Measuring the Surface Residual Stresses in Shot Peened Steel Components by Magnetic Barkhausen Noise Method

摘要

Shot peening improves the fatigue life and resistance to stress-corrosion cracking of the engineering components by creating compressive residual stresses at the surface. Therefore, determination of residual stress state at the surface is very critical for service life of the industrial components. Due to high production rate and quality requirements, industry demands fast and non-destructive characterization methods for product controls. The magnetic Barkhausen noise (MBN) method may be an alternative to the existing residual stress measurement methods for ferromagnetic materials. This study aims non-destructive evaluation of surface residual stresses in the shot peened steels by MBN. Various sets of steel samples having different compressive residual stress state were prepared by systematic changing the several parameters of the shot peening process. The MBN measurements showed a clear relationship between surface residual stress state and the MBN emission.