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The improvement of recrystallization texture and magnetic properties in grain-oriented electrical steel with trace Bi addition processed by strip casting process was studied in this study. Low casting temperature and sufficient liquid steel flow during strip casting process enabled relatively homogeneous distribution of Bi in the as-cast strip, which accelerated the precipitation during solidification and cooling process. As a result, relatively high density of duplex MnS + AlN, MnS and AlN was formed at grain boundaries and inside grain. Due to the synergistic effect of continuous precipitation and fragmentation of coarse precipitates during cold rolling, the number density of precipitates was increased and mean size was decreased along the processing route. High density of precipitates is attributed to severe inhomogeneous plastic deformation, which promoted the formation of high density in-grain shear bands during cold rolling and recrystallization Goss texture during annealing. Homogeneous microstructure with average grain size of ~ 11.6 μm, strong Goss texture with intensity of 2.5 multiples of random distribution, fine precipitates with number density of ~ 1.9 × 109 /cm2 and mean size of ~ 49 nm were formed after primary recrystallization annealing. Furthermore, grain-oriented electrical steel with Bi addition experienced complete secondary recrystallization of exact Goss grains during high-temperature annealing, which is attributed to beneficial optimization of Goss texture and strong inhibition effect, and superior magnetic induction B8 of 1.91 T was obtained. It is expected that this study paves a new way for fabrication of high-performance grain-oriented electrical steel.

Cube texture and microstructural evolution of as-cast non-oriented silicon steel (1.3% Si) during cold rolling and annealing were studied. The results showed that the as-cast microstructure with grain size in the range of 100–500 μm had a weak texture. The strong orientation was mainly located at {100} and {110} planes. A significant content of shear-deformed grains oriented with {110}&lt, 110&gt, were obtained by cold-rolling, and many regions oriented with Cube texture were distributed in the shear bands. During cold-rolling, the orientation of the shear-deformed microstructure tilted towards the {111}&lt, 112&gt, orientation, while the matrix orientation retained {110}&lt, On further cold-rolling, the residual part of {110}&lt, experienced shear deformation, forming more shear bands, strengthening the Cube orientation. During annealing, Cube orientation grains nucleated in the shear bands leading to strong Cube texture, and corresponding B50 was 1.83T/1.79T.

The Nb-bearing grain-oriented silicon steel sheets were produced by conventional route and novel twin-roll casting route, respectively. The microstructure, texture and precipitate evolution were comparatively investigated by using electron backscattered diffraction (EBSD) and transmission electron microscope (TEM). The findings revealed that the precipitation behavior and the texture evolution were totally different between the two processing routes. In the conventional route, a great number of nanoscale niobium nitride particles (NbN), which acted as mainly grain growth inhibitors were precipitated during hot rolling, while in the twin-roll casting route, due to the rapid solidification, the precipitation of NbN were suppressed and a new type Nb-bearing precipitate enriched with sulfur element was observed in the as-cast strip. Besides, the primary recrystallized texture of conventional specimens was characterized by strong &gamma, fiber with a peak at {111} &lt, 110&gt, together with very few Goss components. While in the case of twin-roll casting specimens, the strongest primary recrystallized texture was {111} &lt, 112&gt, texture and the area fraction of Goss component was much higher than that of conventional specimens. After final high temperature annealing, complete secondary recrystallization was obtained in twin-roll casting specimens and the magnetic induction of B8 was 0.1 T higher than that of conventional specimens.

Grain-oriented silicon steels were produced by the shortest processing route involving twin-roll strip casting, two-stage cold rolling with intermediate annealing, and simulated continuous annealing. The secondary recrystallization behavior of grain-oriented silicon steels under different inhibition conditions was in-situ observed by combining the confocal laser scanning microscopy (CLSM) and electron backscattered diffraction (EBSD) techniques. The results revealed that the optimal temperature of secondary recrystallization showed a proportional relationship with the Zenner pinning force. In the case of weak pinning force, the abnormal grain growth occurred quickly at ~1050 &deg, C. The corresponding growth rates were in the range of 60&ndash, 1400 &mu, m/min and decreased gradually as the secondary recrystallization proceeded. In the case of strong pinning force, the incubation time and onset temperature of the secondary recrystallization was significantly increased, but the total time of the secondary recrystallization was obviously shortened from 685 s to 479 s, and the final magnetic induction of B8 was increased from 1.7 T to 1.85 T. After the secondary annealing, some island grains and coarse primary grains were retained. The formation of island grain was related to the low migration of grain boundaries. The findings of coarse &gamma, grains indicated that the primary grain size also played a crucial role during secondary recrystallization, apart from the primary recrystallized texture, which attracted more attention previously.

