Dependence of Hysteresis Loop on Stress in Non-oriented Electrical Steel Sheet

Abstract

What influences materials, exciting direction and flux density have on the dependence of a non-oriented (NO) electrical steel sheet on stress are discussed. The dependence on stress changes depending on flux density, because the magnetic mechanisms are domain-wall displacement at lower flux density and magnetization rotation at higher flux density. The magnetic properties of NO at low flux density are improved by tension, but deteriorated by compression because of the positive magnetostriction of easy axis ‹100›. Magnetizations are easy to rotate at high flux density. Then, those of NO, especially 50A1300, are deteriorated by tension in negative magnetostriction of hard axis ‹111›. The measured loop-width changes in the shape of a hysteresis loop due to compression which is attributed to hysteresis loss, and the effect of the steel surface in the high flux density region of the loop is reduced, and then hysteresis loss decreases. However, the loop widens with higher compression in the low-flux density region, where grain size mainly affects magnetic properties and its effect can be observed.