The effect of stress and magnetic field orientation on surface Barkhausen noise in pipeline steel

Surface Barkhausen noise (SBN) measurements were made on a 2% Mn pipeline steel sample subjected to different levels of applied tensile and compressive isostress. The magnetic field direction was varied through a full 360 degrees . SBN voltage was found to depend on both stress level and magnetic field direction. The results were analyzed in terms of reorientation of magnetic moments from axial to circumferential directions with increasing tension. Compression was found to realign the magnetic moments in the axial direction.<
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