American Institute of Physics
TNO Industrie en Techniek
|Source:||Review of Progress in Quantitative Nondestructive Evaluation, 20-25 July, 2008, Chicago, IL, USA, 1096, 727-734|
|AIP Conference Proceedings|
Electronics · Corrosion monitoring · Dispersion · Guided wave · Inversion · Parameterization · Tomography · Travel time · Ultrasonic
Guided wave tomography is a promising technique for the monitoring of corrosion over large areas. Guided waves have a wave speed mat depends in certain frequency-thickness regimes on the local thickness of the waveguide they follow. Therefore, the travel time of the guided wave over a fixed distance contains information about the thickness profile along its path. By measuring the travel time over multiple paths in such a way that the complete waveguide is covered and applying tomographic inversion to the measured values, a thickness profile of the waveguide can be recovered. Two challenges of guided wave tomography are compensation for dispersion and parameterization of the surface of the waveguide. Removing the strong dispersive behavior is essential to accurately determine the travel times. Smart parameterization is needed to obtain accurate, high-resolution thickness profiles. This paper demonstrates the application of guided wave tomography on plates and pipes and discusses several methods for dispersion removal and parameterization. © 2009 American Institute of Physics.