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To improve the cleanliness of oriented silicon steel, industrial experiments are performed under different refining slag composition conditions. The results show that the use of medium‐basicity refining slag (w(CaO)/w(SiO2) = 2.3–2.6, w(CaO)/w(Al2O3) = 2.3–2.6) results in higher steel cleanliness with lower Al2O3 volume fraction, and smaller inclusions. In addition, the thermodynamic equilibrium between the oriented silicon steel slag and the molten steel is investigated at a temperature of 1873 K (1600 °C) to understand the effect of different slag compositions on the oxygen content and Al2O3 absorption capacity. Furthermore, a mathematical model is introduced to describe the behavior of inclusions at the steel–slag interface as well as to predict the removal of oxide inclusions during the slag‐refining process. The experimental and predicted results for inclusion removal after slag refining are in good agreement. [ABSTRACT FROM AUTHOR]

The cold rolling and intermediate annealing process, along with the incorporation of rare earth elements, play an important role in the microstructure, texture, and inhibitors of oriented silicon steel. Currently, there is limited research on the impact of rare earth yttrium on texture evolution during the cold rolling and intermediate annealing processes. Therefore, the effects of different cold rolling deformations and intermediate annealing temperatures on the microstructure and texture of Y bearing oriented silicon steel have been studied. The experimental results demonstrate that the average grain size of the intermediate annealed plate progressively decreases with increasing the cold rolling deformation. This is because the high cold rolling deformation brings more additional dislocations and distortions, consequently enhancing the driving force for recrystallization. Observing the microstructure with various cold rolling deformation, the results show that the annealed plate with a 72 % reduction rate exhibited the highest Goss texture percentage of 4.83 %. This is because the cold-rolled sheet with a reduction rate of 72 % exhibits an abundance of Goss oriented substructures. These substructures quickly dominate the {111} deformed matrix during the initial recrystallization, and promote grains nucleation and growth. As the annealing temperature increases, the driving force for the growth of recrystallized grains also increases, leading to a gradual increase in grain size. The plate annealed at 940 °C exhibits the highest percentage (4.83 %) of Goss texture. The addition of rare earth Y can lead to an increase in grain size in the intermediate annealed plate and facilitate the formation of {411} texture. This is advantageous for the abnormal growth of Goss texture. The results demonstrate that a cold rolling deformation rate of 72 % and an intermediate annealing temperature of 940 °C are good for promoting abnormal growth of Goss orientation. The study results on precipitation kinetics suggests that the grain boundary nucleation of AlN and dislocation nucleation of MnS are the most effective way of nucleation. The precipitates in oriented silicon steel without Y are Al2O3 and MnS, while those in the samples with Y are AlN, YS, and YOxSy. The addition of rare earth Y leads to a reduction in both the density and size of precipitates. Moreover, With the increase of annealing temperature, the size of precipitates decreases and the amount of precipitates increases. Additionally, the addition of Y makes the steel more clean, meanwhile, the pinning effect of inclusions on grain boundaries is weakened. Therefore, the grain size of the steel with Y is larger.

Low temperature heating process of the slab has become the mainstream process for producing high quality oriented silicon steel due to its environmental protection, low cost, and high yield. For this process, the number of inhibitors is less and the size is large, resulting in insufficient inhibition, coarsen grains during primary recrystallization, and insufficient driving force for secondary recrystallization, which reduces the magnetic properties of the product. These shortcomings can be improved by optimizing the inhibitors and normalizing processes. The effects of normalizing processes on the microstructure, texture, and precipitations of low-temperature oriented silicon steel containing Sn were studied by OM, SEM, TEM, and EBSD with Fe–3%Si hot-rolled plate as initial material. The experimental results show that the sample has the best performance in terms of microstructure, texture, and precipitations with the two-stage boiling water cooling normalizing process that the heating temperature is 1150 °C, and the normalizing intermediate temperature is 850 °C. With the above parameters, the microstructure is inhomogeneous along thickness. There are more {111} textures, which are favorable to the growth of Goss texture. The proportion of high energy grain boundary reached 54.2%. The precipitates are significantly refined, which enhances the ability to inhibit primary recrystallization. The sub-surface thickness of the hot rolled plate increases from 40.6% to 62.1% with increasing Sn content from 0.01% to 0.11%. The degree of tin segregation at grain boundary increases with the increase of normalizing temperature and the decrease of medium soaking temperature.

