Evaluation of the impact of geometry and plastic deformation on the stray magnetic field around the bone-shaped sample

Abstract

Influence of two factors: the variable cross-section and the localized plastic deformation, which affect the stray magnetic field profile of a ferromagnetic sample have been studied. Evaluation of an effect size is based on the analysis of the stray magnetic field component which is tangential to the longest dimension of a sample. However, in order to describe the nature of the stray magnetic field, the normal component(perpendicular to the tangential one and to the largest surface of a sample) was also measured.

It was found that the impact of the localized plastic deformation is qualitatively similar to the impact of the geometric narrowing. For the assessment one used a comparison of so called k coefficient that was determined as the absolute value of the derivative of the tangential component. Although some authors treat its distribution as information about residual stess distribution, the results indicate that a characteristic curve with two maxima stems from a cross-section reduction as well as plastic deformation presence.