Trends in the development of grain‐oriented electrical sheet

Abstract

Thin gauge, high silicon content, perfect crystal orientation and small domain wall spacings are the fundamental features of an ideal electrical steel sheet with minimum core loss and maximum polarization. For achieving these properties in the fabrication process, very exact control of secondary recrystalliration is necessary, which becomes more and more difficult with decreasing sheet thickness and increasing silicon content. In the present paper the influence of the starting conditions – i.e. the primary recrystallized grain structure and precipitation distribution – on selective grain growth and Goss‐texture formation is described. For RGO and HGO typical differences in the primary grain size, critical inhibitor diameter and amount of primary Goss‐grains have been observed. By increasing the knowledge about the physics of electrical steel sheet, the fabrication process and magnetic properties have been continuously improved in the past. Today, new techniques of strip production like thin strip casting are an important aspect for further development offering very promising perspectives on new possibilities of texture control.