LOW CORE LOSS NONORIENTED SILICON STEEL SHEET AND ITS PRODUCTION

摘要

PURPOSE: To stably produce a nonoriented silicon steel sheet low in core loss by preparing a nonoriented silicon steel sheet in which the componental compsn. is limited and the volume fractional rates of sulfide inclusions by sizes are specified. ;CONSTITUTION: A steel having a compsn. contg., by weight, ≤0.01% C, 2.5 to 5.0% Si and 0.1 to 1.5% Mn, in which the contents of O, N and S are respectively suppressed to ≤0.0030% S, ≤0.0030% N and ≤0.020% O, and the balance Fe with inevitable impurities is prepd. At this time, among sulfides in the steel, the total ratio of Zr sulfides, Mn sulfides, [Zr-Mn] multiple sulfides and the ones in which the same sulfides are combined with the nitrides or oxides of Al is regulated to ≥80vol.% to all sulfides, and the ratio of ones with 1μm particle diameter among the same sulfides is regulated to ≤20vol.% to all sulfides. Thus, the nonoriented silicon steel sheet low in core loss can be obtd.;COPYRIGHT: (C)1996,JPO