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Grain oriented electrical steel is an important core material of transformers. Its magnetic properties significantly affect the energy efficiency of electrical apparatus. Inclusions are used as inhibitors to impede the normal grain growth of grain oriented electrical steel during the primary recrystallization. But, abnormal grain growth occurs to develop the preferred Goss texture during secondary recrystallization. Secondary recrystallization behaviors are influenced by its inclusion inhibitors. In this study, we systematically investigate the effect of reheating temperature and time on the size and distribution of inclusions of four extra low carbon silicon steels with various sulfur, maganese and aluminum contents. The experimental results from chemical analysis could be fitted with a singleline represented by an equation applicable to MnS. Log[Mn(wt%)*S(wt%)]=-2683/T-0.8197 where T is in kelvins. As same as, the solubility products of aluminum nitride could be fitted with a single line represented by an equation. Log[Al(wt%)*N(wt%)]=-4809/T-1.4165 The solubility products of inclusion increase with the get long time. Inclusion sizes are decreased with elevate reheating temperature. At high temperature, activation energy of inclusion elevates the diffusion coefficient , So, the dissolved rate increase with the elevated reheating temperature. As the time of inclusion dissolved increase, any size inclusion is decrease with time keep reheating temperature. In compnnent of inclusion, the count and distribution of inclusion is elevated by increased sulfur and aluminium contents.
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