Investigation of magnetic response to plastic deformation of low-carbon steel

In this work results of magnetic investigation of structure degradation of low-carbon steel due to plastic tensile strain are presented. Two series of magnetically closed window-shaped and open strip-shaped specimens were deformed to different strains up to 20% and measured after unloading. Magnetic hysteresis and Barkhausen noise measurements were done with magnetization parallel to the strain direction. Two-peak profiles of differential permeability and Barkhausen noise envelope were found and explained by splitting of the domain wall motion into two stages due to residual intrinsic stresses. Influence of generated dislocation tangles on magnetization process is also considered.