Based on the understanding that the essence of secondary recrystallization of Goss texture is to restrain the abnormal growth of {110}<112>, {210}<001> and partial Goss texture {110}<225>, it was concluded that making sharp Goss grow up becomes the only choice. It was proposed that the abnormal growth mechanism of Goss texture was the result of selective generation, directed inheritance, and selective growth. The mechanism explained that the Goss texture was the most easily formed shear texture. In directed inheritance, the Goss texture was required to be highly compatible with the near-constant of the second-phase particle inhibition force, providing an optimal environment for the abnormal growth of the Goss texture by controlling the inhibition force near-constant. The control of the near-constant inhibition force provides an optimal environment for the abnormal growth of the Goss texture. Based on that, the process technology for producing low-temperature nitrided-oriented silicon steels and steel products was successfully developed. [ABSTRACT FROM AUTHOR]

The effect of rare earth Y on precipitates and textures of the grain-oriented silicon steels, the composition, morphology, size, quantity of inclusions and texture evolution of hot-rolled and cold-rolled oriented silicon steel containing rare earth Y were studied using transmission electron microscopy, field emission scanning electron microscope, and electron backscatter diffraction. The results show that there are mainly spherical or ellipsoidal Y2O2S precipitates in the Y bearing silicon steel. Rare earth treatment effectively improves the precipitates’ morphology and restrains the precipitation of the long-strip MnS in the hot-rolled plate. Meanwhile, the microstructure is more uniform, and the recrystallized grains on the surface and the fiber structure in the central layer are larger after hot rolling compared with Y-free steel. Furthermore, with the addition of rare earth Y, the unfavorable brass texture and rotational cube texture in the hot-rolled plate are reduced. Meanwhile, the number of shear bands is increased and the strength of the favorable {111} 〈112〉 texture is improved in the cold-rolled plate, which helps develop the Goss texture during the annealing process.

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Surface oxidation of the oriented silicon steel usually occurs during the first soaking in annular furnace. It negatively influences the magnetic performance and the MgSO4 coating of the strip. The surface oxidation is closely related to the high H2O content atmosphere between the layers of the strip. As the H2O content within the coil is hard to measure, the mass transfer model of the oriented silicon steel coil during the first soaking in annular furnace is built in this paper. Furthermore the correlations between H2O content and the magnetic performance distribution are also analyzed via experiment in actual production. The result shows that the H2O content within the coil increased as the height declined in axial direction. Plenty of H2O concentrated near the bottom of the coil as a result of the tight joint between the coil and the plate. The maximum H2O content within the coil is about 80 vol%. The magnetic performance of the strip tended to decline while the H2O content rose especially at the edge of the strip. Most magnetic property defects appeared at the outer ring and the bottom of the coil. The oxidizing atmosphere between the layers of the strip could be weakened significantly through improving the diffusion conditions at the bottom surface of the coil. [ABSTRACT FROM AUTHOR]

Based on the understanding that the essence of secondary recrystallization of Goss texture is to restrain the abnormal growth of {110}, {210} and partial Goss texture {110}, it was concluded that making sharp Goss grow up becomes the only choice. It was proposed that the abnormal growth mechanism of Goss texture was the result of selective generation, directed inheritance, and selective growth. The mechanism explained that the Goss texture was the most easily formed shear texture. In directed inheritance, the Goss texture was required to be highly compatible with the near-constant of the second-phase particle inhibition force, providing an optimal environment for the abnormal growth of the Goss texture by controlling the inhibition force near-constant. The control of the near-constant inhibition force provides an optimal environment for the abnormal growth of the Goss texture. Based on that, the process technology for producing low-temperature nitrided-oriented silicon steels and steel products was successfully developed.

In order to study the effect of cold-rolling deformation and rare earth Y on the microstructure and texture of 3.0% Si-oriented silicon steel, the microstructure and texture of cold-rolled oriented silicon steel with 60, 72, and 86% deformation are analyzed using electron backscatter diffraction and image analysis software. The experimental results show that the deformation band becomes narrower and the distribution of shear bands becomes denser with increasing cold-rolling deformation. Compared to the Y-free steel, cold-rolled sheet containing rare earth Y has greater shear bands. The pinning effect of rare earth Y hinders the dislocation movement, which leads to the increase of kernel average misorientation value and shear bands. With the increase of cold-rolling deformation, the texture concentrates on α and λ. This is mainly due to the change from {100} 〈001〉 to {001} 〈110〉, intensifying λ texture, and the change from {111} 〈112〉 to {111} 〈110〉, thus strengthening the α texture. The texture strength of cold-rolled sheets can be decreased by rare earth Y. But the γ texture strength in cold-rolled sheets containing Y is significantly higher than in those without Y. The γ texture strength can reach up to 7.3, and the strong points are mainly {111} 〈112〉. This is because the number of inclusions in steel increases with the addition of rare earth Y. In the process of grain nucleation, the {111} oriented grains nucleate heterogeneously on the inclusions. It forms a large number of {111} oriented grains and improves the γ texture strength.

The research object of this paper is the common oriented silicon steel (CGO) with Si content of 3.1%. The magneto-thermal coupling processing device independently developed was used to conduct laboratory studies on magneto-thermal coupling decarburization annealing, magneto-thermal coupling high temperature pre-annealing and magneto-thermal coupling tensile leveling annealing. The microstructure and macroscopic texture of CGO steel after magneto-thermal coupling treatment were measured by Zeiss microscope and X-ray diffrotometer, and compared with the samples after conventional annealing process. The results show that the magneto-thermal coupling treatment at the decarburization annealing stage can promote the distribution of ferritic grains along the magnetic field direction. The cubic texture {001}<100> with high level fault energy and {111}＜112＞ texture also increases. In the high temperature pretreatment stage, the increase of {111}＜112＞ texture is more obvious after magnetic-thermal coupling treatment. The deviation angle of goss-oriented grain decreases after magneto-thermal coupling treatment in tensile leveling stage. The magneto-thermal coupling effect plays a positive role in the microstructure and texture of CGO steel during decarburization annealing, high temperature pre-annealing and tensile leveling annealing. [ABSTRACT FROM AUTHOR]

