The selective abnormal growth of Goss grains in magnetic sheets of Fe-3%Si (grade Hi-B) induced by second-phase particles (AlN and MnS) was studied using a modified Monte Carlo Ports model. The starting microstruc...The selective abnormal growth of Goss grains in magnetic sheets of Fe-3%Si (grade Hi-B) induced by second-phase particles (AlN and MnS) was studied using a modified Monte Carlo Ports model. The starting microstructures for the simulations were generated from electron backscatter diffraction (EBSD) orientation imaging maps of recrystallized samples. In the simulation, second-phase particles were assumed to be randomly distributed in the initial microstructures and the Zener drag effect of particles on Goss grain boundaries was assumed to be selectively invalid because of the unique properties of Goss grain boundaries. The simulation results suggest that normal growth of the matrix grains stagnates because of the pinning effect of particles on their boundaries. During the onset of abnormal grain growth, some Goss grains with concave boundaries in the initial microstructure grow fast abnormally and other Goss grains with convex boundaries shrink and eventually disappear.展开更多
The significant occupancy of {411}〈148〉texture exists in the thin-gauge grain-oriented silicon steel(TGCRGO is defined that thickness of the sheet is〈0.25 mm and the reduction in cold rolling is more than 90%) wh...The significant occupancy of {411}〈148〉texture exists in the thin-gauge grain-oriented silicon steel(TGCRGO is defined that thickness of the sheet is〈0.25 mm and the reduction in cold rolling is more than 90%) which has been considered to have obviously effects on the abnormal growth of Goss-oriented grains during the secondary recrystallization process. The microstructures of the TG-CRGO were investigated by X-ray diffraction and electron back-scattered diffraction in this study. It was found that {411}〈148〉〉texture mainly exists in the center layer of hot-rolled as well as normalized plates.With the increase in cold rolling reduction, {411}〈148〉 orientation gradually rotates to a-fiber texture(〈110〉//RD).Finally, few {411}〈148〉would retain at the boundaries of deformed a-fiber grains(〈110〉//RD) as the reduction in cold rolling reaches 90%. After annealing treatment, a small amount of c-fiber textures(〈111〉//ND) preferably nucleates and recrystallizes between the DBs(deformation bands) at first; then, the {411}〈148〉 recrystallization texture occurs and mainly nucleates at the grains boundaries of the deformed a-fiber grains, and also quite a few {411}〈148〉orientation grains nucleate in the inner of {112}〈110〉grains. But this phenomenon was not observed in the {100}〈011〉deformation grains.With respect to the occurrence of {411}〈148〉recrystallization texture, it is mainly induced by strong a-fiber as well as weak c-fiber textures formed during cold rolling other than originating from {411}〈148〉 regions in hot bands.展开更多
基金financially supported by the National Key Research and Development Program of China(No 2016YFB0700505)the China’s State Grid Corporation of Science and Technology Projects(No.SGRI-WD71-13-002)+1 种基金the National Natural Science Foundation of China(Nos.51571020 and 51371030)the Nationa High Technology Research and Development Program of China(No.2015AA034201)
文摘The selective abnormal growth of Goss grains in magnetic sheets of Fe-3%Si (grade Hi-B) induced by second-phase particles (AlN and MnS) was studied using a modified Monte Carlo Ports model. The starting microstructures for the simulations were generated from electron backscatter diffraction (EBSD) orientation imaging maps of recrystallized samples. In the simulation, second-phase particles were assumed to be randomly distributed in the initial microstructures and the Zener drag effect of particles on Goss grain boundaries was assumed to be selectively invalid because of the unique properties of Goss grain boundaries. The simulation results suggest that normal growth of the matrix grains stagnates because of the pinning effect of particles on their boundaries. During the onset of abnormal grain growth, some Goss grains with concave boundaries in the initial microstructure grow fast abnormally and other Goss grains with convex boundaries shrink and eventually disappear.
基金financially supported by the China’s State Grid Corporation of Science and Technology Projects (No. SGRI-WD-71-13-002)the National Natural Science Foundation of China (No. 51171019)
文摘The significant occupancy of {411}〈148〉texture exists in the thin-gauge grain-oriented silicon steel(TGCRGO is defined that thickness of the sheet is〈0.25 mm and the reduction in cold rolling is more than 90%) which has been considered to have obviously effects on the abnormal growth of Goss-oriented grains during the secondary recrystallization process. The microstructures of the TG-CRGO were investigated by X-ray diffraction and electron back-scattered diffraction in this study. It was found that {411}〈148〉〉texture mainly exists in the center layer of hot-rolled as well as normalized plates.With the increase in cold rolling reduction, {411}〈148〉 orientation gradually rotates to a-fiber texture(〈110〉//RD).Finally, few {411}〈148〉would retain at the boundaries of deformed a-fiber grains(〈110〉//RD) as the reduction in cold rolling reaches 90%. After annealing treatment, a small amount of c-fiber textures(〈111〉//ND) preferably nucleates and recrystallizes between the DBs(deformation bands) at first; then, the {411}〈148〉 recrystallization texture occurs and mainly nucleates at the grains boundaries of the deformed a-fiber grains, and also quite a few {411}〈148〉orientation grains nucleate in the inner of {112}〈110〉grains. But this phenomenon was not observed in the {100}〈011〉deformation grains.With respect to the occurrence of {411}〈148〉recrystallization texture, it is mainly induced by strong a-fiber as well as weak c-fiber textures formed during cold rolling other than originating from {411}〈148〉 regions in hot bands.