The processing route of grain oriented electrical sheet was simulated by laboratory trials. Besides MnS, the effect of AlN and NbC as an inhibitor phase in 3 percent silicon steel was also investigated. In the hot strip material the niobium microalloyed steel showed the highest volume fraction of the {110} Goss texture at 0.3 to 0.4 mm below the surface. This superiority was maintained after cold rolling and annealing after both, one step or two step cold reduction schedules. A volume fraction of the Goss texture of more than 80 percent is typical for this steel concept. It can be explained by the solubility product of NbC, which guarantees grain size control during the primary recrystallisation processes and allows the Goss texture component to grow during secondary recrystallisation, which usually follows a steel decarburisation. Consistent with highest volume fraction of Goss texture, the core losses are lowest in the sheet using NbC as an inhibitor phase.
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