Structure and method for protecting a hybrid ceramic structure from moisture attack in a high temperature environment

• US 9,328,028 B2
• Filed: 07/22/2008
• Issued: 05/03/2016
• Est. Priority Date: 07/22/2008
• Status: Active Grant

• Current Assignee: Siemens Energy Incorporated (Siemens AG)
• Original Assignee: Siemens Energy Incorporated (Siemens AG)
• Inventors: Lane, Jay E., Merrill, Gary B.
• Primary Examiner(s): Ducheneaux, Frank D
• Application Number:
  US12/177,531
• Publication Number:
  US 20100021713A1
• Time in Patent Office: 2,842 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B32B 18/00 Layered products essentially comprising ceramics, e.g. refractory products
• CPC Class Codes: C04B 28/34 containing cold phosphate binders
• CPC Class Codes: C04B 35/803 The matrix of the ceramic products consisting of oxides only
• CPC Class Codes: C04B 41/009 characterised by the material treated
• CPC Class Codes: C04B 41/4535 applied as a solution, emulsion, dispersion or suspension
• CPC Class Codes: C04B 41/457 Non-superficial impregnation or infiltration of the substrate
• CPC Class Codes: C04B 41/5024 Silicates C04B41/5022 takes precedence; silico-fluorides C04B41/5018
• CPC Class Codes: C04B 41/5025 with ceramic materials copper oxide or solid solutions thereof C04B41/5074
• CPC Class Codes: C04B 41/5032 Aluminates aluminate spinels C04B41/5046
• CPC Class Codes: C04B 41/5042 Zirconium oxides or zirconates; Hafnium oxides or hafnates
• CPC Class Codes: C04B 41/5044 Hafnates
• CPC Class Codes: C04B 41/5045 Rare-earth oxides
• CPC Class Codes: F01D 5/282 Selecting composite materials, e.g. blades with reinforcing filaments
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]

Abstract

A hybrid ceramic structure and a method for protecting the hybrid ceramic structure from moisture attack in a high temperature combustion environment are provided. The structure includes a ceramic matrix composite (CMC) substrate (12). A thermal insulation material (14) is disposed on the substrate. A vapor resistant material (20) is applied through at least one surface of the hybrid ceramic structure while the hybrid ceramic structure is in a bisque condition that provides a degree of porosity to the hybrid ceramic structure so that the vapor resistant material is infiltrated through interstices available within a thickness of the hybrid ceramic structure.

Claims

1. A hybrid ceramic structure for use in a high temperature combustion environment containing moisture, the structure comprising:

a ceramic matrix composite (CMC) substrate;

a thermal insulation material disposed on the substrate,

the CMC substrate and the thermal insulation material comprising respective materials susceptible to recession when subjected to temperatures of approximately 1,500°

C. and higher in a combustion environment containing moisture and having respective subsurface cracks or fractures which are inaccessible from respective outward surfaces of the hybrid ceramic structure; and

a coating of water vapor resistant material on respective inner surfaces of at least some of the cracks or fractures in the CMC substrate to form respective moisture-resistant layers onto the respective inner surfaces of said at least some of the cracks or fractures as the hybrid ceramic structure transitions from a bisque condition to a fully fired condition.

2. The hybrid ceramic structure of claim 1, wherein the coating of water vapor resistant material ranges in thickness from 0.11 microns to 50 microns on the respective inner surfaces of the cracks or fractures in the CMC substrate.

3. The hybrid ceramic structure of claim 1, wherein the water vapor re-sistant material is selected from the group consisting of a pyrochlore structure;

HfSiO₄;

ZrSiO₄;

Y₂Si₂O₇;

Y₂O₃;

ZrO₂, HfO₂;

yttria and/or ZrO₂ stabilized by at least one rare earth element;

yttria and/or HfO₂ stabilized by at least one rare earth element;

yttria and/or ZrO₂/HfO₂ stabilized by at least one rare earth element;

a rare earth silicate of the form RE₂Si₂O₇;

a rare earth oxide of the form RE₂O₃; and

a rare earth zirconate or hafnate of the form RE₄Zr₃O₁₂ or RE₄Hf₃O₁₂, wherein the rare earth element is selected from the group consisting of;

Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

4. The hybrid ceramic structure of claim 1, wherein the water vapor resistant material fills at least some of the cracks or fractures in the CMC substrate.

5. The hybrid ceramic structure of claim 1, wherein the water vapor resistant material partly fills at least some of the cracks or fractures in the CMC substrate.

6. The hybrid ceramic structure of claim 1, wherein the water vapor resistant material forms a coating of water vapor resistant material on respective inner surfaces of at least some of the cracks or fractures in the thermal insulation material to form respective moisture-resistant layers onto the respective inner surfaces of said at least some of the cracks or fractures in the thermal insulation material during the transition.

7. The hybrid ceramic structure of claim 6, wherein the water vapor resistant material fills at least some of the cracks or fractures in the thickness of the thermal insulation material.

8. The hybrid ceramic structure of claim 6, wherein the water vapor resistant material partly fills at least some of the cracks or fractures in the thickness of the thermal insulation material.

11. The hybrid ceramic structure of claim 6, wherein the water vapor resistant material partly fills at least some of the cracks or fractures in the CMC substrate.

12. The hybrid ceramic structure of claim 6, wherein the water vapor resistant material forms a coating of water vapor resistant material on respective inner surfaces of at least some of the cracks or fractures in the thermal insulation material to form respective moisture-resistant layers onto the respective inner surfaces of said at least some of the cracks or fractures in the thermal insulation material during the transition.

13. The hybrid ceramic structure of claim 12, wherein the water vapor resistant material fills at least some of the cracks or fractures in the thickness of the thermal insulation material.

14. The hybrid ceramic structure of claim 12, wherein the water vapor resistant material partly fills at least some of the cracks or fractures in the thickness of the thermal insulation material.

9. A hybrid ceramic structure for use in a high temperature combustion environment containing moisture, the structure comprising:

a ceramic matrix composite (CMC) substrate;

a thermal insulation material disposed on the substrate,

the CMC substrate and the thermal insulation material comprising respective materials susceptible to recession when subjected to high temperature water vapor and having respective subsurface cracks or fractures which are inaccessible from respective outward surfaces of the hybrid ceramic structure,

wherein the CMC substrate comprises a material selected from the group consisting of silica-based materials, silica-based non-oxides, oxide matrix composites, mullite, aluminosilicate, alumina, silicon carbide composites, and silicon nitride composites, and

wherein the thermal insulation material comprises a material selected from the group consisting of mullite, mullite and stabilized zirconia, mullite and alumina, alumina, stabilized zirconia, ceria, and refractory forms of aluminum phosphate; and

a coating of water vapor resistant material on respective inner surfaces of at least some of the cracks or fractures in the CMC substrate to form respective moisture-resistant layers onto the respective inner surfaces of said at least some of the cracks or fractures as the hybrid ceramic structure transitions from a bisque condition to a fully fired condition.

10. The hybrid ceramic structure of claim 9, wherein the water vapor resistant material fills at least some of the cracks or fractures in the CMC substrate.