| 摘要 |
PROBLEM TO BE SOLVED: To provide a grain-oriented silicon steel sheet having extremely low core loss characteristics on an industrially stable scale by stably forming secondarily recrystallized grains having <=10mm grain size. SOLUTION: This method for producing a grain-oriented silicon steel sheet is the one in which a hot strip contg., as fundamental components, <=0.1% C, 2.5 to 4.0% Si, 0.02 to 0.3% Mn, one or two kinds of S and Se by 0.001 to 0.04% in total, 0.01 to 0.065% Sol.Al and 0.003 to 0.02% N, and the balance Fe with inevitable impurities is subjected to hot strip annealing and is subjected to cold rolling for one or >= two times including process annealing so as to regulate the final cold draft to 80 to 90%, decarburizing annealing and final finish annealing. In this case, the content of AlN in the hot strip is regulated to <=25ppm as AlN, and furthermore, the strip after the final cold rolling is subjected to rapid heating treatment of executing rapid cooling to the temp. range of >=700 deg.C at a heating rate of >=80 deg.C/sec. |
