Abstract
A single sided, air coupled ultrasonic NDT system based on the generation and reception of the a0 Lamb mode is described. 1–3 composite ultrasonic transducers are employed, transmitting and receiving transducers being oriented at the appropriate coincidence angle for the generation and detection of the mode; they are placed close together and scanned over the surface of the plate to produce a ‘C-scan’ image. Tests have been carried out on carbon fiber composite plates with delamination defects, the damaged areas being readily detected. The measurements have also been compared with numerical predictions based on a finite element model, good agreement being obtained.
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Castaings, M., Cawley, P., Farlow, R. et al. Single Sided Inspection of Composite Materials Using Air Coupled Ultrasound. Journal of Nondestructive Evaluation 17, 37–45 (1998). https://doi.org/10.1023/A:1022632513303
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DOI: https://doi.org/10.1023/A:1022632513303