Turbine blade cooling channel formation

Patent metadata

Field	Value
Publication number	US-9273559-B2
Application number	US-201313790615-A
Country	US
Kind code	B2
Filing date	Mar 8, 2013
Priority date	Mar 8, 2013
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

Abstract

Embodiments of the invention relate generally to turbine blades and, more particularly, to the formation of cooling channels on a surface of a turbine blade and turbine blades including such cooling channels. In one embodiment, the invention provides a method of forming a cooling channel along a surface of a turbine blade, the method comprising: applying a first mask material to a first portion of a surface of a turbine blade; forming a first barrier layer atop the first mask material and atop a second portion of the surface of the turbine blade; removing the first mask material and the barrier layer atop the first mask material to expose the first portion of the surface of the turbine blade; and etching the first portion of the surface of the turbine blade to form a cooling channel along the surface of the turbine blade.

First claim

What is claimed is:

1. A method of forming a cooling channel along a surface of a turbine blade, the method comprising:
applying a first mask material to a first portion of a surface of a turbine blade;
forming a first barrier layer atop the first mask material and atop a second portion of the surface of the turbine blade;
removing the first mask material and the barrier layer atop the first mask material to expose the first portion of the surface of the turbine blade; and
etching the first portion of the surface of the turbine blade to form a cooling channel along the surface of the turbine blade.

2. The method of claim 1 , further comprising:
applying a metallic bond coat to the surface of the turbine blade sufficient to cover but not fill the cooling channel.

3. The method of claim 1 , further comprising:
forming a passage between the cooling channel and cooling source within the turbine blade.

4. The method of claim 1 , further comprising:
filling the cooling channel with a second mask material;
depositing a high-temperature metal layer atop the second mask material and the second portion of the surface of the turbine blade;
depositing a third mask material atop the high-temperature metal layer;
depositing a second barrier layer atop the third mask material and the high-temperature metal layer;
removing the third mask material and the second barrier layer atop the third mask material;
etching the high-temperature metal layer through to the second mask material; and
removing the second mask material.

5. The method of claim 4 , further comprising:
applying a metallic bond coat to the surface of the turbine blade sufficient to cover but not fill the cooling channel.

6. The method of claim 4 , wherein the cooling channel has a first width and etching the high-temperature metal layer includes etching the high-temperature metal layer to a second width that is less than the first width, such that at least a portion of the high-temperature metal layer extends over the cooling channel.

7. The method of claim 4 , wherein the high-temperature metal layer includes a porous metal layer.

8. The method of claim 4 , wherein depositing the high-temperature metal layer includes forming a porous metal layer by:
aluminizing the high-temperature metal layer;
converting the aluminized high-temperature metal layer to an aluminide layer; and
removing aluminum from the aluminide layer to form the porous metal layer.

9. The method of claim 8 , wherein aluminizing includes at least one of the following: dipping the high-temperature metal layer in an aluminum bath, spray depositing aluminum onto the high-temperature metal layer, or vapor depositing aluminum onto the high-temperature metal layer.

10. The method of claim 8 , wherein removing aluminum from the aluminide layer includes leaching aluminum from the aluminide layer using a caustic solution.

11. The method of claim 8 , further comprising:
oxidizing the porous metal layer.

12. The method of claim 1 , wherein the first mask material is selected from a group consisting of: photoresists and polymer materials.

13. The method of claim 1 , wherein the first barrier layer includes at least one material selected from a group consisting of: Titanium oxynitride, TiO 2 , TaO 2 , TiN, SiO 2 , aluminum oxide, and refractory metal oxide.

14. A method of coating a turbine blade, the method comprising:
aluminizing a metal layer of the turbine blade surface;
converting the aluminized metal layer to an aluminide layer; and
removing aluminum from the aluminide layer, forming a porous metal layer.

15. The method of claim 14 , further comprising:
oxidizing the porous metal layer.

16. The method of claim 15 , further comprising:
applying at least one of a bond coat or a thermal barrier coating to the oxidized porous metal layer.

17. The method of claim 14 , wherein the metal layer is selected from a group consisting of: a nickel-based superalloy of the turbine blade, a nickel-based alloy applied to the turbine blade surface, and a metallic bond coat atop the turbine blade surface.

18. The method of claim 14 , wherein:
aluminizing includes at least one of the following: dipping the metal layer in an aluminum bath, spray depositing aluminum onto the metal layer, or vapor depositing aluminum onto the metal layer;
converting the aluminized metal layer to an aluminide layer includes heating the aluminized metal layer to a temperature between about 660° C. and about 1200° C.; and
removing aluminum from the aluminide layer includes leaching aluminum from the aluminide layer using a caustic solution.

19. A turbine blade comprising:
a nickel-based superalloy airfoil;
an oxidized porous metal layer on a surface of the airfoil; and
at least one of a bond coat or a thermal barrier coating over the oxidized porous material.

20. The turbine blade of claim 19 , further comprising:
at least one cooling channel along the surface of the airfoil; and
at least one passage between the at least one cooling channel and a source of coolant within the turbine blade.

Assignees

• Gen Electric

Inventors

• Knorr David Bruce
• Morey Kathleen Blanche

Classifications

• F05D2300/514

  Porosity · CPC title

• F05D2260/204

  by the use of microcircuits · CPC title

• F05D2230/90

  Coating; Surface treatment · CPC title

• F05D2230/31

  Layer deposition · CPC title

• F05D2230/11

  by electrochemical methods · CPC title