Grain Orientation Selection Behavior at Various Stages and Secondary Recrystallization Growth Mechanism of Grain‐Oriented Pure Iron

This study designed the chemical composition of grain‐oriented pure iron (GOPI) using Thermo‐Calc and fabricated the material via smelting, forging, hot rolling, cold rolling, and subsequent primary and secondary recrystallization annealing. The microstructure, texture, precipitation behavior, and magnetic properties at each stage were characterized by SEM, TEM, EBSD, XRD, and NIM‐2000E silicon steel magnetic property measuring instrument. The results show that the hot‐rolled sheet exhibits a texture gradient, where the central grains are dominated by {114}<481>, rotated cube {001}<110>, and the α‐fiber texture spanning {112}<110> to {117}<110>. After normalization, the γ‐fiber within the matrix becomes continuous, and the α‐fiber texture is retained with {112}<110> to {116}<110> as the dominant components. During cold rolling at high strain levels, the texture rotates along two distinct paths toward pronounced {111}<110> and {223}<110> orientations. The favorable texture gradient established at this stage enables the SR‐1 880 °C ( B _s  = 1.98 T) to achieve the optimum performance during secondary recrystallization, with ∼30% Goss texture and 15.7% {114}<481> retained in the matrix. Moreover, in conjunction with Thermo‐Calc phase‐diagram predictions and annealing‐microstructure analyses, the secondary recrystallization behavior was governed primarily by the α → γ phase transformation, whereas grain growth exhibited pronounced spatial heterogeneity.