Selected Results of the Assessment of the Straightening Process of Steel Sheets Using the Barkhausen Noise Method

Abstract

The paper presents selected results of the assessment of straightening processes of steel sheets and plates in terms of monitoring changes in mechanical residual stresses. For the stress investigation, a method based on magnetic Barkhausen noise measurements was applied, and the custom measuring set-up was used. The study examined two different technological processes of leveling, based on tension for thin metal sheets and three-point overbending of thicker plates. The results are presented graphically in the form of directional diagrams of Barkhausen noise, as well as vectors representing orthogonal principal stresses in the cross-section plane. In general, an unfavorable stress state was observed on the opposite sides of the investigated sheets in the initial condition. The applied straightening operations resulted in a significant redistribution of residual stresses, in terms of both magnitude and sign.