Results of magnetometry data processing for non-destructive testing of compressive mechanical stress levels in steels

Abstract

We plotted the fields of measurement coil signal as functions inversely proportional to reversible magnetisation in low-carbon St20 steel plates subjected to plastic tensile strain. Performing an additional approximation of our experimental data using three pseudo-Voigt functions allowed us to detect the information concerning irreversible motion of the 90-degree domain walls that are most sensitive to mechanical stresses. As a result of performing mathematical processing of experimental data we managed to improve validity of estimating the fields of stress-induced magnetic anisotropy and mechanical stresses.