| 摘要 |
PURPOSE: A preparation method of the high flux density directed electric steel plates having the good film characteristics is provided to get rid of the deviation of the nitrated amount involved inevitably in the nitration using the ammonia gas while forming a stable inhibitor. CONSTITUTION: The preparation method of the high flux density directed electric steel plates having the good film characteristics comprising hot rolling by reheating slabs composed of not more than 0.1 wt.% of C, 1.0 to 4.8 wt.% of Si, 0.010 to 0.05 wt.% of Al, 0.05 to 0.2 wt.% of Mn, not more than 100 ppm of N, not more than 0.01 wt.% of S and the balance of Fe and the other inevitable impurities, precipitation annealing, followed by pickling, cold rolling, decarbonization annealing, spreading the annealing separation agent, and then high temperature annealing wherein a nitration process by the ammonia gas in a certain process among the processes or an additional nitration process is carried out, is characterized in that the hydrogen atmosphere of at least 90% is formed at the temperature range of 800 to 900 deg.C in the high temperature annealing.
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