Dual-frequency ECT NDT measurements by flat shape probe

A flat shape eddy current probe has been developed in order to increase the excitation depth into the investigated material via decreasing the effective distance between the sample and the probe, and in order to reduce the fabrication complexity. The fiat shape probe geometry can be effectively utilized in the case of common inductive type sensors as well as in the case of more refined fluxgate / fluxset detectors, however, it does not have to have a ferromagnetic core. In the presented work a flat shape probe was used in dual-frequency eddy current non-destructive measurement mode.