Adaptive Testing of Ferromagnetic Materials Utilizing Barkhausen Noise

A new method of the Barkhausen noise measurement and optimization of the measured data processing with respect to non-destructive evaluation of ferromagnetic materials is proposed. The measuring method is based on well-known method of magnetic adaptive testing where a complex set of minor hysteresis loops is measured. Collecting the sets of obtained Barkhausen noise envelopes into suitable designed matrices and optimizing the data processing with respect to the maximum sensitivity to the evaluated variable were developed. The method is illustrated on the evaluation of plastic deformation of a steel sample. It is shown that the proposed measuring method and measured data processing bring an improvement of the sensitivity to the evaluated variable when comparing with measuring the traditional Barkhausen noise parameter (root mean square).