METHOD OF PRODUCING GRAIN ORIENTED SILICON STEEL SHEET HAVING HIGH MAGNETIC FLUX DENSITY AND LOW CORE LOSS

摘要

PROBLEM TO BE SOLVED: To provide a production method for advantageously obtaining a grain oriented silicon steel sheet which has a sufficiently high magnetic flux density, and a low core loss even when produced without using inhibitors.;SOLUTION: A slab produced by using a molten steel containing, by mass, ≤0.08% C, 2.0 to 8.0% Si, and 0.005 to 3.0% Mn is hot-rolled, and, is, if required, subjected to hot rolled sheet annealing. Subsequently, the steel sheet is subjected to cold rolling for one time or for two or more times including process annealing. The steel sheet is then subjected to continuous annealing so as to be subjected to recrystallization annealing in a low-oxidizing or nonoxidizing atmosphere to control the content of C after the recrystallization annealing to the range of 0.005 to 0.025%, and to be subjected to secondary recrystallization annealing, and to be subjected to decarburizing annealing in a humid atmosphere, and to be resided in the temperature region of ≥800°C for at least 10 sec in a low-oxidizing or nonoxidizing atmosphere.;COPYRIGHT: (C)2003,JPO