Composite turbine blade for high-temperature applications

Patent metadata

Field	Value
Publication number	US-9938838-B2
Application number	US-201514601311-A
Country	US
Kind code	B2
Filing date	Jan 21, 2015
Priority date	Jan 31, 2014
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

A composite turbine blade for high-temperature applications such as gas turbines or the like includes a root for mounting the blade in a corresponding circumferential assembly groove of a rotor and an airfoil connected to said root. An inner carrying structure is provided extending at least over a portion of the root as well as at least a portion of said airfoil. The inner carrying structure is made of a high strength eutectic ceramic and the airfoil is made of a ceramic matrix composite (CMC) material.

First claim

The invention claimed is:

1. A composite turbine blade comprising:
a root, the root configured to mount said blade in a corresponding circumferential assembly groove of a rotor;
an airfoil connected to said root,
an inner carrying structure extending from at least a portion of said root to a portion of said airfoil, said inner carrying structure connected to the airfoil and the root such that the inner carrying structure is positioned inside of an external surface of the root and positioned inside of an external surface of the airfoil, said inner carrying structure comprised of a eutectic ceramic material;
a joining mechanism coupling said airfoil to said inner carrying structure, said joining mechanism comprised of a sintered ceramic slurry at respective contact locations between said airfoil and said inner carrying structure that forms at least one joint between the inner carrying structure and the airfoil;
the root and airfoil fully enclosing all external surfaces of the inner carrying structure,
said airfoil comprised of a ceramic matrix composite (CMC) material.

2. The composite turbine blade according to claim 1 , wherein said airfoil is comprised of a fiber-reinforced material.

3. The composite turbine blade according to claim 1 , wherein said exterior surface of said root is comprised of an outer metal surface coating.

4. The composite turbine blade according to claim 1 , wherein the CMC material for said airfoil is directly shaped on said inner carrying structure in a shape of a predetermined form of the blade.

5. The composite turbine blade according to claim 1 , wherein said inner carrying structure has a shaped cross-section at an end of the inner carrying structure within the airfoil that is shaped for attachment to the airfoil.

6. The composite turbine blade according to claim 1 , wherein said root has a fir tree cross section for engagement in a corresponding cross-section of said assembly groove of the rotor.

7. The composite turbine blade according to claim 1 , wherein airfoil is mechanically fixed on the inner carrying structure.

8. The composite turbine blade according to claim 1 , wherein said airfoil has a hollow shape that defines inner cavities between respective contact locations with said inner carrying structure.

9. A composite turbine blade for a gas turbine comprising:
a root;
an airfoil, said airfoil comprised of a ceramic matrix composite (CMC) material;
an inner carrying structure extending from said root to said airfoil, said inner carrying structure connected to the airfoil and the root such that the inner carrying structure is positioned inside of an external surface of the root and positioned inside of an external surface of the airfoil, said inner carrying structure comprised of a eutectic ceramic material;
the external surface of the root comprised of a metal coating that coats at least a portion of the inner carrying structure positioned within the root;
the external surface of the airfoil comprised of the CMC material;
the airfoil connected to the inner carrying structure via a joining mechanism, the root and airfoil fully enclosing all external surfaces of the inner carrying structure, the joining mechanism comprising one of:
ceramic fasteners extending between the airfoil and the inner carrying structure,
metallic fasteners extending between the airfoil and the inner carrying structure,
pins extending from holes formed within the inner carrying structure to the airfoil,
inserts extending from holes formed within the inner carrying structure to the airfoil, and
a solid ceramic joint between the airfoil and the inner carrying structure, the solid ceramic joint comprising a sintered ceramic slurry.

10. The composite turbine blade of claim 9 , wherein the joining mechanism is the ceramic fasteners extending between the airfoil and the inner carrying structure.

11. The composite turbine blade of claim 9 , wherein the joining mechanism is the metallic fasteners extending between the airfoil and the inner carrying structure.

12. The composite turbine blade of claim 9 , wherein the joining mechanism is the pins extending from holes formed within the inner carrying structure to the airfoil.

13. The composite turbine blade of claim 9 , wherein the joining mechanism is the inserts extending from holes formed within the inner carrying structure to the airfoil.

14. The composite turbine blade of claim 9 , wherein the joining mechanism is the solid ceramic joint comprising the sintered ceramic slurry.

15. The composite turbine blade of claim 14 , wherein the airfoil has an inverted U shape that receives the inner carrying structure.

Assignees

• Ansaldo Energia Ip Uk Ltd

Inventors

• Witz Gregoire Etienne
• Stuer Michael
• Bossmann Hans-Peter

Classifications

• F01D5/282 Primary

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

• F01D5/20

  Specially-shaped blade tips to seal space between tips and stator {(F01D5/225 takes precedence)} · CPC title

• F05D2300/611

  Coating · CPC title

• F05D2300/6033

  Ceramic matrix composites [CMC] · CPC title

• F01D5/3053

  by means of pins · CPC title