Use of Barkhausen Noise in Fatigue

Barkhausen noise is generated by abrupt changes in the magnetization of materials under applied AC magnetizing field /1/. These changes are known to be affected by residual and/or applied stresses /2, 3/. Monitoring the Barkhausen noise under controlled conditions then provides a means of evaluating the stress state of the material /4/. The relation between stress and Barkhausen noise level is illustrated in Figure 1: the lower the compressive stress or the higher the tensile stress, the higher the Barkhausen noise level