Multilayer abradable coatings for high-performance systems

Patent metadata

Field	Value
Publication number	US-10858950-B2
Application number	US-201816043755-A
Country	US
Kind code	B2
Filing date	Jul 24, 2018
Priority date	Jul 27, 2017
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

An example high-performance system includes an example high-performance component including a substrate and a multilayer abradable track adjacent to the substrate. The abradable track includes a plurality of alternating layers along a thickness of the abradable track. The plurality of alternating layers includes at least one relatively porous abradable layer and at least one relatively dense layer. A porosity of the relatively dense layer is lower than that of the at least one relatively porous abradable layer. The example high-performance system may include a rotating component configured to contact and abrade the multilayer abradable track. An example technique for forming the multilayer abradable track includes thermal spraying a first precursor composition toward the substrate to form a relatively porous abradable layer of a layer pair of a plurality of layer pairs of the multilayer abradable track, and a second precursor composition to form a relatively dense layer of the pair.

First claim

The invention claimed is:

1. A high-performance component comprising:
a substrate; and
a multilayer abradable track adjacent to the substrate, wherein the multilayer abradable track comprises a plurality of alternating layers along a thickness of the multilayer abradable track, wherein the plurality of alternating layers comprises at least two porous abradable layers and at least two dense layers, the plurality of alternating layers alternating between a first porous layer of the at least two porous layers, a first dense layer of the at least two dense layers, a second porous layer of the at least two porous layers, and a second dense layer of the at least two dense layers, wherein a porosity of the at least two dense layers are lower than a porosity of the at least two porous abradable layers, and wherein the first porous layer is furthest from the substrate of the plurality of alternating layers.

2. The high-performance component of claim 1 , wherein the at least two porous abradable layers exhibit a porosity between 10 vol. % and 40 vol. %.

3. The high-performance component of claim 1 , wherein the at least two dense layers exhibit a porosity less than or equal to 15 vol. %.

4. The high-performance component of claim 1 , wherein the substrate defines a substrate channel comprising the multilayer abradable track.

5. The high-performance component of claim 1 , wherein the substrate defines a major surface, and wherein the multilayer abradable track is disposed on the major surface.

6. The high-performance component of claim 1 , wherein the substrate comprises a ceramic matrix composite.

7. The high-performance component of claim 1 , wherein at least one of the at least two porous abradable layers or the at least two dense layers comprises at least one of aluminum nitride, aluminum diboride, boron carbide, aluminum oxide, mullite, zirconium oxide, carbon, silicon metal, silicon alloy, silicon carbide, silicon nitride, a transition metal nitride, a transition metal boride, a rare earth oxide, a rare earth silicate, a stabilized zirconium oxide, a stabilized hafnium oxide, or barium-strontium-aluminum silicate.

8. The high-performance component of claim 1 , wherein one or both of the at least two porous abradable layers or the at least two dense layers comprise a thermal sprayed composition.

9. The high-performance component of claim 1 , wherein the multilayer abradable track further defines an abradable channel comprising a porous abradable composition.

10. The high-performance component of claim 1 , wherein the high-performance component comprises a substantially cylindrical shroud, and wherein the multilayer abradable track runs along a cylindrical surface defined by the substantially cylindrical shroud.

11. The high-performance component of claim 10 , wherein the multilayer abradable track defines a substantially cylindrical abrasion surface.

12. A high-performance system comprising:
the high-performance component of claim 1 ; and
a rotating component configured to contact an abradable surface defined by the multilayer abradable track with a portion of the rotating component.

13. A method comprising:
forming a multilayer abradable track on a substrate, wherein the multilayer abradable track comprises a plurality of alternating layers along a thickness of the multilayer abradable track, wherein the plurality of alternating layers comprises at least two porous abradable layers and at least two dense layers, the plurality of alternating layers alternating between a first porous layer of the at least two porous layers, a first dense layer of the at least two dense layers, a second porous layer of the at least two porous layers, and a second dense layer of the at least two dense layers,
wherein each porous layer of the at least two porous layers is formed by at least thermal spraying a first precursor composition toward the substrate of a high-performance component to form the porous abradable layer,
wherein each dense layer of the at least two dense layers is formed by at least thermal spraying a second precursor composition toward the substrate to form the dense layer,
wherein a porosity of the at least two dense layers is lower than a porosity of the at least two porous abradable layers,
wherein the first and the second precursor composition comprise a respective matrix composition, and wherein the respective matrix composition comprises at least one of aluminum nitride, aluminum diboride, boron carbide, aluminum oxide, mullite, zirconium oxide, carbon, silicon metal, silicon alloy, silicon carbide, silicon nitride, a transition metal nitride, a transition metal boride, a rare earth oxide, a rare earth silicate, a stabilized zirconium oxide, a stabilized hafnium oxide, or barium-strontium-aluminum silicate, and
wherein the respective matrix composition of the first precursor composition is the same as the respective matrix composition of the second precursor composition.

14. The method of claim 13 , wherein the first precursor composition comprises a porosity-creating additive, and wherein the porosity-creating additive comprises one or more of graphite, hexagonal boron nitride, a polymer, a polyester.

15. The method of claim 14 , wherein the concentration of the porosity-creating additive in the first precursor composition is controlled to cause the at least two porous abradable layers to exhibit a porosity between 10 vol. % and 40 vol. %.

16. The method of claim 13 , wherein the second precursor composition comprises the porosity-creating additive, wherein the concentration of the porosity-creating additive in the second precursor composition is controlled to cause the at least two dense layers to exhibit a porosity less than or equal to 15 vol. %.

17. The method of claim 13 , further comprising at least one of fabricating the substrate to define a substrate channel or fabricating the multilayer abradable track to define an abradable channel.

Assignees

• Rolls Royce Corp
• Rolls Royce Nam Tech Inc
• Rolls Royce North America Tech Inc

Inventors

• Shi Jun
• Li Li
• Freeman Ted J

Classifications

• F01D11/14

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• F01D5/284

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• F01D11/12

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• F05D2300/514

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