Influence of Surface Properties on the Stress Magnetization Properties of Grain-oriented Silicon Steel

The influence of surface properties on the magnetic properties of grain-oriented silicon steel was investigated through measurements of iron losses and magnetic domain patterns in an oxide film-coated and mirror surface-finished specimen, with tensile stress applied in the rolling direction. When the surface roughness is reduced, the hysteresis loss falls rapidly, presumably because of the enhanced mobility of the domain wall. When the tensile stress is increased to about 10 MPa, the eddy current loss is reduced due to the refinement of magnetic domains, but above 10 MPa or so it gradually declines, presumably due to the rotation of the magnetization direction.