Influence of the Secondary Recrystallization Temperature on the Sharpness of Goss Secondary Recrystallization Texture

Abstract

Primary recrystallized Fe–3%Si specimens containing AI and nitrided were annealed intermittently with the heating rate of 15℃/h in 100% N₂ atmosphere. The magnetic induction B8 was measured after each annealing. The onset of secondary recrystallization was detected by the rapid rise of B8. The maximum B8 obtained was about 1.94 T when the onset temperature of the secondary recrystallization was around 1075℃ regardless of the initial grain size or nitrogen content.The same primary specimens were coated with MgO and annealed with the same heating rate in 5% H₂–N₂. The maximum B8 obtained was nearly same as with the above annealing condition, however, the initial grain size and nitrogen content was quite contrary in this annealing. The difference in the optimum grain size and nitrogen content for obtaining the highest B8 between both annealings was explained on the assumption that ∑9 boundaries become most mobile at 1075℃ regardless of the annealing methods. Based on this finding, the possibility of producing grain oriented silicon steel without hot band annealing and nitriding treatment was shown.