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Copyright of Automobile Technology is the property of Automobile Technology 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.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Silicon carbide (SiC) ceramics can be used as inner lining of reduction tank for magnesium smelting. The interfacial reaction between SiC and heat resistant steel was systematically investigated by diffusion couple experiment under vacuum and 1200 °C. The results show that at the early stage of reaction, the main products of interfacial reaction are metal silicide and graphite, and the lamellar graphite distributing at the interface hinders the interfacial reaction. However, due to the melting of silicon-nickel compounds with low melting point at interface, the lamellar graphite is transformed into fibrous graphite under the catalysis of Ni, losing its protective effect on silicon carbide. In addition, the interface reaction changes from solid-solid reaction to solid-liquid reaction, and the interfacial reaction process is accelerated, which accelerates the corrosion of silicon carbide by steel. Compared with heat resistant steel, the interfacial reaction rate between SiC and pure iron is obviously decreased, and the temperature required for the reaction is obviously increased. Reducing Ni content in heat resistant steel can effectively prevent the reaction between heat resistant steel and SiC. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology 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.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

Copyright of Journal of Materials Science & Engineering (1673-2812) is the property of Journal of Materials Science & Engineering 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.)

In strip casting grain-oriented silicon steels, the inheritance of coarse λ grains (〈100〉//ND, normal direction) can deteriorate their magnetic properties. To solve the problem, twinning behaviors in strip casting grain-oriented silicon steels during hot rolling were investigated in this work. It is found that after rolling at 650℃, a number of 112〈111〉deformation twins are formed in the coarse solidification microstructure of the steels, in contrast to the well-accepted view that it is difficult to trigger twinning at relatively high temperature in the grain-oriented silicon steels with high stacking-fault energy. The results indicate that the complex stress state during hot rolling may weaken the orientation dependence of deformation twinning. Due to higher stored energy, the intersections of twin/twin boundaries and twin/grain boundaries can act as the preferential nucleation sites for the recrystallized grains during normalizing annealing, leading to a significant increase of recrystallization rate. Because of the restriction from local strain partitioning and the limited size between the twins, the shape of new-formed recrystallized grains is mainly plate-shaped. Consequently, the fine grains with scattered orientations are formed in the normalized microstructure and the coarse λ grains in the solidification microstructure are eliminated. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

A permanent motor remanufacturing method was proposed, the components such as he casing, the end cover and the rotor were retained, and the stator was replaced by a hybrid stator ore formed by axially laminating of amorphous alloy and silicon steel. Taking a hybrid stator core re-manufacturing motor as object, the axial distribution of the no-load gap magnetic flux density was analyzed; the radial force density corresponding to the amorphous alloy stator and the silicon steel stator was calculated, and the strain numerical analysis of remanufactured motor was analyzed by the electromagnetic-mechanical coupling model; the axial distribution law of unit electromagnetic torque of remanufacturing motor was studied; the formula for calculating electromagnetic torque of remanufacured motor was deprived, and the torque imbalance caused by the unequal electromagnetic torque between amorphous alloy stator and silicon steel stator was found; the influences of torque imbalance on motor core were analyzed. The remanufactured motors were fabricated and subjected to a vibration test, and the testing results confirm the correctness of the analysis. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

The as-cast structure of high-silicon steel ingots under different cooling conditions was studied in this paper. It is found that the as-cast structure of the ingot is formed mainly by coarse columnar crystals, especially in the water cooling ingot, and the ratio is reaches as 90%. The dendrite tip growth kinetic coefficients and Gauss distribution parameters for 3D-CAFE simulation were determined according to the compositions of high-silicon steel and the results of as-cast structure. Then the solidification process of high-silicon steel under different cooling conditions was simulated by 3D-CAFE method. The results show that the temperature field under air cooling is more uniform, the mushy zone is broader, and it exhibits a transitional solidification pattern, however, which shows a layered solidification pattern under water cooling. The flow field under air cooling is more stable than that under water cooling, there is a remarkable suction region within the feeder head of the air cooling ingot, and this phenomenon is not observed in the water cooling one. The CAFE results including both morphology and grain size show a good agreement with the results from experiments. Moreover, the influence of superheat on the solidification structures was researched to find that the ratio and quantity of equiaxed structures increase with the decrease of the superheat, and the grain size becomes finer.

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

The unique texture evolution and secondary recrystallization behavior of medium temperature reheated grain oriented silicon steel containing copper were analyzed by comparison with those of conventional grain oriented silicon steel and high permeability silicon steel.The results show that to obtain a stronger γ-fiber primary recrystallization texture,which can be easily consumed by Goss grains,recovery annealing and slow heating rate of high temperature annealing are necessary.During the high temperature annealing stage,the strong γ-fiber primary recrystallization texture shows the effects of decreasing the stored energy caused by recovery annealing and increasing the nucleation rate of γ-fiber grains with slow heating rate.The onset temperature of secondary recrystallization exceeding 1000 ℃ and the strong γ-fiber primary recrystallization texture with less non-γ-fiber oriented grains indicate that the secondary recrystallization behavior is dominated by preferred grain growth.As a result,very huge secondary recrystallization grains with smooth boundaries are obtained.The iron loss is increased due to huge secondary grain size characterized in medium temperature reheated grain oriented silicon steel final products,but can be reduced significantly by magnetic domain refinement using laser scribing,compared with that of high permeability grain oriented silicon steel with small secondary grain size.

