LASER ULTRASOUND SYSTEM AND METHOD FOR INSPECTION OF A CONTOURED STRUCTURE

• US 20170010242A1
• Filed: 07/09/2015
• Published: 01/12/2017
• Est. Priority Date: 07/09/2015
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: GEORGESON, Gary E., SAFAI, Morteza
• Granted Patent: US 10,539,538 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01D 5/268 using optical fibres G01D5/28 - G01D5/38 take precedence
• CPC Class Codes: G01N 2291/0231 Composite or layered materials
• CPC Class Codes: G01N 2291/0258 Structural degradation, e.g. fatigue of composites, ageing of oils
• CPC Class Codes: G01N 29/043 in the interior, e.g. by shear waves
• CPC Class Codes: G01N 29/2418 using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046

Abstract

A method including ultrasonically scanning a structure with a laser ultrasound testing system where the structure is provided with an array of nanoscopic structures, the nanoscopic structures having a predetermined directional orientation, the nanoscopic structures disposed on a scanned surface of the structure, and determining if the structure meets a predetermined threshold. Aspects of this invention apply certain high emissivity coatings to structures for the purpose of significant improvement laser ultrasound inspection of those structures. The nanotechnology-based material in the coatings rapidly draws heat away, for maximum laser energy absorption while preventing surface heat damage to the composite surface from the laser beam.

Claims

1. A method comprising:

ultrasonically scanning a structure with a laser ultrasound testing system where the structure is provided with an array of nanoscopic structures, the nanoscopic structures having a predetermined directional orientation, the nanoscopic structures disposed on a scanned surface of the structure; and

determining if the structure meets a predetermined threshold.

2. The method of claim 1, further comprising directing incident energy from the laser ultrasound testing system into the structure using the array of nanoscopic structures.

3. The method of claim 1, wherein the array of nanoscopic structures comprise a nanotube coating, the method further comprising directing incident energy from the laser ultrasound testing system into the structure using the nanotube coating.

4. The method of claim 3, wherein the nanotube coating includes nanotubes arranged substantially perpendicular to the scanned surface of the structure.

5. The method of claim 1, further comprising dispersing heat generated by the laser ultrasound testing system on the structure.

6. The method of claim 1, wherein the laser ultrasound testing system is a low power fiber-based laser system.

7. The method of claim 1, further comprising coating the scanned surface with the array of nanoscopic structures.

8. A method comprising:

disposing a nanotube array on at least a portion of a structure;

directing incident energy of a laser ultrasound testing system into the structure with the nanotube array and generating a scan of the structure; and

determining if the structure meets a predetermined threshold.

9. The method of claim 8, wherein the nanotube array includes nanotubes arranged substantially perpendicular to the portion of the structure.

10. The method of claim 8, wherein the nanotube array is disposed on a carrier and the carrier is affixed to the portion of the structure.

11. The method of claim 8, wherein the laser ultrasound testing system is a low power fiber-based laser system.

12. The method of claim 8, further comprising dispersing heat generated by the laser ultrasound testing system on the structure with the nanotube array.

13. A non-destructive evaluation system comprising:

a nanoscopic structure generation module configured to generate an array of nanoscopic structures on a surface of a structure to be evaluated such that the array of nanoscopic structures has a predetermined directional orientation; and

an ultrasonic testing system configured to direct incident energy into the structure to be evaluated through the array of nanoscopic structures in a predetermined direction defined by the predetermined directional orientation of the array of nanoscopic structures.

14. The non-destructive evaluation system of claim 13, wherein the ultrasonic testing system comprises a laser ultrasound testing system.

15. The non-destructive evaluation system of claim 14, wherein the ultrasonic testing system comprises a low power fiber-based laser system.

16. The non-destructive evaluation system of claim 13, wherein the nanoscopic structure generation module is configured to generate the array of nanoscopic structures so that nanoscopic structures of the array of nanoscopic structures are arranged substantially perpendicular to the surface.

17. The non-destructive evaluation system of claim 13, wherein the array of nanoscopic structures comprises nanotubes.