Intragranular orientation gradients play a critical role in deformation and recrystallization texture evolution of silicon steel. In this study, the dependence of intragranular orientation gradients on grain orientation in a cold-rolled Fe-3%Si alloy was systematically investigated through electron backscatter diffraction (EBSD), complemented by a rate-dependent crystal plasticity model, incorporating grain boundary resistance. A comparative assessment of intragranular orientation gradients in the grain core and grain boundary regions revealed that they are markedly sensitive to grain orientation, with the grain boundary region exhibiting a higher orientation gradient than the grain core. The formation of intragranular orientation gradients is governed by the orientation stability during plastic deformation: stable convergent α (//RD, rolling direction) and γ (//ND, normal direction) orientations develop lower orientation gradients, whereas grains with unstable divergent λ (//ND) orientations exhibit higher orientation gradients. Furthermore, intergranular interactions during rolling reduce orientation stability near grain boundaries, thereby promoting higher orientation gradients in the grain boundary region compared to the grain core.
Orientation rotation in grain-boundary regions plays a critical role in controlling the crystallographic texture of metallic materials. In this study, the ideal λ texture ({001}) in non-oriented silicon steel is chosen as the target orientation. The oriented stability in grain-boundary regions during cold rolling is systematically investigated by combining crystal plasticity simulations and quasi in situ electron backscatter diffraction (EBSD) experiments. Oriented stability is defined as the rate of change in the misorientation angle between an arbitrary orientation and the target orientation, thereby quantifying the rotational tendency relative to the target in grain-boundary regions. The results reveal that the oriented stability in grain-boundary regions is highly sensitive to both the initial and neighboring orientations. For initial orientations near the critical boundary separating convergence and divergence zones, the oriented stability is highly susceptible to neighboring orientations, with some neighboring orientations even reversing the rotation direction. In contrast, when the initial orientation is far from this critical boundary, the influence of neighboring orientations becomes weaker. Furthermore, the concept of contributed oriented stability is introduced to statistically evaluate the effect of different neighboring texture components in polycrystals. This work elucidates the underlying mechanism of orientation rotation in grain-boundary regions, and provides a new theoretical framework and a quantitative strategy for optimizing favorable textures.