$\left\{ {114} \right\} \langle 4\overline{8} 1\rangle$ Annealing texture in twin-roll casting non-oriented 6.5 wt% Si electrical steel

Abstract

Twin-roll casting was adopted to fabricate a 2.7-mm-thick material of the non-oriented 6.5 wt% Si electrical steel, which was then hot rolled, warm rolled, and annealed. A detailed study of the microstructural and textural evolutions in the whole processing route was conducted by optical microscopy, X-ray diffraction, and electron backscattered diffraction. Beneficial λ-fiber texture, strong $\left\{ {114} \right\} \langle 4\overline{8} 1\rangle,$ and Goss textures dominated the annealing texture. Special attention was focused on the origin and evolution of the $\left\{ {114} \right\} \langle 4\overline{8} 1\rangle$ texture during the annealing process. The results showed that the nucleation sites of the $\left\{ {114} \right\} \langle 4\overline{8} 1\rangle$ nuclei were not only confined to deformation bands of the deformed $\left\{ {001} \right\} \langle 1\overline{1} 0\rangle$ grain but also widely distributed in many other deformation heterogeneities of the warm-rolled sheet. The high similarities demonstrated by the nucleation and recrystallization textures, and the gradually intensified $\left\{ {114} \right\} \langle 4\overline{8} 1\rangle$ recrystallization texture indicated the combined operations of the oriented nucleation and oriented growth mechanisms during the evolution of the $\left\{ {114} \right\} \langle 4\overline{8} 1\rangle$ recrystallization texture. After recrystallization, some $\left\{ {114} \right\} \langle 4\overline{8} 1\rangle$ grains which already acquired the advantage in grain size over those clustered $\left\{ {111} \right\} \langle 1\overline{2} 1\rangle$ grains due to the orientation pinning effect tended to gain further growth during the grain growing stage, resulting in the prevalence of the $\left\{ {114} \right\} \langle 4\overline{8} 1\rangle$ annealing texture.