The Significance of Microstructure and Texture on Magnetic Properties of Non‐Oriented Silicon Steel: Strip Casting versus Conventional Process

Abstract

High‐performance nonoriented silicon steel can be produced by the novel strip casting process with a microstructure necessary for magnetic properties. In this regard, the significance of microstructure and texture on magnetic properties of nonoriented silicon steel are comparatively studied in strip‐casting process and conventional hot‐rolling process. The as‐cast strips are uniquely composed of fine equiaxed grains and coarse {100} columnar grains, whereas the hot‐rolled sheets are characterized by fine and uniform microstructure with random orientation. After cold rolling and recrystallization annealing, unfavorable {111} texture dominates the recrystallization texture in the conventional process because of compatible deformation effect of high density of grain boundaries. In contrast, coarse grain with pronounced {100} texture of annealed sheet is obtained via strip‐casting process, which is attributed to strong shear deformation and retention of {100} texture. Considering the synergistic benefits of texture and grain size, nonoriented silicon steel produced by strip casting exhibits superior magnetic properties with low magnetic anisotropy. The magnetic induction of nonoriented silicon steel produced by strip casting is intriguingly 0.06 T higher and the core loss is 0.4 W kg−1 lower than the conventional process. The current study provides practical guidance for processing of nonoriented silicon steel.