An Eddy Current Method for Flaw Characterization from Spatially Periodic Current Sheets
Early NDE research primarily focused on the ability to develop techniques which could detect flaws in structures. Eddy currents, induced by exciting coil probes placed over a structure, were found to be a valuable tool in detecting flaws in conducting materials. In recent years, efforts have been expanded from the detection of defects to a more quantitative characterization of flaws. In metallic structures, the important flaw characteristics consist of the flaw’s depth, position, size, shape, and material properties (flaw electrical conductivity, magnetic permeability etc.). This paper continues our efforts of the past two years to recover flaw characteristics from eddy current data.
KeywordsInverse Fourier Transform Integration Contour Harmonic Frequency Impedance Change Inversion Procedure
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