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Herein, four kinds of initial Goss textures with different deviation angles (0°, 5°, 10°, and 15°) are obtained by controlling the included angles between the longitudinal directions of rectangular cutting specimens and the initial rolling direction of the raw material. Then, 0.05 mm thick grain‐oriented silicon steels are fabricated by cold rolling and primary recrystallization annealing. Effects of initial textures on the microstructure and texture evolutions and magnetic properties are investigated in detail. Compared with sharp {111}<112> in the cold rolling sheet with initial exact Goss, the deviated Goss favors the formation of strong {111}<112> + weak {h11}<1/h 1 2> textures. After annealing, sharp {210}<001> + medium {110}<001> textures develop as a result of the small initial deviation, while larger initial deviations contribute to the {310}<001> texture. In addition, the average grain sizes are also related to recrystallization textures. Consequently, the distinct recrystallization microstructures and textures result in the differences of magnetic properties. [ABSTRACT FROM AUTHOR]

0.05–0.15 mm-thick ultra-thin grain-oriented silicon steel sheets were successfully produced by a novel processing route including strip casting, hot rolling, normalizing, two-stage cold rolling with intermediate annealing, primary recrystallization annealing and secondary recrystallization annealing. The evolutions of microstructure, texture and inhibitor along the processing were briefly investigated. The results showed that the initial Goss orientation originated due to the heterogenous nucleation of δ-ferrite grains during solidification. Because of the lack of shear deformation, only a few Goss grains were observed in the hot rolled sheet. After the first cold rolling and intermediate annealing, Goss texture was enhanced and distributed in the whole thickness. A small number of Goss grains having a high fraction of high energy boundaries exhibited in the primary recrystallization annealed sheet. A large number of fine and dispersed MnS and AlN and a few co-precipitates MnS and AlN with the size range of 10–70 nm were also observed. Interestingly, a well-developed secondary recrystallization microstructure characterized by 10–60 mm grains and a sharp Goss texture were finally produced in the 0.05–0.15 mm-thick ultra-thin sheets. A magnetic induction B 8 of 1.72–1.84 T was obtained. Another new finding was that a few {2 3 0}〈0 0 1〉 and {2 1 0}〈1 2 7〉 grains also can grow up abnormally because of the high fraction of high energy boundaries and the size and number advantage, respectively. These non-Goss grains finally deteriorated the magnetic properties of the ultra-thin sheets. In addition, low surface energies of {hk0} planes may also contribute to the abnormal growth of Goss, {2 3 0}〈0 0 1〉 and {2 1 0}〈1 2 7〉 grains. [ABSTRACT FROM AUTHOR]

• Low-finishing-temperature hot rolling and batch annealing result in large grains. • Prior large grains lead to desirable recrystallization microstructure and texture. • A potential processing method to improve magnetic properties is proposed. The grain size prior to cold rolling plays an important role in the microstructural, textural evolution and magnetic properties of non-oriented silicon steel sheets. In this work, we proposed a new way to obtain large grain size before cold rolling and applied it to a 1.0 wt% Si-0.2 wt% Al non-oriented silicon steel, i.e., appropriate low-finishing-temperature hot rolling combined with batch annealing. The grain growth process during batch annealing was investigated using a quasi in-situ electron backscattered diffraction (EBSD) technique. It was demonstrated that significant grain growth took place through a strain-induced boundary migration mechanism. Then a large number of in-grain shear bands were formed in the cold rolled microstructure and could provide nucleation sites for Goss ({1 1 0} 〈0 0 1〉) and λ-fiber (〈0 0 1〉//ND) recrystallized grains, thus resulting in a coarse-grained and homogeneous recrystallization microstructure with weakened γ-fiber (〈1 1 1〉//ND) texture, strengthened Goss and λ-fiber texture. Consequently, superior magnetic properties (B 50 = 1.763 T, P 1.5/50 = 4.30 W/kg) were obtained. For comparison, the conventional processing route without batch annealing was also investigated. A small-grained and inhomogeneous recrystallization microstructure with pronounced γ-fiber texture was produced in the finally annealed sheet, which could significantly deteriorate both the magnetic induction and iron loss. This work provided a new way to enlarge the grains in hot rolled sheets by low temperature batch annealing instead of the conventional high temperature normalization. Thus a new processing route to fabricate low silicon non-oriented electrical steels with high permeability and low iron loss was established. [ABSTRACT FROM AUTHOR]

