Method and system for detecting exposure of composites to high-temperature

Patent metadata

Field	Value
Publication number	US-9372177-B2
Application number	US-201313840980-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Mar 15, 2013
Publication date	Jun 21, 2016
Grant date	Jun 21, 2016

Abstract

A method of detecting high-temperature exposure of a composite may include applying a composition comprising an adduct suitable for detecting heat and/or mechanical stress in a composite, wherein the adduct reverts to first and second adduct components after exposure of the composition to a temperature of from about 190° C. to about 260° C. to a surface of the composite; exposing the surface to which the composition has been applied to ultraviolet light; and measuring fluorescence of the composition.

First claim

What is claimed is:

1. A system, comprising:
a composite having a surface;
an excitation source for transmitting light of a first wavelength onto the surface of the composite, the surface including a repair composition having an adduct that detects heat in the composite;
a mounting plate defining at least one aperture for the passage of light;
a hood mountable upon the surface of the composite by the mounting plate, wherein the hood includes an inside portion;
a detector positioned within the inside portion of the hood, wherein the detector receives a fluorescence generated by the adduct indicating one of an over-heating and an out-of-spec heating condition of the repair composition; and
a controller in communication with the detector to receive the fluorescence detected by the detector, wherein the controller determines if the repair composition experiences at least one of the over-heating and the out-of-spec heating condition based on the fluorescence generated by the adduct during curing of the repair composition.

2. The system of claim 1 , wherein the excitation source is a source of ultraviolet light.

3. The system of claim 1 , wherein the excitation source is a laser.

4. The system of claim 1 , wherein the detector is one or more of a visible light camera, an infrared light camera, and a multi-filter imager.

5. The system according to claim 4 , wherein the multi-filter imager is one or more of a high-speed gated intensifying camera, a photomultiplier tube, and a single line spectrometer.

6. The system of claim 1 , further comprising an excitation beam steering mechanism configured to direct the light of the first wavelength onto one or more predetermined areas on the surface of the composite.

7. The system of claim 1 , wherein the controller automates fluorescence detection by the detector, and executes software and hardware routines to systematically scan the surface of the composite.

8. The system of claim 1 , wherein the controller actuates the excitation source to control emission of the light of the first wavelength.

9. The system of claim 1 , wherein the adduct reverts to first and second adduct components after exposure to a predefined range of temperatures.

10. The system of claim 1 , wherein the fluorescence of the adduct generates a distinct signature to indicate the over-heating and the out-of-spec heating condition of the repair composition.

11. A method of repairing a composite material having a damaged region, the method comprising:
applying a repair composition to the damaged region of the composite material, wherein the repair composition includes an adduct incorporated therein and the adduct detects heat in the composite material;
providing a system including an excitation source for transmitting light of a first wavelength onto the damaged region of the composite material, a mounting plate defining at least one aperture for the passage of light, a hood mountable upon the composite material by the mounting plate including an inside portion, a detector positioned within the inside portion of the hood that receives a fluorescence generated by the adduct indicating one of an over-heating and an out-of-spec heating condition of the repair composition, and a controller in communication with the detector to receive the fluorescence detected by the detector;
exposing the composite material and the damaged region to the light of the first wavelength to cause the adduct to generate a fluorescence indicating one of the over-heating and the out-of-spec heating condition of the repair composition;
measuring the fluorescence of the composite material and the damaged region; and
determining, by the controller, if the repair composition experiences at least one of the over-heating and the out-of-spec heating condition based on the fluorescence generated by the adduct during curing of the repair composition.

12. The method of claim 11 , wherein the adduct is added as one of: a resin in a repair pre-preg, a resin in a pre-cured doubler surface ply, an adhesive for bonded repairs, and an adhesive for scarfed repairs.

13. The method of claim 11 , wherein the fluorescence of the adduct generates a distinct signature to indicate the over-heating and the out-of-spec heating condition of the repair composition.

14. The method of claim 11 , wherein the composite material is part of an aircraft fuselage.

15. The method of claim 11 , wherein the specified light is ultraviolet light.

16. The method of claim 11 , wherein the adduct reverts to first and second adduct components after exposure to a predefined range of temperatures.

17. The method of claim 12 , wherein the predefined range of temperatures range from about 190° C. to about 260° C.

18. The method of claim 11 , wherein the detection device is selected from the group consisting of at least one of a: a visible light camera, an infrared camera, and a multi-filter imager.

19. The method of claim 11 , comprising executing software and hardware routines to systematically scan a surface of the composite material by the controller.

Assignees

• Boeing Co

Inventors

• Georgeson Gary E
• Watson Megan N
• Safai Morteza

Classifications

• G01N2021/8472

  Investigation of composite materials · CPC title

• C09D5/26 Primary

  Thermosensitive paints · CPC title

• G01N21/91

  using penetration of dyes, e.g. fluorescent ink · CPC title

• G01K11/20

  using thermoluminescent materials (G01K11/32 takes precedence) · CPC title

• G01N31/229 Primary

  for investigating time/temperature history · CPC title