Oriented silicon steel is vital for power transformer cores, while the high-temperature annealing process limits the industrialization of environmentally friendly coatings on the surface. In this paper, the high-temperature binders Al(H2PO4)3 solution and silica sol were introduced innovatively. They condensed into macromolecular polymer chains, network structures and SiO2 particles at high temperatures, providing high-temperature stability and adhesion. The influence of types of silica sol, additives and functional fillers on the corrosion resistance of the coating was studied. The prepared environmentally friendly inorganic insulating coating for oriented silicon steel has excellent corrosion resistance after curing at 475 °C and annealing at 800 °C, which was matched with the currently rolling process of oriented silicon steel. The salt-spray resistance can last for more than 24 h and up to 72 h. [ABSTRACT FROM AUTHOR]

The separation of core loss plays an important role in the transformer loss calculation. To obtain more accurate core loss, based on the comparison and analysis on two traditional loss separation methods, an improved loss separation method was proposed for the core loss calculation of the transformer in a wide magnetic flux density range. Firstly, through analysis the eddy current loss was obtained by direct calculation, while the hysteresis loss was obtained by performing the quasi-static magnetization process. And the coefficient corrections for the hysteresis loss and eddy current loss calculation were conducted by using the experimental data. The result comparison between the proposed method and traditional ones were made. Secondly, by setting up the Epstein frame platform, the total loss and static hysteresis loss of 14 types of industrial silicon steel were measured. In addition, the suggestive values and the corresponding value range of the loss coefficients of 14 kinds of industrial silicon steel were given. The results obtained by the proposed method were in good agreement with the measured data in the wide magnetic flux density range, while the suggestive values and the corresponding value range of 14 kinds of industrial silicon steel can provides an effective data support for the accurate core loss calculation.

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Thrust performance is one of the important indexes of permanent magnet linear synchronous motors. The traditional non-oriented silicon steel sheet is used as the core material of the permanent magnet linear synchronous motor, which limits the performance of the permanent magnet linear synchronous motors. For the oriented silicon steel sheet has a higher magnetic permeability in the rolling direction, a permanent magnet linear synchronous motor with similar number of pole and slot made of oriented silicon steel is proposed in this paper. By measuring the B-H curves of the rolling direction and the cutting direction, the thrust properties of the two motors made of traditional silicon steel sheets and oriented silicon steel sheets are analyzed and compared by the finite element method (FEM) under rated load and overload conditions respectively. The thrusts under different tooth-yoke ratio are discussed in the end. [ABSTRACT FROM AUTHOR]

Balance solubility products and enthalpy of formation for NbC, NbC, NbC, NbC and NbN in oriented silicon steels were calculated and compared qualitatively. Meanwhile, the mixing enthalpies of these five Nb compounds were calculated based on Miedema Model. The results show that the solubility products of Nb compounds in ferrite and austenite meet the following relationship, NbC > NbC > NbC > NbC > NbN and NbN has the minimum enthalpy of formation. It indicates that NbN easily precipitate out, but it is more difficult for NbC. [ABSTRACT FROM AUTHOR]

Abstract: The effect of pulsed magnetic primary annealing on the microstructure and texture of two-stage cold-rolled silicon steel is investigated. Specimens are annealed at 700°C for 1h under a 1T pulsed magnetic field along different directions with respect to the sample coordinate system. Crystallographic orientation and grain size are identified by analyzing electron backscattered diffraction pattern. The effects of magnetic field treatment are related to the magnetic field direction. Based on the anisotropy energy of ferromagnetic material during magnetic annealing, a hypothesis is proposed. All of the experimental results in this work support the proposed model. [Copyright &y& Elsevier]

High functionality given to steel products results in incremental environment loads at the steelmaking stage. However, at the stage of utilization, high-functional steel products prove more environment friendly than their conventional counterparts in many cases. Therefore, evaluation on contribution of steel products to environmental improvement requires an integrated approach that considers the product over its entire life cycle - life cycle assessment (LCA). This paper discusses the relationship between the improvement of steel products performance and environmental impact from the entire life cycle perspectives. The LCA method to calculate and assess contribution of high-functional steel products during the life cycle to environmental improvement is explained. Two case studies of Baoshan Iron & Steel Co., Ltd. (Baosteel for short) are given to show that LCA is a scientific and systematic method for eco-materials evaluation or eco-design: ➀ in a power transformer, using silicon steel B30P110 to replace B30G130 can reduce carbon dioxide emissions in the region of 15.1% over the life cycle of the power transformer; ➁ tinplate steel of Baosteel for two-piece steel cans experienced six times thickness reduction from 0.280 to 0.225mm, which results in 14.5% emission reduction over the life cycle of two-piece steel cans. It is a systematic and scientific method for evaluating on products environmental performance from life cycle perspective. [ABSTRACT FROM AUTHOR]