Laser ultrasonic inspection of honeycomb aircraft structures
Ultrasonic methods have been used extensively for the inspection of advanced composite materials and adhesively bonded structures. Conventional ultrasonic inspections usually require couplants to propagate ultrasonic waves to and from the part surface. Delaminations, porosities, and foreign inclusions in composite laminates can be successfully detected by pulsed-echo and through-transmission modes of ultrasonic inspection. Debonds in adhesively bonded structures are most effectively detected by the through-transmission mode of ultrasonic inspection.