Recrystallization Behavior of Hot‐Rolled Microstructure with Texture Gradient and Texture of Final Sheet in Thin‐Gauge Electrical Steel

Abstract

The typical feature of hot‐rolled sheets exhibits strong inhomogeneity in microstructure and texture along the thickness direction, and the latter can be named as texture gradient. Herein, the recrystallization and grain growth behaviors of the hot‐rolled sheet in a thin‐gauge nonoriented electrical steel are investigated at different normalization temperatures. The origin and the growth behavior of the main recrystallization texture {114}<481> are revealed. The results show that the texture gradient in hot‐rolled sheets leads to the difference in microstructure and texture between the surface layer and the central layer after normalization. The strong {114}<481> recrystallization texture originates in the orientation transition zone and the vicinity of the grain boundaries of deformed α‐fiber grains in the central layer of hot‐rolled sheets. The volume advantage of {114}<481> grains stem from the favorable growth environment caused by the low‐deformation stored energy, low orientation gradient, higher mobility of grain boundary, and size advantage to their surrounding deformation structure. In the final sheet, {100}<021> texture is the most vital texture, but {114}<481> grains exhibit a large volume fraction. As there are only 4–5 grains on average along the thickness direction of the final sheet, the texture gradient along the thickness direction no longer exists.