Real-Time Super-Resolution Signal Processing Applied to the Ultrasonic Imaging of Adhesively Bonded Joints

The increased use of composite materials and adhesive bonding technology in the aerospace industry has increased the demand for techniques and instrumentation capable of detecting the characteristic flaws in these materials. An important class of flaws includes delaminations in composite materials and disbonds in adhesively bonded joints. These flaws may be detected using ultrasonic inspection techniques, however, in many instances the component to be inspected may only be accessed from one side, thereby requiring the use of pulse-echo ultrasonics. Using conventional techniques, delaminations are usually detected by selecting a known reflection, for instance the back surface echo, to produce a C-scan image. In order to adequately determine the criticality of a delamination, however, the depth of the flaw within the laminate must also be accurately determined.[1] This may be accomplished by sequentially acquiring and processing amplitude data that contain the front and back surface echoe