Method for predicting primary recrystallization texture and method for producing directional electromagnetic steel sheet

摘要

PROBLEM TO BE SOLVED: To provide a method for estimating the texture of a primary recrystallized annealed steel sheet, and a method for manufacturing a grain oriented electrical steel sheet using the method.SOLUTION: A method for manufacturing a grain oriented electrical steel sheet includes the consecutive steps of hot rolling, cold rolling, and primary recrystallized annealing or primary recrystallized annealing also serving as decarbonization annealing of a steel raw material including 0.002 to 0.10 mass% of C, 2.0 to 8.0 mass% of Si, and 0.005 to 1.0 mass% of Mn, and the subsequent steps of applying an annealing separation agent to the surface of the steel sheet, and finish annealing. In the method, the magnetic properties of the steel sheet after the primary recrystallized annealing are measured for various magnetization directions to the rolling direction and various magnetizing force. From the measurement results, the texture of the steel sheet after the primary recrystallized annealing is estimated. The rate of temperature rise between 500 to 700°C in the heating process of the primary recrystallized annealing is controlled such that the estimated texture falls in the specified target range. Consequently a grain oriented electrical steel sheet having a low iron loss with no variation can be obtained.