Recrystallization of a 2.8 wt% Si Non-oriented Electrical Steel After Skew Cold Rolling at Different Angles to the Hot Rolling Direction

The magnetic properties of non-oriented electrical steelNon-oriented electrical steel (NOES) are closely related to the final microstructureMicrostructure and textureTexture of the annealed sheets, which not only depend on the annealing parameters, but also on the prior thermomechanical processing procedures applied to the steelSteel before annealing. The cold deformation immediately before annealing generates an energized and inhomogeneous materialMaterials state that is critical to the subsequent recrystallizationRecrystallization since the nucleation and grain growth are all affected by the microstructureMicrostructure/substructure, textureTexture, and the strain energy generated during the deformation processProcess. Conventional cold rolling is a plane-strain compression processProcess (2D), which normally produces very similar deformation and final annealing texturesTexture, i.e., the <110>//RD (rolling direction) and <111>//ND (normal direction) fibers, which are not the desired orientations for good magnetic properties. In this study, skew cold rolling is employed to processProcess non-oriented electrical steelNon-oriented electrical steel, in which the hot-rolled steelSteel plates are fed into the rolls at different angles (22.5° and 45°) from the conventional rolling direction. This rolling scheme generates a unique three-dimensional (3D) deformation mode that can significantly alter the cold rolling textureTexture, which in turn, leadsLead to different recrystallizationRecrystallization textureTexture. A 2.8 wt% Si non-oriented electrical steelNon-oriented electrical steel is skew cold rolled and the recrystallizationRecrystallization of the steelSteel is investigated by annealing the sheets at 1050 °C for different times (30 s and 60 s) to capture both partial and complete recrystallizationRecrystallization. The results are compared to those after conventional rolling and cross rolling. It is shown that skew rollingSkew rolling can significantly enhance the <001>//ND textureTexture (desired for good magnetic properties) and largely reduce or eliminate the detrimental <111>//ND textureTexture.