Eddy current testing of cracks using multi-frequency and noise excitation

Eddy current testing (ECT) methods are widely used to inspect non-ferromagnetic metallic materials. However, the characterization of a crack is not easy to obtain, and for this purpose, other eddy current evaluation methods are still under investigation. In this paper, a non-conventional excitation method with white noise was tested to detect surface and sub-surface cracks in aluminum plates and the performance of the method was compared with the multi-frequency excitation method. The generation of the excitation signals, the experimental setup, and the scanning tests were explained in detail.

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