	US 12,012,869 B2
	Part coated with a composition for protection against CMAS with controlled cracking, and corresponding treatment method
Luc Bianchi, Moissy-Cramayel (FR); Aurélien Joulia, Moissy-Cramayel (FR); André Hubert Louis Malie, Moissy-Cramayel (FR); and Benjamin Dominique Roger Joseph Bernard, Moissy-Cramayel (FR)
Assigned to SAFRAN, Paris (FR)
Appl. No. 16/958,422
Filed by SAFRAN, Paris (FR)
PCT Filed Dec. 26, 2018, PCT No. PCT/FR2018/053549 § 371(c)(1), (2) Date Dec. 10, 2020, PCT Pub. No. WO2019/129996, PCT Pub. Date Jul. 4, 2019.
Claims priority of application No. 1763278 (FR), filed on Dec. 27, 2017.
Prior Publication US 2021/0140327 A1, May 13, 2021
Int. Cl. C04B 41/89 (2006.01); C04B 41/00 (2006.01); C04B 41/50 (2006.01); C04B 41/52 (2006.01); F01D 5/28 (2006.01); F01D 25/00 (2006.01)

CPC F01D 5/288 (2013.01) [C04B 41/009 (2013.01); C04B 41/5024 (2013.01); C04B 41/5042 (2013.01); C04B 41/5072 (2013.01); C04B 41/522 (2013.01); C04B 41/89 (2013.01); F01D 25/00 (2013.01); F05D 2220/30 (2013.01); F05D 2230/31 (2013.01); F05D 2230/90 (2013.01)]

11 Claims

1. A turbomachine part comprising:

a substrate of metallic material, or of composite material; and

a protective coating layer against the infiltration of compounds of the oxides of calcium, magnesium, aluminum or silicon type, referred to as CMAS type, the coating layer at least partially covering the surface of the substrate,

wherein the protective coating layer comprises a plurality of elementary layers,

wherein elementary layers of a first set of the plurality of elementary layers are interposed between elementary layers of a second set of the plurality of elementary layers, each elementary layer of the first set and each elementary layer of the second set comprising an anti-CMAS compound, and

wherein each contact zone between an elementary layer of the first set and an elementary layer of the second set forms an interface promoting a propagation of cracks along said interface,

wherein each elementary layer of the first set has a toughness which differs by at least 0.7 MPa·m^1/2from the toughnesses of all elementary layers of the second set, or

wherein each elementary layer of the first set has a coefficient of thermal expansion which differs by at least 3.5 10⁻⁶K⁻¹from the coefficients of thermal expansion of all elementary layers of the second set.