Crack shape reconstruction using ECT camera system

An ECT (eddy current testing) camera system is proposed to quantitatively evaluate/visualize cracks of the metal structures. It is composed of the multi-coil ECT probe, ECT instrument, and computer-aided analysis/visualization that correspond to the lens, film and development/picture in the elements of photography, respectively. At first, scanning the probe in one direction gives ECT signals as a two-dimensional image. Second, a method of the image processing narrows to visualize crack shapes. Finally, an inversion based on the finite elements evaluates the depth of cracks. It is applied to inspection of an austenite stainless steel plates with fatigue cracks so as to discuss the accuracy of the system.