Validation of Laser Shearography Testing for Fixed Foam Insulation Bonds

Electronic Laser Shearography is a relatively new Nondestructive Evaluation (NDE) technique that is used with excitation methods to measure differential displacements and subsequent strains at the surface of a material. Laser shearography was evaluated as an NDE technique for the inspection of adhesive bonds on fixed foam insulation for Atlas-Centaur cryogenic fuel tanks. A test program was conducted which evaluated the capability of electronic laser shearography to detect disbonds under field conditions on a full scale development test article. The test program validated laser shearography as a viable technique for the inspection of adhesive bonds in the test article configuration.