Adhesively bonded composite repairs exhibit significant advantages in terms of mechanical efficiency compared to those achieved using mechanical fasteners. However they are sensitive to process parameter variations. In order to reliably use this patch repair, NDT assessments need to be performed. A European project COMPARE (SP1-JTI-CS-2010-01) funded under the Clean Sky program seeks to contribute via a comparative evaluation of three different NDT techniques: conventional ultrasound, laser ultrasound and laser shearography on carbon fibre reinforced polymer. The work being presented will show a comparison between conventional and laser ultrasound techniques, using samples with artificial delaminations. Conventional ultrasound used a pulsed echo method to detect delaminations and laser ultrasound interrogated sample via surface wave interaction delaminations. Laser ultrasound has the advantage over conventional ultrasound of being non-contact and has the potential for higher scanning speeds due to the larger coverage of surface wave. C-Scans were produced and compared using both methods. Additional analysis was performed in the time domain to help understand effects that the flaws have on the surface wave, which aided defect characterisation.
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