NONDESTRUCTIVE TESTING OF COMPOSITE AIRCRAFT STRUCTURES WITH INFRARED AND SHEAROGRAPHIC IMAGING TECHNOLOGIES

The increased use of advanced composite materials for primary aircraft structures and blading has placed new and difficult demands on the traditional methods of nondestructive testing, from both the productivity and maintainability standpoints. Two new technologies, electronic shearography and thermal/microwave coupled infrared imaging, offer dramatic increases in testing throughput and sensitivity to defects in materials and structures. Electronic shearography has a proven application in the detection of unbonds, crushed core, impact damage, and delamination in composites, honeycomb, and foam-cored structures. Corrosion in aluminum honeycomb is easily detected. Thermal/microwave coupled infrared imaging can easily detect delaminations and entrapped moisture. The paper will provide a background to these new technologies and discuss field tests.