Interpretation of Magnetic Barkhausen Noise Bursts in Low Frequency Measurements

Experimental results allow the identification of three main magnetic Barkhausen noise bursts, each occurring at a different applied field. Magnetostrictive effects can be related to the 1st and 3rd bursts, because closure domain walls are created and/or eliminated. The 2nd burst occurs at the coercive field and it is usually the most intense, and is attributed to domain wall movement. The analysis of the three main bursts gives an important insight on how stress may affect the losses and magnetic Barkhausen noise. A brief review is also presented about the magnetic Barkhausen noise technique.