IN LARGEBONDED STRUCTRUES

FOR NONDESTRUCTIVE EVALUATION TO REMAIN A VERSATILE TOOL, NOT LIMITED BY COMPLEX GEOMETRIES OR MATERIAL TYPES, INDUSTRY MUST REFINE THE EXISTING NONDESTRUCTIVE EVALUATION TECHNIQUES OR DEVELOP NEWER ONES. BECAUSE OF THE RECENT ADVANCES IN HIGHER SENSITIVITY INFRARED DETECTORS, THE AVAILABILITY OF A WIDER SPECTRUM OF OPTICAL MATERIALS, IMPROVEMENTS INFILTERING AND DATA PROCESSING TECHNIQUES, AND THE DEVELOPMENT OF LOWER NOISE AMPLIFIERS AND ELECTRONICS,INFRARED RADIOMETRY MAY BE AN ALTERNATE TECHNIQUE TO EVALUATE BONDING INTEGRITY. SINCE THE ANALYSIS IS BASED UPON THE THERMAL GRADIENTS ESTABLISHED AT A MATERIAL INHOMOGENEITY, THE THERMAL GRADIENTS MAY BE EASILY RESOLVED IN THE INFRARED REGION OF THE ELECTROMAGNETIC SPECTRUM THROUGH A VISUAL INSPECTION OF ISOTHERMS. THIS PROPOSED EFFORT WILL DEFINE A MINIMUM VOID SIZE AND MAXIMUM VOID DEPTH WHICH WILL PRODUCE A DETECTABLE AND CONTRASTING THERMAL SIGNATURE; WILL PARAMETRICALLY EVALUATE ISOTHERM FORMATION TO IDENTIFY AND DEFINE OPERATIONAL PARAMETERS FOR PHYSICAL TESTING; WILL STUDY ISOTHERM DISTORTION AS A FUNCTION OF VOID SIZE, SHAPE, AND DEPTH; AND FINALLY, WILL CHARACTERIZE APPLICABLE INFRARED DETECTORS FOR PHASE II TESTING. THESE TOPICS WILL BE REVIEWED TO ESTABLISH THE FEASIBILITY OF APPLYINGINFRARED RADIOMETRY TO CHARACTERISTIC BOUNDING INTEGRITY.