Lili Yuan,1,* Yuanxiang Zhang,2,* Di Luan,1 Xiangjun Xu,1 Qian Yang,1 Shoucai Zhao,1 Zhiming Zhou1 1Department of Neurology, The First Affiliated Hospital of Wannan Medical College, Wuhu, Anhui Province, People’s Republic of China; 2Department of Clinical Pharmacy, The First Affiliated Hospital of Wannan Medical College, Wuhu, Anhui Province, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lili YuanDepartment of Neurology, The First Affiliated Hospital of Wannan Medical College, Wuhu, Anhui Province 241000, People’s Republic of ChinaEmail molly8338@126.comIntroduction: Affective symptoms and attention impairments are found in patients with hyperthyroidism. Our previous data have revealed that the patients with hyperthyroidism experience impairments of the attention networks, but it remains unclear whether these disorders persist after the treatment of hyperthyroidism.Methods: Twenty healthy controls and 25 hyperthyroid patients were recruited and performed the attention network test (ANT) which can simultaneously examine the alertness, orientation and execution control components of the participants. The effect of treatment on affective symptom and attention networks impairments were examined in the patient group after 1-year anti-thyroid medication and reaching euthyroidism for at least 3 months.Results: Anxiety and depression scores of patients with hyperthyroidism were significantly higher than those of the healthy control group. The patients with hyperthyroidism had impairments of the alerting and executive control networks. Meanwhile, the score of HAMA correlated significantly with thyroid hormone and TSH levels, and there was a negative significant correlation between the score of HAMD and TSH level in all subjects. There was a positive correlation between the value of the executive control network and thyroid hormones’ levels in all subjects and in the hyperthyroidism group. Anxiety and depression symptoms were improved with methimazole treatment after euthyroidism was reached. The value of the executive control network no longer differed from that of healthy controls, but deficits in the alerting network of hyperthyroidism still persisted after treatment.Conclusion: The patients with hyperthyroidism existed affective symptoms and attention networks impairments. Affective symptoms and attention executive control network impairment were improved following thyroid function normalization in hyperthyroidism.Keywords: hyperthyroidism, thyroid hormones, cognition, affective symptoms, attention network test

The study described here focuses on the microstructure and mechanical properties of a novel hot-rolled medium-Mn steel (Fe–0.25C–4Mn–1.88Al–0.6Si–0.04Nb–0.08V, wt%) that contained only 4 wt% Mn and modest Al content of 1.88 wt%. It was found that a relatively high content (25–53 vol%) of retained austenite was obtained by intercritical annealing process. With increase in intercritical annealing temperature from 700 to 740 and to 760 °C, retained austenite fraction increased from 25.1 to 53.2% and then decreased to 46.1%. Besides, mechanical stability of retained austenite in 700–760 °C intercritically annealed steels decreased with increase in intercritical annealing temperature. The 720 °C intercritically annealed steel yielded excellent mechanical properties with yield strength of 766 MPa, tensile strength of 951 MPa, total elongation of 48.6% and PSE of 46.22 GPa·%, achieved by a high volume fraction of retained austenite (46%) with relatively high mechanical stability. Thus, the 4% Mn steel present in this study indicated excellent mechanical properties of medium-Mn steels can be achieved using low alloy content.

The effect of rolling temperature on the evolution of microstructure, texture, and magnetic properties of ultra-low-carbon grain-oriented silicon steel was studied in strip-casting process. Dynamic strain-aging (DSA) behavior was observed during warm rolling in the temperature range of ~ 200 to 400 °C based on the fact that majority of the inhibitor elements remained in solution during the strip-casting process. Considering the initial coarse grains with strong {100} fiber prior to rolling, the cold-rolled specimen exhibited pronounced α-fiber and weak γ-fiber texture. However, intense shear bands and high stored energy regardless of the orientation were obtained in the warm-rolled specimens at the DSA temperature, accompanied by weak α-fiber and strong γ-fiber texture. While homogenous microstructure with lower stored energy was observed in the case of high temperature, the differences in shear bands and stored energy governed by the rolling temperature were strongly related to the extent of DSA effect, which is attributed to distinct characteristic of rolling and recrystallization texture. After recrystallization annealing, fine-grained homogeneous microstructure with strong Goss and γ-fiber texture was obtained at the DSA temperature, while relatively random texture with much more α-fiber and θ-fiber components was observed in the case of high temperature. The microstructure and texture of primary annealed sheets exhibited sufficient Goss grains and favorable surrounding matrix with pronounced γ-fiber texture, which was responsible for the perfect secondary recrystallization annealing in the warm-rolled specimens at the DSA temperature. The present study suggests that texture optimization of strip-cast grain-oriented silicon steel can be achieved by warm rolling in the appropriate temperature range, with improved magnetic properties.

