Laminate structure fabricated using chemical vapor infiltration (cvi)

Patent metadata

Field	Value
Publication number	US-2016251272-A1
Application number	US-201514633347-A
Country	US
Kind code	A1
Filing date	Feb 27, 2015
Priority date	Feb 27, 2015
Publication date	Sep 1, 2016
Grant date	—

Abstract

A preform can be subject to chemical vapor infiltration (CVI) to define a ceramic matrix composite (CMC) structure, a supplemental preform can be added to the CMC structure to define an expanded structure and CVI can be performed using the expanded structure. The adding of a supplemental preform and performing CVI using the expanded structure can be repeated.

First claim

What is claimed is:

1 . A method of fabricating a laminate structure, the method comprising:
subjecting a preform to chemical vapor infiltration (CVI) to define a densified ceramic matrix composite (CMC) structure; adding a supplemental preform to the CMC structure to define an expanded structure; performing CVI using the expanded structure.

2 . The method of claim 1 , wherein the method includes repeating the adding and the performing.

3 . The method of claim 1 , wherein the method includes performing the method so that a resulting structure is shaped into a specified shape.

4 . The method of claim 3 , wherein the specified shape is of a turbine component.

5 . The method of claim 4 , wherein the turbine component is selected from the group consisting of a combustion liner, a vane, a blade, a nozzle, a bucket, a transition piece, a turbine center frame, and a shroud.

6 . The method of claim 4 , wherein performing the method so that the resulting structure is the specified shape of a turbine component includes using a mold.

7 . The method of claim 1 , wherein one or more of the preform or the supplemental preform include unidirectional fibers.

8 . The method of claim 7 , wherein the unidirectional fibers include a fiber coating.

9 . The method of claim 7 , wherein the unidirectional fibers include SiC.

10 . The method of claim 1 , wherein the preform and supplemental preform have an open porosity content of about 20% to about 80%.

11 . The method of claim 1 , wherein the performing CVI includes depositing a material selected from the group consisting of SiC, Si 3 N 4 , BN, B 4 C, MoSi 2 , SiO 2 , SiOC, SiNC, and SiONC, within a porosity of the expanded structure.

13 . The method of claim 1 , wherein the method includes shaping the preform to define a shape of a surface of a turbine component.

14 . The method of claim 1 , wherein the method includes using the densified CMC structure as a mold to shape the supplemental preform.

15 . The method of claim 1 , wherein one or more of the subjecting or performing includes stopping infiltration short of an amount yielding maximum densification.

16 . A laminate structure comprising:
a first CMC structure joined to a second CMC structure adjacent to the first CMC structure; wherein a density profile of the first CMC structure is discontinuous with a density profile of the second CMC structure.

17 . The laminate structure of claim 16 , wherein the first CMC structure has a first thickness having a U shaped density profile, and the second CMC structure has a second thickness having a density profile that is not U shaped.

18 . The laminate structure of claim 16 , wherein the laminate structure includes a center thickness section, a first end thickness section and a second end thickness section, wherein the center thickness section has a U shaped density profile, and the first end thickness section and the second end thickness section have ramp shaped density profiles.

19 . The laminate structure of claim 16 , wherein a density at an interface between the first CMC structure and the second CMC structure is stepwise discontinuous.

20 . The laminate structure of claim 16 , shaped in a shape of a turbine component.

21 . The laminate structure of claim 16 , wherein the laminate structure includes a CMC structure defining an end surface of the laminate structure, wherein the CMC structure defining an end surface has a lower maximum density than a CMC structure of the laminate structure that does not define an end surface of the laminate structure.

22 . The laminate structure of claim 16 , wherein an end thickness section of the laminate structure has a lower maximum density than a center thickness section of the laminate structure.

Assignees

• Gen Electric

Inventors

• Weaver Jared Hogg
• Ramamurthi Badri Narayan

Classifications

• C04B35/14

  based on silica · CPC title

• C04B2235/775

  Products showing a density-gradient · CPC title

• B32B3/263

  characterised by a layer having non-uniform thickness · CPC title

• C04B35/565

  based on silicon carbide · CPC title

• C04B41/5066

  Silicon nitride · CPC title