PURPOSE: To provide a method for producing a bidirectional silicon steel sheet excellent in magnetic properties.
CONSTITUTION: The hot rolled sheet stock of a silicon steel sheet contg. 0.3 to 6.2% Si is subjected to cross cold rolling at 50 to 300% spreading rate by using a planetary rolling mill 5 provided with a curved surface die 2 with a curved surface projection part and is thereafter subjected to annealing in the purpose of primary recrystallization and then final annealing in the purpose of secondary recrystallization and purification. Before or after the cross cold rolling, a stage of executing ordinary cold rolling may be added. Anytime in the case of the same cold rolling, the stock is preferably heated to 100 to 200°C. Furthermore, prior to the cross cold rolling, annealing may be executed. Thus, the bidirectional silicon steel sheet excellent in orientative properties can stably be produced. Moreover, continuous rolling and rolling in the width direction can simultaneously be executed by using coil stock, and this method is efficient and excellent as an industrial mass-producing method.
TOMIZAWA ATSUSHI
TANAKA TAKASHI
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