Domain wall characterization inside grain and around grain boundary under tensile stress

Stress measurement is an important field of non-destructive testing and evaluation (NDT&E). This can ensure stability and structural rigidity of workpieces. The challenging task of stress measurement is the properties characterization of the microscopic magnetic, especially the microstructure at different location of grains. The qualitative analysis of magnetic properties variation under low stress inside grain and around grain boundary are difficult to be obtained with a reliable solution. This paper investigates characters of the domain wall inside grains and around grain boundaries under low tensile stress. The domain walls of the silicon steel sheet are captured by the magneto-optical Kerr effect (MOKE) microscopy. The stress changes the magneto-elastic energy and the angle between magnetization and stress. The relationship among domain wall, magneto-elastic energy, the magnetization inside grains and around grains boundaries under different tensile stress is provided and analyzed in details. Magnetization work calculates the energy required for magnetization to quantify the difference of the magnetic domains distribution caused by increment of magneto-elastic energy under different tensile stress in different locations. The difference of magnetization work in these locations is highly affected by the tensile stress. This proposed work has the potential to evaluate the effect of grain and grain boundary on stress measurement.