Abstract: This paper proposes a method to identify sub-surface defect
parameters in plates, using pulse-echo EMAT modes. First, the proposed method
deploys a reduced simulation model to efficiently reduce the computational cost
of EMAT forward analysis. Then, an approach of signal processing based on peak
values at back-wall echo and POD method applied to extracted feature of EMAT
signal are introduced. Finally, inverse analysis based on reduced POD basics is
applied for defect parameters identification. Promising experimental results
with high accuracy on both simulation and synthetic measurement data
demonstrate the capability and effectiveness of the proposed method. The
extension of this method can be applied in pipe inspection for defect
characterization.