The microstructure and texture evolution of Hi-B steel produced by thin slab casting and rolling (TSCR) process in the laboratory was studied by metalloscopy and scanning electron microscopy. It was found that the microstructure and texture of the hot rolling slab of Hi-B steel, which was manufactured by simulated TSCR process in the laboratory, was inhomogeneous along the thickness direction. Ferrite grains in the surface decarbonization layer of the normalizing slab obviously coarsen; moreover, the texture of the normalizing slab inherited the texture type of the hot rolling slab, with only a difference in texture density. After cold roiling with big reduction rate, the coarse grains and grain boundaries were stretched to be fibrous bands in the rolling direction, and the α fiber texture and the γ fiber texture were the main texture style. With the deearburizing annealing carrying out, the recovery and reerystallization of the cold rolling slab occurred, primary recrystallization grains formed, and the texture was more centrally distributed. When the temperature increased to 1000℃, secondary recrystallization appeared; at 1010℃ the Goss grains grew up, and the Goss texture intensity reached to 61. 779. By testing, the products had a magnetic induction of 1. 915 T and an iron loss of 1. 0671 W.kg-1.

High silicon steel with an initial near columnar-grained structure was directly hot-rolled and followed by subsequent warm-rolling,cold-rolling and annealing. Then its microstructure and texture were determined using electron backscatter diffraction,and the magnetic properties of annealed sheets were measured as well. For this high silicon steel,the microstructure and texture evolution of initial near columnar-grained samples represent competitive behavior between fine shear-textured grains near the surface of sheets and coarse grains in the center layer of sheets,which are consisted of α-fiber grains or deformed original cube oriented grains.There are obvious effects of initial columnar grains in the whole process,and a small amount of cube-oriented regions are retained in final annealed sheets,thus the { 111}-fiber texture finally decreases. Furthermore,it is noticed that coarse recrystallized grains are generally related to original cube oriented grains and they are beneficial to the magnetic properties of final annealed sheets. The magnetic properties of annealed sheets in this study are lower than those reported in literature in final sheets with sharp { 120} 〈001〉 or { 001} 〈120〉texture,while they are better than non-oriented high silicon steel. In addition,the difference of magnetic induction between the rolling direction and transverse direction of annealed sheets is small,thus the initial columnar-grained structure is potential to be used in making non-oriented high silicon steel.

The evolution mechanisms of MgO-Al2O3 in the process of calcium treatment in non-oriented silicon steel were studied by laboratory experiments, with focus on the evolution process in the early and middle of calcium treatment. A small amount of MgO-Al2O3 surrounded by AlN was occasionally detected besides many pure spinels before calcium treatment. CaS or CaO formed as a tran-sient inclusion in the MgO-Al2O3 surface 1.5 min after calcium treatment. The composition from the inner part to outer part of inclu-sions was MgO-Al2O3, CaO-MgO-Al2O3 and CaO-Al2O3 in order 4.5 min after calcium treatment. 10 min after calcium treatment, unreacted MgO-Al2O3 spinels disappeared, and simultaneously CaO-MgO-Al2O3 and CaO-Al2O3 inclusions became homogeneous in composition. The phase stability diagrams of Al2O3/MgO-Al2O3/MgO and MgO-Al2O3/xCaO·yAl2O3 were calculated using thermo-dynamic data. The result showed that it was difficult to modify MgO-Al2O3 spinels with very high aluminum content. In combination with the scanning electron microscopy images, energy-dispersive spectra and element mappings of typical inclusions, the evolution route of an inclusion was described as MgO or Al2O3→MgO-Al2O3→CaO-MgO-Al2O3→CaO-Al2O3, and the alumina content occa-sionally showed a sudden increase besides a common decrease in the middle part of the product.

Combined with magnetic property measurements of thin grain-oriented silicon steel sheets annealed to different recrys-tallization stages, the deformation and recrystallization texture and microstructure evolution of the sheets was analyzed by using the electron back-scattering diffraction (EBSD) micro-texture analysis technique and X-ray diffraction texture analysis technique. The results show that the deformation texture transforms from {110}{001}to {111}{112} about the transverse direction. Meanwhile, it should be noticed that additional crystal rotation about RD which leads to the occurrence of a weak{001}{100} texture near the sheet surface appears in deformed grains, thus the origin of a cube recrystallization texture can be explained. As the annealing temperature increases, there occur abnormal grain growth and changes in magnetic properties, which are bound up with texture evolution including a beneficial {110} -{100}{001} texture and other weak texture components. Taking both abnormal grain growth and texture evolution into consideration, it is deduced that secondary and tertiary recrystallization occur. There exists crystallographic rotation about the{001} axis between different kinds of textural components at different recrystallization stages, so the recrystallization texture evolution of the sheets is believed to be driven by the growth dominance of grains having {100} rotational relationship with primary grains and the inhibition effect of the sharp Goss matrix. On the other hand, the abnormal growth of Goss grains induced by the strong advantage of {110} surface energy leads to a sharp Goss texture during tertiary recrystallization after annealing at high temperature for long time.

A silicon steel was treated by using shot peening (SP) and followed by solid powder siliconizing treatment to investigate the possibility of simplify siliconizing operation by means of surface nanocrystallization and effect of siliconizing parameter. The microstructural evolution was examined by using transmission electron microscopy, scanning electron microscopy and X-ray diffraction, respectively. Experimental results showed that nanocrystallines (of about 10 nm in size) with random orientations form in the top surface layer of SP sample. After the siliconizing treatment in Si powder +halide at 550 ℃, a compound layer forms on the SP sample, and its thickness increases with the increasing of the siliconizing temperature and the duration at higher temperature, however keeps unchanged with the increment of halide content. The compound layer consists of FeSi and Fe3 Si phases. The higher temperature and halide content /lower temperature and halide content are helpful for the formation of FeSi /Fe3 Si phases, respectively. [ABSTRACT FROM AUTHOR]