Plasma spray physical vapor deposition deposited in multilayer, multi-microstructure environmental barrier coating

Patent metadata

Field	Value
Publication number	US-12006567-B2
Application number	US-202117167662-A
Country	US
Kind code	B2
Filing date	Feb 4, 2021
Priority date	Jan 29, 2016
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

An article may include a substrate defining at least one at least partially obstructed surface. The substrate includes at least one of a ceramic or a ceramic matrix composite. The article also may include a multilayer, multi-microstructure environmental barrier coating on the at least partially obstructed substrate. The multilayer, multi-microstructure environmental barrier coating includes a first layer comprising a rare earth disilicate and a substantially dense microstructure; and a second layer on the first layer. The second layer includes a columnar microstructure and at least one of a rare earth monosilicate or a thermal barrier coating composition comprising a base oxide comprising zirconia or hafnia; a primary dopant comprising ytterbia; a first co-dopant comprising samaria; and a second co-dopant comprising at least one of lutetia, scandia, ceria, gadolinia, neodymia, or europia.

First claim

What is claimed is:

1. A method comprising:
controlling, by a computing device, a vacuum pump to evacuate a vacuum chamber to high vacuum;
controlling, by the computing device, a coating material source to provide a first coating material to a plasma spray device at a first feed rate, the first coating material having a composition selected so that a first layer from the first coating material comprises a rare earth disilicate, between about 0.1 wt. % and about 3 wt. % alumina, and a microstructure having less than about 10 vol. % porosity, and the first feed rate being selected to result in a substantially dense microstructure for the first layer;
controlling, by the computing device, the plasma spray device to deposit the first layer on a substrate in the vacuum chamber using plasma spray physical vapor deposition, wherein the first layer comprises the rare earth disilicate, between about 0.1 wt. % and about 3 wt. % alumina, and the microstructure having less than about 10 vol. % porosity;
controlling, by the computing device, the coating material source to provide a second coating material to the plasma spray device at a second feed rate, the second coating material having a composition selected so that a second layer formed on the first layer from the second coating material comprises a rare earth monosilicate or a thermal barrier coating composition comprising a base oxide comprising zirconia or hafnia; a primary dopant comprising ytterbia; a first co-dopant comprising samaria; and a second co-dopant comprising at least one of lutetia, scandia, ceria, gadolinia, neodymia, or europia; and
controlling, by the computing device, the plasma spray device to deposit the second layer on the first layer using plasma spray physical vapor deposition, wherein the second layer comprises the rare earth monosilicate or the thermal barrier coating composition comprising the base oxide comprising zirconia or hafnia; the primary dopant comprising ytterbia; the first co-dopant comprising samaria; and the second co-dopant comprising at least one of lutetia, scandia, ceria, gadolinia, neodymia, or europia.

2. The method of claim 1 , wherein the first coating material comprises excess silica compared to the rare earth disilicate.

3. The method of claim 1 , wherein at least one of the first coating material or the second coating material further comprises at least one of alumina, at least one alkali oxide, or at least one alkaline earth oxide.

4. The method of claim 1 , wherein the first layer and the second layer are deposited on at least one surface of the substrate that is not in a line-of-sight relationship with the plasma spray device.

5. The method of claim 1 , wherein:
the second layer comprises the thermal barrier coating composition comprising the base oxide comprising zirconia or hafnia; the primary dopant comprising ytterbia; the first co-dopant comprising samaria; and the second co-dopant comprising at least one of lutetia, scandia, ceria, gadolinia, neodymia, or europia; and
the second coating material comprises the base oxide comprising zirconia or hafnia; the primary dopant comprising ytterbia; the first co-dopant comprising samaria; and the second co-dopant comprising at least one of lutetia, scandia, ceria, gadolinia, neodymia, or europia.

6. The method of claim 1 , wherein the second layer comprises the rare earth monosilicate, and wherein the second coating material comprises excess silica compared to the rare earth monosilicate.

7. The method of claim 1 , further comprising:
controlling, by the computing device, the coating material source to provide a third coating material to the plasma spray device at a third feed rate, the third coating material having a composition selected so that a third layer formed on the second layer from the third coating material comprises the thermal barrier coating composition comprising the base oxide comprising zirconia or hafnia; the primary dopant comprising ytterbia; the first co-dopant comprising samaria; and the second co-dopant comprising at least one of lutetia, scandia, ceria, gadolinia, neodymia, or europia; and
controlling, by the computing device, the plasma spray device to deposit the third layer on the second layer using plasma spray physical vapor deposition, wherein the third layer comprises the thermal barrier coating composition comprising the base oxide comprising zirconia or hafnia; the primary dopant comprising ytterbia; the first co-dopant comprising samaria; and the second co-dopant comprising at least one of lutetia, scandia, ceria, gadolinia, neodymia, or europia.

8. The method of claim 7 , wherein:
the second coating material has a composition selected so that the second layer from the second coating material comprises the rare earth monosilicate, between about 0.1 wt. % and about 3 wt. % alumina, and a columnar microstructure.

9. The method of claim 1 , wherein the first coating material has a composition selected so that the first layer from the first coating material comprises the rare earth disilicate, between about 0.5 wt. % and about 3 wt. % alumina, and the microstructure having less than about 10 vol. % porosity.

10. The method of claim 1 , wherein the second coating material has a composition selected so that the second layer from the second coating material comprises the rare earth monosilicate, between about 0.1 wt. % and about 3 wt. % alumina, and a columnar microstructure.

11. The method of claim 1 , wherein the second coating material has a composition selected so that the second layer from the second coating material comprises the rare earth monosilicate, between about 0.5 wt. % and about 3 wt. % alumina, and a columnar microstructure.

12. The method of claim 1 , wherein the first coating material has a composition selected so that the first layer consists of the rare earth disilicate and alumina, and the microstructure having less than about 10 vol. % porosity.

13. The method of claim 1 , wherein the first coating material has a composition selected so that the first layer comprises the rare earth disilicate, between about 0.1 wt. % and about 3 wt. % alumina, and at least one alkali oxide or at least one alkaline earth oxide.

14. The method of claim 1 , wherein the second feed rate is selected to result in a columnar microstructure.

Assignees

• Rolls Royce Corp

Inventors

• Lee Kang N
• Gold Matthew R

Classifications

• H01J37/32458

  Vessel · CPC title

• C23C14/548

  Controlling the composition · CPC title

• C23C14/10

  Glass or silica · CPC title

• C23C14/083

  of refractory metals or yttrium · CPC title

• C23C4/02

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