Magnetic Barkhausen emission to evaluate fatigue damage in a low carbon structural steel

The various stages of fatigue damage in low carbon structural steel have been characterized using magnetic Barkhausen emission (MBE) signal analysis technique during high cycle fatiguing. The observed trends in the variation in MBE peak voltage showed an initial increase followed by a decrease. After that a sharp increase was found during online monitoring of fatigue till failure. The variation of MBE peak voltage with mechanical deformation was correlated with the microstructural changes at different stages of fatigue damage. The state-of-the-art of microstructural changes at various stages of fatigue damage has been established using transmission electron microscopy (TEM) to correlate the changes in the magnetic Barkhausen parameters with the microstructural changes.