MAGNETIC-PROPERTIES AND DYNAMIC DOMAIN BEHAVIOR IN GRAIN-ORIENTED 3-PERCENT SI-FE

The magnetic properties of soft magnetic materials are based on dynami c behavior of magnetic domain walls. Many domain structure studies hav e contributed to the progress of magnetic materials. In this paper, th e present state of new development in advanced grain-oriented silicon steel is introduced through the aid of dynamic domain observation of r eal materials with forsterite film. The basic magnetic phenomena of ma terial, such as the dynamic behavior of surface closure domains, domai n wall pinning, and domain structure under rotating magnetization, are explained mainly through the observation of static and dynamic domain wall movements under a high-voltage scanning electron microscope. A f ew techniques for manufacturing the latest grain-oriented silicon stee l, such as improvement in alignment with (110) [001] orientation, incr ease in the number of mobile domain walls, and relaxation of domain wa ll pinning, are also described through the observation of dynamic doma in patterns. Examples of core losses are given for ideal grain-oriente d silicon steel as industrial material, and future developments are pr edicted.