| 摘要 |
PROBLEM TO BE SOLVED: To improve magnetic properties particularly in L-direction and C- direction by applying hot roughing to a steel slab containing specific amounts of Si, performing hot finish rolling under specific conditions to form a specific steel structure, forming recrystallized structure in this state or, if necessary, by means of hot rolled plate annealing, and successively carrying out cold rolling and annealing. SOLUTION: This steel slab contains <=4.0 wt.% Si. In the hot finish rolling, the steel plate temperature when entering a finishing mill is not higher than the Ar1 transformation point and between 900 and 500 deg.C for a steel having a composition that forms austenitic phase and is between 900 and 500 deg.C for a steel having a composition that does not form austenitic phase. The total draft at the hot finish rolling is regulated to 70-<90%. Further, the average interlamellar spacing of unrecrystallized extended ferrite grains in the steel plate on the delivery side of the final stand of the finishing mill is made to >=250 μm. |
