, borosilicates, or combinations thereof. In a further example of any of the foregoing, the slurry includes silica precursor. The silica precursor transfo