Residual Stress Analysis in Nonoriented Electrical Steel Sheets by Barkhausen Noise Measurements

The nondestructive magnetic Barkhausen noise (MBN) technique has been used to study the effect of residual stress in nonoriented electrical steels. The MBN response is presented and evaluated with respect to thermomechanical treatments. The ensuing microstructure was studied using scanning electron microscopy, transmission electron microscopy, and hardness measurements. The stress-dependent MBN measurements exhibit good correlation with XRD stress measurements made by the d - sin 2 ψ method, using Cr-Ka radiation, and (211) reflections. It has been found that there is a good correlation between MBN response and variations in microstructure, which affects mechanical properties.