US 11,655,543 B2
CMAS-resistant barrier coatings
Ngunjoh Lawrence Ndamka, Derby (GB); Li Li, Carmel, IN (US); Ann Bolcavage, Indianapolis, IN (US); Bruce Edward Varney, Greenwood, IN (US); and Sean E. Landwehr, Avon, IN (US)
Assigned to ROLLS-ROYCE CORPORATION, Indianapolis, IN (US); ROLLS-ROYCE PLC, London (GB); and ROLLS-ROYCE NORTH AMERICAN TECHNOLOGIES, INC., Indianapolis, IN (US)
Filed by Rolls-Royce Corporation, Indianapolis, IN (US); Rolls-Royce North American Technologies, Inc., Indianapolis, IN (US); and Rolls-Royce PLC, London (GB)
Filed on Aug. 8, 2018, as Appl. No. 16/57,984.
Claims priority of provisional application 62/542,550, filed on Aug. 8, 2017.
Prior Publication US 2019/0048475 A1, Feb. 14, 2019
Int. Cl. C23C 28/04 (2006.01); F01D 5/28 (2006.01); C23C 28/00 (2006.01)
CPC C23C 28/042 (2013.01) [C23C 28/321 (2013.01); C23C 28/3215 (2013.01); C23C 28/345 (2013.01); C23C 28/347 (2013.01); C23C 28/3455 (2013.01); F01D 5/288 (2013.01); F05D 2220/323 (2013.01); F05D 2240/12 (2013.01); F05D 2240/30 (2013.01); F05D 2300/21 (2013.01); F05D 2300/611 (2013.01)] 13 Claims
 
1. A method comprising:
predicting a composition of active components of calcium-magnesium-aluminum-silicate (CMAS) to be encountered by a high temperature mechanical system during use of the high temperature mechanical system, wherein the composition of active components of CMAS comprises a relative molar composition of at least two of calcium oxide, magnesium oxide, aluminum oxide, or silicon oxide; and
selecting a composition of a CMAS-resistant barrier coating layer based at least in part on the predicted composition of active components of CMAS, wherein, prior to exposure of the barrier coating to an operating environment of the high temperature mechanical system, the CMAS-resistant barrier coating layer comprises:
a base composition comprising at least one of a rare earth monosilicate or a rare earth disilicate;
at least one secondary oxide selected based on the predicted composition of active components of CMAS to reduce, compared to the base composition alone, at least one of:
a diffusion gradient of the active components of CMAS into the CMAS-resistant barrier coating layer; or
a reaction gradient of the active components of CMAS with the base composition of the CMAS-resistant barrier coating layer,
wherein the at least one secondary oxide comprises at least one of an oxide of a divalent element, an oxide of a trivalent element, or an oxide of a tetravalent element,
wherein the CMAS-resistant barrier coating layer comprises greater than 0 mol. % and less than about 7 mol. % of the at least one secondary oxide, and
wherein the at least one secondary oxide includes at least one of calcium oxide, barium oxide, magnesium oxide, aluminum oxide, or silicon oxide.