• Ultra-thin sheets were produced based on primary recrystallization. • Dependence of texture evolution on initial Goss orientation was clarified. • Different cold rolled and recrystallization textures evolved in Hi-B and CGO. • Mechanism of recrystallization of typical texture was investigated. • Relationships of iron loss upon grain size, texture and thickness were clarified. Based on cold rolling and primary recrystallization method, 0.05–0.15 mm-thick ultra-thin grain-oriented silicon steel sheets were successfully produced by utilizing the high induction (Hi-B) and common grain-oriented (CGO) silicon steels as raw materials, respectively. Thus, the effects of sharpness of initial Goss texture on the evolutions of microstructure, texture and magnetic property were investigated in detail. For Hi-B steel, 'smooth' microstructures were formed in the cold-rolled sheets, and the textures evolved along the following path: exact {1 1 0}〈0 0 1〉 → {2 3 0}〈0 0 1〉 → {1 1 1}〈1 1 2〉. By contrast, significant deformation bands or shear bands were observed in the CGO steel, and the textures developed along the following path: deviated {1 1 0}〈0 0 1〉 → {2 1 0}〈0 0 1〉 → {1 1 1}〈1 1 2〉. After annealing, inhomogeneous microstructures containing some clusters with large grains (∼2–4 mm) and fine equiaxed grains appeared in the Hi-B steel and the associated texture evolution with increasing cold rolling reduction followed the path: {1 1 0}〈0 0 1〉 → {2 3 0}〈0 0 1〉 → {2 1 0}〈0 0 1〉. Unlike the Hi-B steel, relatively fine and uniform equiaxed recrystallization grains were produced in the final CGO steel, and the texture evolved along the route: {2 1 0}〈0 0 1〉 → {6 1 0}〈0 0 1〉. Consequently, further research focusing on the recrystallization mechanism was studied. The results showed that {1 1 0}〈0 0 1〉 and {2 1 0}〈0 0 1〉 developed into the predominated components due to oriented growth and oriented nucleation respectively in the 0.05 mm-thick Hi-B sheet, while {1 0 0}〈0 0 1〉 became the main texture with the aid of oriented nucleation advantage in the CGO sheet. In addition, more attention was paid on the magnetic properties of the ultra-thin sheets, and the results showed that heavy cold rolling reduction as well as low annealing temperature contributed to better magnetic induction. Furthermore, the separated iron loss components were obtained to clarify the relationships between the iron loss and grain size, texture and thickness. [ABSTRACT FROM AUTHOR]

A 0.1 mm-thick grain-oriented silicon steel sheet was successfully produced using strip casting and three-stage cold rolling method. The microstructure, texture and inhibitor evolution during the processing was briefly analyzed. It was found that Goss texture was absent in the hot rolled sheet because of the lack of shear deformation. After normalizing, a large number of dispersed MnS precipitates with the size range of 15–90 nm were produced. During first cold rolling, dense shear bands were generated in the deformed ferrite grains, resulting in the intense Goss texture after first intermediate annealing. The microstructure was further refined and homogenized during the subsequent cold rolling and annealing processes. After primary recrystallization annealing, a homogeneous microstructure consisting of fine and equiaxed grains was produced while the associated texture was characterized by a strong γ-fiber texture. Finally, a complete secondary recrystallization microstructure consisting of entirely large Goss grains was produced. The magnetic induction B 8 and iron loss P 10/400 was 1.79 T and 6.9 W/kg, respectively. [ABSTRACT FROM AUTHOR]