Anti-cmas coating with dual reactivity

Patent metadata

Field	Value
Publication number	US-2021148238-A1
Application number	US-201816621568-A
Country	US
Kind code	A1
Filing date	Jun 11, 2018
Priority date	Jun 12, 2017
Publication date	May 20, 2021
Grant date	—

Abstract

A coated gas turbine engine part includes a substrate and a calcium-magnesium-alumino-silicate (CMAS) protection layer present on the substrate. The protection layer includes a first phase of a calcium-magnesium-alumino-silicate CMAS protection material capable of forming an apatite or anorthite phase in the presence of calcium-magnesium-alumino-silicates CMAS and a second phase including particles of at least one rare-earth REa silicate dispersed in the first phase.

First claim

1 . Coated gas turbine engine part comprising a substrate and at least one calcium-magnesium-alumino-silicate (CMAS) protection layer present on said substrate, the protective layer comprising a first phase of a calcium-magnesium-alumino-silicate (CMAS) protection material capable of forming an apatite or anorthite phase in the presence of calcium-magnesium-alumino-silicates (CMAS) and a second phase comprising particles of at least one rare-earth RP silicate dispersed in the first phase,
the calcium-magnesium-alumino-silicate (CMAS) protection material of the first phase capable of forming apatite or anorthite phases corresponding to one of the following materials or a mixture of several of the following materials: rare-earth zirconates RE b 2 Zr 2 O 7 , where RE b =Y (yttrium), La (lanthanum), Ce (cerium), Pr (praseodymium), Nd (neodymium), Pm (promethium), Sm (samarium), Eu (europium), Gd (gadolinium), Tb (terbium), Dy (dysprosium), Ho (holmium), Er (erbium), Tm (thulium), Yb (ytterbium), Lu (lutecium), fully stabilized zirconia, delta phases A 4 B 3 O 12 , where A=Y→Lu and B=Zr, Hf, composites Y 2 O 3 with ZrO 2 , yttrium and aluminium garnets (YAG), composites YSZ-Al 2 O 3 or YSZ-Al 2 O 3 —TiO 2 .

2 . The part according to claim 1 , wherein said at least one rare-earth silicate is a rare-earth monosilicate RE a 2 SiO 5 or a rare-earth disilicate RE a 2 Si 2 O 7 , wherein RE a is selected from: Y (yttrium), La (lanthanum), Ce (cerium), Pr (praseodymium), Nd (neodymium), Pm (promethium), Sm (samarium), Eu (europium), Gd (gadolinium), Tb (terbium), Dy (dysprosium), Ho (holmium), Er (erbium), Tm (thulium), Yb (ytterbium), Lu (lutecium).

3 . The part according to claim 1 , wherein the rare-earth RE a silicate particles dispersed in the calcium-magnesium-alumino-silicate (CMAS) protection layer have an average size between 5 nm and 50 μm.

4 . The part according to claim 1 , wherein the calcium-magnesium-alumino-silicate (CMAS) protection layer has a volume content of particles of said at least one rare-earth silicate between 1% and 80%.

5 . The part according to claim 4 , wherein the volume percentage of rare-earth RE a silicate ceramic particles present in the calcium-magnesium-alumino-silicate (CMAS) protection layer varies in the direction of the thickness of the protective layer, the volume percentage of rare-earth RE a silicate ceramic particles gradually increasing between a first zone of said layer adjacent to the substrate and a second zone of said layer remote from the first zone.

6 . The part according to claim 1 , wherein the calcium-magnesium-alumino-silicate (CMAS) protection layer has a thickness between 1 μm and 1000 μm.

7 . The part according to claim 1 , further comprising a thermal barrier layer interposed between the substrate and the calcium-magnesium-alumino-silicate (CMAS) protection layer.

8 . The part according to claim 1 , wherein the substrate is a nickel or cobalt-based superalloy and has on its surface an alumino-forming bond coat.

9 . Process for manufacturing a gas turbine engine part according to claim 1 , comprising at least one step of forming a calcium-magnesium-alumino-silicate (CMAS) protection layer directly on the substrate or on a thermal barrier layer present on the substrate, the forming step being performed with one of the following methods:
suspension plasma spraying from at least one suspension containing a powder or precursor of a calcium-magnesium-alumino-silicate (CMAS) protection material and a powder or precursor of a rare-earth RE silicate, high-velocity flame spraying from at least one suspension containing a powder or precursor of a calcium-magnesium-alumino-silicate (CMAS) protection material and a powder or precursor of a rare-earth RE silicate, atmospheric-pressure plasma spraying of a powder of a calcium magnesium alumino-silicate (CMAS) protection material in combination with suspension plasma spraying or high-velocity flame spraying from a solution containing a rare-earth RE silicate ceramic precursor or a rare-earth RE silicate ceramic powder in suspension.

10 . The part according to claim 2 , wherein the rare-earth RE a silicate particles dispersed in the calcium-magnesium-alumino-silicate (CMAS) protection layer have an average size between 5 nm and 50 μm.

Assignees

• Safran

Inventors

• Bianchi Luc
• Joulia Aurélien
• Bernard Benjamin Dominique Roger Joseph

Classifications

• F01D5/288 Primary

  Protective coatings for blades · CPC title

• C23C30/00

  Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process (C23C26/00, C23C28/00 take precedence) · CPC title

• C23C4/11

  Oxides · CPC title

• C23C4/134

  Plasma spraying · CPC title

• Y02T50/60

  Efficient propulsion technologies, e.g. for aircraft · CPC title