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This work proposes the utilization of the phase information from the response signal of an eddy current transducer with orthogonal coils in order to get an enlarged image of carbon fibers from a graphite-epoxy composite type [−45 2 0 ,+45 2 0 ] S and [−45 2 0 ,0 2 0 +45 2 0 ] S consisting of 24 fiber layers. A 2D Fourier transform was then applied to the phase signal, which is propagated backward by means of an operator that represents the solution of a Helmholtz equation. The image can be focused on a fiber layer choosing an adequate phase multiplication constant. With the view to obtain a clear-cut fiber contour, a Canning optimal regularizing algorithm was used. By choosing another phase multiplication constant the image can be focused on another fiber layer.

This work presents a new type of eddy-current sensor used in non-destructive evaluation, being able to detect with equal sensitivity both long and short flaws, in any orientation. The proposed sensor is of send–receive encircling type, using for the control operation a rotating magnetic field.

This work presents a magnetic sensor designed to determine the fatigue level in parts made of ferromagnetic steels using the incremental magnetic permeability method.

The work presents a method for the quantitative evaluation of the shape and severity of discontinuities by processing the signal delivered by the sensor with orthogonal coils. Unlike other sensors used by now to this end, the sensor we propose presents the advantage of a more exact localization of the discontinuity and an increased resolution.

The automatic systems for eddy current non-destructive control permit rendering evident superficial discontinuities in the electroconductive products. Their response is influenced by numerous factors and therefore it is quite difficult to quantitatively estimate the shape and severity of the detected discontinuity, based on the sensor's response. This work presents an artificial intelligence system based on fuzzy logic, dedicated to the quantitative evaluation of the severity of material discontinuities existing on wires, which dramatically reduces noise influence and enables to determine the discontinuity depth as a function of prescribed quality classes.