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In this paper, a transducer allowing nondestructive evaluation of material state in various directions is presented. The axial-symmetry transducer is using a matrix of vector magnetic field sensors. Each sensor is utilized for the observation of three orthogonal components. First, the construction is shown and the general performance is evaluated. Then, the data processing and integration algorithm for reconstruction of the signals is presented. Finally, the operation of the transducer is verified using a low-carbon steel plate having notches of different depths and aligned at various angles to the scanning axis. The results are presented and discussed.

An effective method for inspection of billets made of titanium alloy is proposed. Two nondestructive testing (NDT) techniques were utilized: phase array ultrasonic testing (PA) and eddy current testing (ECT). In this paper, results obtained by ECT method will be shown and discussed. A dedicated transducer was introduced and optimized. The results of numerical simulations as well as measurements will be shown and discussed.

In this paper, stress- and fatigue-loaded ferromagnetic steel samples were evaluated using three different remanent flux leakage transducers. Giant magnetoresistive sensors were used as the pickup elements. Each transducer has its own integrated local magnetizing section, which allows us to magnetize the tested material in different directions. The defect detection dependency on angle, at which it occurs to the magnetizing field and sensing element, is minimized by gathering and then integrating the information from transducers. The performance of the transducers was verified using a steel plate (S355J2G3) with electro-discharge machined notches. Further experiments were carried out using fatigue- and stress-loaded steel samples.

The magnetic leakage flux, multifrequency eddy current and Barkhausen noise methods were used to evaluate changes in materials properties induced by stress. Seven samples made of ferromagnetic low carbon steel with different stress level were prepared. The results showed tensile deformed samples at room temperature with a yield at around 350 MPa, residual strain between 0.7% and 14% and tensile stress from 100 MPa to 389 MPa.