On the sensitivity of corrosion and fatigue damage detection using guided ultrasonic waves

Constant, long-time monitoring of large plate-like structures, e.g., oil storage tanks, can be performed using permanently attached remote sensors. A guided ultrasonic wave array consisting of piezoelectric transducer elements for the excitation and reception of the first antisymmetric Lamb wave mode A0, has been designed and built. Laboratory measurements for a steel plate containing various defects have been performed. The results are compared to theoretical predictions and the sensitivity of the array device for defect detection is ascertained.