Characterization of magnetic field rotation of steel sheet under uniaxial stress

The rotation of magnetic field strength on a steel plate caused by uniaxial stress has been known for years. However, previous study investigated this phenomenon rather experimentally using hall plates and searching coils. This paper presents a fundamental study of magnetic anisotropy based on an analytic model using magnetic scalar potential. The magnetic field strength of the steel sheet can be solved mathematically by performing a special coordinate transformation. The calculated angular displacement due to stress induced magnetic anisotropy was later found to be highly consistent with FEM simulation results. Finally, the quantization of magnetic field rotation of an electrical sheet (ES) under variable tension stress was performed. Using 50CS470 ES sheet as the testing sample, it was discovered the rotation as much as 25° occurred when 50 MPa tension load was applied, corresponding to a permeability ratio of 2.8.