Experimental Determination of Critical Fields of 90-Degree Domain Wall Displacement in Plastically Deformed Low-Carbon Steels

Experimental data are presented for the field dependences of differential magnetic permeability μd (H0) of plastically deformed low-carbon steel-St3 samples both in an unloaded state and under tensile stresses. It is shown that applying tensile stresses drastically changes the shape of curves μd (H0 ) a fact that indicates compensation of internal residual compressive stresses in the samples by external tensile stresses. A new technique is proposed for the experimental determination of the critical fields of displacement of 90-degree domain boundaries based on dependences μd (H0 ). Residual compressive stresses in plastically deformed St3 steel are estimated.