Method of facilitating visual detection of a crack in a component of a gas turbine engine

Patent metadata

Field	Value
Publication number	US-9804058-B2
Application number	US-201414191689-A
Country	US
Kind code	B2
Filing date	Feb 27, 2014
Priority date	Feb 27, 2014
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

A component of a gas turbine engine comprises a substrate, a corrosion resistant top layer, and an intermediate corrodible layer disposed between the corrosion resistant top layer and the substrate. When corroding, the intermediate layer has a color contrasting with a color of the top layer. A method of detecting a crack when it penetrated the top layer in a component of a gas turbine engine having a corrosion resistant top layer and an intermediate corrodible layer comprises, in sequence, observing that at least one area of the component has a color contrasting with that of the top layer; determining that the color of the at least one area is a result of corrosion of the intermediate corrodible layer; and determining that the top layer has a crack as a result of determining corrosion of the intermediate layer. A method of facilitating crack detection in a component is also presented.

First claim

The invention claimed is:

1. A method of facilitating crack detection in a component of a gas turbine engine, the method comprising:
obtaining a substrate of the component;
depositing an intermediate corrodible layer onto the substrate; and
depositing a galvanically non-compatible corrosion resistant top layer onto the intermediate corrodible layer, wherein, when a crack in the top layer exposes the intermediate corrodible layer, the intermediate corrodible layer galvanically corrodes in a color contrasting with a color of the top layer facilitating visual crack detection.

2. The method as defined in claim 1 , wherein depositing the intermediate corrodible layer onto the substrate comprises one of coating and plating the intermediate corrodible layer onto the substrate.

3. The method as defined in claim 1 , wherein depositing the galvanically non-compatible corrosion resistant top layer onto the intermediate corrodible layer comprises one of coating and plating the galvanically non-compatible corrosion resistant top layer onto the intermediate corrodible layer.

4. The method as defined in claim 1 , wherein depositing the galvanically non-compatible corrosion resistant top layer comprises depositing a metal top layer.

5. The method as defined in claim 1 , wherein depositing the intermediate corrodible layer comprises depositing a ferrous intermediate corrodible layer.

6. The method as defined in claim 1 , wherein when corroding occurs, the intermediate corrodible layer expands on corrosion.

7. The method as defined in claim 1 , wherein providing the substrate comprises providing an aluminum alloy substrate.

8. The method as defined in claim 1 , wherein depositing the intermediate corrodible layer onto the substrate includes stiffening and strengthening the component.

9. The method as defined in claim 1 , wherein the intermediate layer is a structural load supporting element of the component.

Assignees

• Pratt & Whitney Canada

Inventors

• Cheung Kin-Leung

Classifications

• F05D2260/80

  Diagnostics · CPC title

• F01D5/288

  Protective coatings for blades · CPC title

• F01D5/286

  Particular treatment of blades, e.g. to increase durability or resistance against corrosion or erosion (F01D5/288 takes precedence) · CPC title

• F01D5/284

  Selection of ceramic materials · CPC title

• F01D5/282

  Selecting composite materials, e.g. blades with reinforcing filaments · CPC title