Feasibility of nonlinear acoustic technique with ultrasonic guided waves for nondestructive defect evaluation

Feasibility of nonlinear acoustic modulation technique [K. I. Jung and S. W. Yoon, Proceedings of Internoise 2000, Nice, France, p. 205 (2000)] was discussed for nondestructive defect evaluation. Such nonlinear acoustic technique can be applied to localize a defect in a solid rod and also extended to layer‐structured media. In this study, nonlinear acoustic technique with ultrasonic guided waves is introduced. Nonlinear acoustic responses from a defect are observed with guided waves in a 2‐D structure. The defect was oriented in the direction of guided wave propagation. The experimental results show that the nonlinear acoustic technique with ultrasonic guided waves seems feasible for nondestructive evaluation of 2‐D structure. [Work supported by BK21 Program in Korea and by the Basic Research Program of KOSEF (R01‐2000‐000‐00014‐0).]