Integral Ceramic Matrix Composite Fastener With Polymer Rigidization

Patent metadata

Field	Value
Publication number	US-2016265389-A1
Application number	US-201514686842-A
Country	US
Kind code	A1
Filing date	Apr 15, 2015
Priority date	May 8, 2014
Publication date	Sep 15, 2016
Grant date	—

Abstract

A method of forming an integral fastener for a ceramic matrix composite component comprises the steps of forming a fiber preform, applying a polymer material to the fiber preform to form a rigid preform structure, machining an opening in the rigid preform structure, forming a fiber fastener, inserting the fiber fastener into the opening, removing the polymer material, and infiltrating a matrix material into the rigid preform structure and fiber fastener to form a ceramic matrix composite component with an integral fastener. A gas turbine engine is also disclosed.

First claim

1 . A method of forming an integral fastener for a ceramic matrix composite component comprising the steps of:
(a) forming a fiber preform; (b) applying a polymer material to the fiber preform to form a rigid preform structure; (c) machining an opening in the rigid preform structure; (d) forming a fiber fastener; (e) inserting the fiber fastener into the opening; (f) removing the polymer material; and (g) infiltrating a matrix material into the rigid preform structure and fiber fastener to form a ceramic matrix composite component with an integral fastener.

2 . The method according to claim 1 wherein step (f) includes oxidizing the polymer material from the rigid preform structure prior to step (g).

3 . The method according to claim 1 wherein step (g) includes using a chemical vapour infiltration process.

4 . The method according to claim 1 wherein step (a) includes forming the preform to be a gas turbine engine component, and wherein step (g) includes integrally forming the fastener and ceramic matrix composite component to provide a single-piece gas turbine engine component and fastener without any gaps between a head of the fastener and the ceramic matrix composite component.

5 . The method according to claim 1 wherein step (a) is accomplished using at least one of the following methods: two dimensional fabric lay-up, three dimensional weaving, knotting, or braiding.

6 . The method according to claim 1 wherein step (c) includes machining the opening to be wider at one surface of the ceramic matrix composite component than at an opposite surface to accommodate a head of the fastener formed in step (d).

7 . The method according to claim 1 wherein step (d) includes weaving the fastener from fibers.

8 . The method according to claim 1 wherein
step (a) includes forming the preform to be a gas turbine engine component,
step (d) includes forming the fastener to include a head portion and a foot portion,
step (c) includes forming the opening to be wider at one surface such that the head portion does not fall through the opening during step (e), and
(h) machining the foot portion of the fastener to receive a connecting structure subsequent to step (g) such that the fastener can be used to attach the gas turbine engine component to an engine support structure when the connecting structure is installed on the foot portion.

9 . The method according to claim 1 wherein step (d) includes forming the fastener from a ceramic matrix composite fiber material comprising a two-dimensional fabric lay-up.

10 . A method of forming an integral fastener for a ceramic matrix composite component comprising the steps of:
(a) forming a fiber preform; (b) rigidizing the preform with a polymer based material to provide a rigid preform structure; (c) machining an opening in the rigid preform structure; (d) weaving a fiber fastener; (e) inserting the fiber fastener into the opening; (f) oxidizing the rigid perform structure to remove the polymer based material; and (g) infiltrating a matrix material into the rigid preform structure and fiber fastener to form a ceramic matrix composite component with an integral fastener.

11 . The method according to claim 10 wherein step (g) includes using a chemical vapour infiltration process, polymer impregnation pyrolysis process, a slurry impregnation process, and/or a glass transfer molding process.

12 . The method according to claim 10 wherein
step (d) includes forming the fiber fastener to have a head portion and a foot portion that has a smaller width than the head portion,
step (c) includes machining the opening to be wider at one surface of the ceramic matrix composite component than at an opposite surface to accommodate the head portion formed in step (d), and
(h) machining the foot portion of the fiber fastener to receive a connecting structure subsequent to step (g).

13 . The method according to claim 10 including forming the fiber preform as a gas turbine engine component.

14 . A gas turbine engine component comprising:
a gas turbine engine component body formed of a ceramic matrix composite material having at least one fastener integrally formed with the gas turbine engine component body as a single-piece structure, wherein the gas turbine engine component body initially comprises a rigidized preform structure formed from a polymer material; and an engine support structure, wherein the at least one fastener connects the gas turbine engine component body to the engine support structure.

15 . The gas turbine engine component according to claim 14 wherein the rigidized preform structure has an opening to receive the fastener, and wherein the fastener initially comprises a separate woven fastener formed from a fiber based material, and wherein the woven fastener is received within the opening of the rigidized preform and subsequently infiltrated with a matrix material to form the single-piece structure as a finished component.

16 . The gas turbine engine component according to claim 15 wherein the rigidized preform structure includes the polymer based material prior to forming the opening.

17 . The gas turbine engine component according to claim 16 wherein the single-piece structure that forms the finished component does not include the polymer based material.

18 . The gas turbine engine component according to claim 14 wherein the gas turbine engine component body comprises one of a combustion liner or nozzle seal.

19 . The gas turbine engine component according to claim 18 wherein the engine support structure comprises a metal plate.

Assignees

• United Technologies Corp

Inventors

• Jarmon David C

Classifications

• F01D25/28 Primary

  Supporting or mounting arrangements, e.g. for turbine casing · CPC title

• C04B35/62227

  obtaining fibres · CPC title

• B28B11/12

  for removing parts of the articles by cutting · CPC title

• C04B2235/48

  Organic compounds becoming part of a ceramic after heat treatment, e.g. carbonising phenol resins · CPC title

• C04B35/76

  Fibres, filaments, whiskers, platelets, or the like · CPC title