Ceramic matrix composite airfoil repair

Patent metadata

Field	Value
Publication number	US-11028696-B2
Application number	US-201715670151-A
Country	US
Kind code	B2
Filing date	Aug 7, 2017
Priority date	Aug 7, 2017
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

Methods for repairing composite components are provided. For instance, one exemplary method includes machining an interlocking feature into an existing component. A replacement material or core having an interlocking feature complementary to the interlocking feature of the existing component is then joined with the component. The interlocking features interlock to form a joint. The joint is then overlaid with one or more plies to rebuild the outer surface of the component and seal the joint. A bonding process can be used to chemically bond the newly joined parts together. Repaired composite components are also provided.

First claim

What is claimed is:

1. A method for repairing a component having a damaged region, the component formed from a composite material and defining a span length that extends from a first end of the component to a second end of the component, and a reference line that is defined midway between the first end and the second end, the damaged region being closer to the second end than the first end, wherein the component is an airfoil for use in a gas turbine engine, the method comprising:
joining a replacement material with the component, the replacement material having a tip end, a connection end, a leading edge, and a trailing edge, wherein the component comprises an interlocking feature and the connection end of the replacement material comprises an interlocking feature complementary to the interlocking feature of the component, wherein when the replacement material is joined with the component, the interlocking features of the replacement material and the component interlock to form a joint that defines a joint width and a joint length, the joint width being perpendicular to the joint length and the joint length spanning a width of the component;
overlaying the joint with a plurality of plies, wherein overlaying the joint comprises laying a first ply over the joint on a pressure side of the airfoil and laying a second ply over the joint on a suction side of the airfoil; and
bonding the component with the replacement material and bonding the plurality of plies with the component and the replacement material;
wherein the joint is only between the reference line and the first end of the component;
wherein the first ply extends beyond the leading edge of the replacement material;
wherein overlaying the joint with a plurality of plies comprises laying one or more ply layers on the pressure side of the airfoil and laying one or more ply layers on the suction side of the airfoil, wherein the number of ply layers on the pressure side of the airfoil does not equal the number of ply layers on the suction side of the airfoil.

2. The method of claim 1 , wherein at least one of the plurality of plies extends from a center of the joint width in a first direction a distance equal to the joint width and extends from the center of the joint width in a second direction a distance equal to the joint width, the first direction opposite the second direction.

3. The method of claim 1 , wherein the component is formed from a polymer matrix composite (PMC) material.

4. The method of claim 1 , wherein the interlocking feature of the component is one or more dovetails and the interlocking feature of the replacement material is one or more dovetails.

5. The method of claim 1 , wherein the interlocking feature of the component and the interlocking feature of the replacement material are configured to counteract tensile forces.

6. The method of claim 1 , wherein the interlocking feature of the component and the interlocking feature of the replacement material are configured to counteract shear forces.

7. The method of claim 1 , wherein the step of bonding comprises inserting the component, the replacement material, and the plurality of plies in an autoclave to cause the component to chemically bond with the replacement material and the plurality of plies to chemically bond with the component and the replacement material.

8. The method of claim 1 , wherein the first ply mates with the second ply.

9. The method of claim 1 , wherein at least one of the plurality of plies has a different length than another one of the plurality of plies.

10. The method of claim 1 , further comprising machining the component and the replacement material after boding the component with the replacement material.

Assignees

• Gen Electric

Inventors

• Roberts Herbert Chidsey
• Taxacher Glenn Curtis

Classifications

• B29C73/04

  using preformed elements · CPC title

• Y02T50/60

  Efficient propulsion technologies, e.g. for aircraft · CPC title

• F05D2230/80

  Repairing, retrofitting or upgrading methods · CPC title

• F01D5/282

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

• B23P6/005

  using only replacement pieces of a particular form · CPC title