A NEW NDE CAPABILITYFOR THIN-SHELLED STRUCTURES

A POWERFUL, NOW IMAGING MODALITY IDEALLY SUITED FOR THIN-SHELLED STRUCTURES BUT CONSIDERABLY MORE GENERAL IN NATURE IS PROPOSED. THE APPROACH IS BASED ON WELL- ESTABLISHED DIGITAL TOMOSYNTHESIS PRINCIPLES AND MODERN REAL-TIME DIGITAL RADIOGRAPHY TECHNIQUES. A SERIES OF COMPONENT RADIOGRAPHS OF A STRUCTURE TAKEN FROM DIFFERENCE ANGLES ARE MANIPULATED ACCORDING TO A RESTORATIVE ALGORITHM TO RECOVER A SET OF IMAGES OF PARALLEL SURFACE WITHIN THE OBJECT. THE METHOD IS COMPLEMENTARY TO COMPUTED TOMOGRAPHY (CT); BUT WHEREAS CT PRODUCES IMAGES OF PLANAR SURFACES SURFACES PARALLEL TO THE DIRECTION OF THE X-RAY FLUX, THE PROPOSED APPROACH PRODUCES IMAGES OF ARBITRARY CURVTILLINEAR SURFACES NORMAL TO THE X-RAY FLUX. CONSEQUENTLY, THE PROPOSED INSTRUCMENT, WHICH HAS BEEN DESIGNATED A DIGITAL TOMOGRAPH (DT), IS SUPERBLY TAILORED FOR NON-DESTRUCTIVELY EVALUATING STRUCTURES WHICH ARE FABRICATED IN A LAMINA OR MULTILAYE FASHION. THE ABILITY TO IMAGE TOMOGAPHIC SURFACES WITHIN AND CONCENTIC TO THE NATURAL SHAPE OF THE OBJECT PROVIDES A SUPERIOR INSPECTION CAPABILITY THAT CANNOT CURRENTLY BE MATCHED BY ANY OTHER NDE METHOD, INCLUDING CT.