US 11,952,317 B2
CMAS-resistant barrier coatings
Ngunjoh Lawrence Ndamka, Derby (GB); Li Li, Carmel, IN (US); Stephanie Gong, Indianapolis, IN (US); Ann Bolcavage, Indianapolis, IN (US); Taylor K. Blair, Indianapolis, IN (US); and Robert Golden, Noblesville, IN (US)
Assigned to Rolls-Royce Corporation, Indianapolis, IN (US); and Rolls-Royce plc, London (GB)
Filed by Rolls-Royce Corporation, Indianapolis, IN (US); and Rolls-Royce plc, London (GB)
Filed on Oct. 18, 2019, as Appl. No. 16/657,504.
Claims priority of provisional application 62/876,272, filed on Jul. 19, 2019.
Claims priority of provisional application 62/796,977, filed on Jan. 25, 2019.
Claims priority of provisional application 62/747,535, filed on Oct. 18, 2018.
Prior Publication US 2020/0123071 A1, Apr. 23, 2020
This patent is subject to a terminal disclaimer.
Int. Cl. C04B 41/50 (2006.01); C04B 41/45 (2006.01); F01D 5/28 (2006.01)
CPC C04B 41/5024 (2013.01) [C04B 41/4543 (2013.01); F01D 5/284 (2013.01); F01D 5/288 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An article comprising:
a substrate of a gas turbine engine component;
and a barrier coating on the substrate, the barrier coating comprising:
a matrix comprising a rare-earth disilicate, the matrix extending from an inner interface facing the substrate to an outer surface opposite the inner interface;
and a graded volumetric distribution of rare-earth oxide rich (REO-rich) phase regions in the matrix along a direction from the inner interface to the outer surface,
wherein the REO-rich phase regions define bands in predetermined locations within the matrix,
wherein the REO-rich phase regions include rare-earth oxide in excess of stoichiometric rare-earth monosilicate,
wherein the matrix has a higher porosity in the first region nearer the outer surface than in the second region nearer the inner interface; wherein the barrier coating defines a coating thickness along the direction from the outer surface to the inner interface,
wherein the first region defines a first thickness along the direction, wherein the second region defines a second thickness along the direction, and wherein a ratio of the first thickness to the coating thickness is greater than 0.1, and
wherein a ratio of the second thickness to the coating thickness is greater than 0.1.