Dislocator chemistries for turbine abradable or machinable coating systems
A coated article ( 20;60 ) includes a substrate ( 22 ) and a coating ( 24;62 ) on the substrate. The coating includes at least a first layer ( 30 ). The first layer has: a matrix ( 50 ); and a filler ( 52 ) at 2.0% to 40% by volume in the first layer. The first layer is selected from alkaline earth or transition metal (M) tungstates (MWO4); alkaline earth molybdates (MMoO 4 ); rare earth (RE) phosphates (REPO 4 ); and combinations thereof.
1. A coated article being a blade outer air seal comprising:
a substrate having a concave inner diameter (ID) surface; and
a coating on the substrate ID surface including at least a first layer,
wherein the first layer comprises:
a matrix; and
a filler at 2.0% to 40% by volume in the first layer selected from:
alkaline earth or transition metal tungstates;
alkaline earth molybdates;
rare earth phosphates; and
combinations thereof,
wherein the filler comprises at 5.0% to 30% by volume in the first layer one or a combination of:
CaWO 4 ;
BaWO 4 ;
BaMoO 4 ; and
SrMoO 4 .
2. The coated article of claim 1 wherein:
the filler is at 5.0% to 30.0% by volume in the first layer.
3. The coated article of claim 1 wherein:
the first layer has 5.0% to 20% porosity.
4. The coated article of claim 1 wherein:
the filler comprises at 5.0% to 30% by volume in the first layer:
CaWO 4 .
5. The coated article of claim 1 wherein:
the matrix comprises at least 50% by volume one or more rare earth, zirconium, or hafnium silicates.
6. The coated article of claim 5 wherein:
the rare earth silicate comprises at least one of yttrium monosilicate, yttrium disilicate, ytterbium monosilicate, and ytterbium disilicate.
7. The coated article of claim 6 further comprising:
an environmental barrier layer between the substrate and the first layer and comprising at least 50% by volume hafnium monosilicate.
8. The coated article of claim 1 wherein:
the substrate is a ceramic matrix composite.
9. The coated article of claim 1 further comprising:
a bond coat comprising a SiOC-BMAS mixture.
10. The coated article of claim 1 further comprising:
an environmental barrier layer between the substrate and the first layer and comprising at least 50% by volume one or more rare earth, zirconium, or hafnium silicates.
11. The coated article of claim 1 wherein:
the filler has a melting point of 1450° C. to 2100° C.
12. The coated article of claim 1 wherein:
the filler has a melting point within 400° C. of melting points of a majority of the matrix by weight.
13. The coated article of claim 1 wherein:
the coating includes a bond coat between the substrate and the first layer.
14. An engine comprising the blade outer air seal of claim 1 and further comprising:
a stage of blades adjacent the ID surface.
15. A method for manufacturing the blade outer air seal of claim 1 , the method comprising:
co-spraying:
a matrix-forming powder;
the filler as a powder; and
a fugitive powder; and
heating to remove the fugitive.
16. The method of claim 15 wherein one or more of:
the method comprises applying a bond coat prior to the spraying;
the spraying is dry powder; and
the matrix-forming powder and the filler powder are pre-blended.
17. A coated article being a blade outer air seal comprising:
a substrate having a concave inner diameter (ID) surface; and
a coating on the substrate ID surface including at least a bond coat and a first layer,
wherein:
the bond coat comprises a SiOC-BMAS mixture; and
the first layer comprises:
a matrix; and
a filler at 2.0% to 40% by volume in the first layer selected from:
alkaline earth or transition metal tungstates;
alkaline earth molybdates;
rare earth phosphates; and
combinations thereof.
18. The coated article of claim 17 wherein:
the coating includes a bond coat between the substrate and the first layer.
19. The coated article of claim 17 wherein:
the substrate is a ceramic matrix composite.