The shear-compression deformation of GH4169 superalloy at 1000–1200 °C and 0.01–1 s−1 was investigated by physical and numerical simulation based on a specific shear-compression sample (SCS). OM, EBSD, and TEM analysis revealed the three typical regions in SCS. Dynamic recrystallization (DRX) preferred to occur in the slot region due to the strain concentration, where the Mises equivalent strain was about 4–6 times higher than the pre-set ones. Mixed grains were observed in the transition region because of insufficient deformation. In contrast, equiaxial grains were preserved in the cylindrical region with negligible deformation. Experimental stress decreased with the increase of temperature and decrease of strain rate. The maximum stress was 180 MPa, which was only 30% of that under single compression deformation. Furthermore, four DRX mechanisms were observed in GH4169. Discontinuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX) were the dominant and auxiliary mechanisms, respectively. Twinning dynamic recrystallization (TDRX) occurred in the annealing twins with a fast nucleation rate, and the intersected nano-twins provided favorable nucleation sites for DRX. Lastly, secondary dynamic recrystallization (SDRX) with unique nucleation mechanism of triangularly intersecting subgrain boundaries emerged in SCS, which nucleated in the DRX grains and further refined the microstructure of GH4169.

Texture optimization has always been a challenge to fabricate non-oriented electrical steels (NOES). In the present study, thin-gauge NOES with high permeability was successfully processed using an innovative and convenient twin-roll strip casting process without hot rolling. The relation between the as-cast microstructure, processing route and texture evolution was studied. The results indicated that as-cast strip with coarse grains exhibited strong {100}〈0vw〉 texture and unique {110}〈110〉 component. Annealed sheets processed by one-stage rolling displayed pronounced {111}〈112〉, {223}〈110〉 components and weak Cube and Goss texture. Micro-texture characteristics revealed that {100}〈0vw〉 texture was partially retained from initial grains, and new Cube and Goss substructures were generated within {110}〈110〉 deformed grains during cold rolling. This was responsible for the development of Cube and Goss recrystallization texture. Furthermore, the application of two-stage rolling not only reinforced these two behavior, but also accelerated the nucleation of η grains because of the increased shear bands in cold-rolled sheets. In this manner, an improved texture consisting of dominant η-fiber, weak γ-fiber and optimized magnetic properties (B50 = 1.72 T, P10/400 = 14.91 W/kg) were obtained. Keywords: Thin-gauge non-oriented electrical steel, Twin-roll strip casting, Microstructure, Texture, Magnetic properties

Strip-cast grain-oriented 4.5% Si steel was produced by short-term isochronal secondary annealing (15 min) and isothermal annealing (1000 °C) under hydrogen atmosphere. The relationship between the evolution of grain structure and magnetic properties was elucidated. It was observed that during isochronal annealing, abnormal grain growth occurred followed by normal grain growth with the increase of annealing temperature. Additionally, decreasing the primary annealing temperature accelerated the isochronal annealing kinetics, and near complete abnormal grain growth with optimal magnetic properties was obtained at lower temperature. Furthermore, during isothermal annealing, abnormal grain growth successfully occurred and magnetic properties were continuously improved with the increase of annealing time. The optimal magnetic properties were superior to those of isochronal annealing because of sharper secondary Goss texture and reduced retention of second-phase particles. The grain-oriented 4.5%Si steel in the present study indicated superior properties and better workability than the previously reported non-oriented 6.5%Si steel. Thus, grain-oriented 4.5%Si steel produced by short-term secondary annealing can potentially replace non-oriented 6.5%Si steel.

A Fe-3.0%Si non-oriented silicon steel was produced by a novel strip casting process. Cold-rolled sheets were annealed at temperatures varying from 900 to 1200 ° C with the aim to investigate the influence of recrystallization annealing process on the microstructure, texture and magnetic properties. The increase in annealing temperature significantly increased the recrystallized grain size and reduced the core loss. However, the oversized microstructure (~360 μm) in 1200 ° C annealed sheets resulted in an augment in core loss. In addition, with increasing annealing temperature, the magnetic induction diminished along the rolling direction while gradually increased along the transverse direction, even though the average value changed slightly. This interesting result could be attributed to the weakening in η -fiber and strengthening in λ -fiber and γ -fiber texture. The best combination of core loss (3.23 W/kg), magnetic induction (1.71 T) and anisotropy was obtained at recrystallization annealing of 1100 ° C. The specified and unspecified errors in this paper have been carefully corrected, and