| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a non-oriented silicon steel sheet which is suitable for producing a high-performance automobile generator or motor for driving of an electric automobile, and to provide its production method. <P>SOLUTION: This non-oriented silicon steel sheet has a sheet thickness of 0.15 to 0.4 mm, and has a steel composition comprising >1.7 to 3.0% Si, 0.1 to 1.5% Mn, 0.1 to 2.0% sol.Al and 0.005 to 0.20% P, and in which, as magnetic properties, the relation satisfying the inequality (1) is valid between core loss W<SB>10/400</SB>(W/kg) and magnetic flux density B<SB>50</SB>(T) at 50Hz, and [B<SB>1(1k)</SB>/B<SB>1(400)</SB>], i.e., the ratio between a magnetic flux density at 400 Hz in a magnetizing force of 100 A/m, B<SB>1(400)</SB>(T) and a magnetic flux density at 1 kHz, B1<SB>(1k)</SB>(T) is ≥0.45. In the production method for the automobile nonoriented silicon steel sheet, a hot rolled sheet is subjected to box annealing so that, provided that the content of P in the steel is defined as P(%), and a draft in cold rolling as R(%), the crystal grain diameter D(μm) before the cold rolling lies within the range of the inequality (2): B<SB>50</SB>≥0.006×W<SB>10/400</SB>+1.60 (1), and 5×R-500×P-325≤D≤5×R-500×P-250 (2). <P>COPYRIGHT: (C)2004,JPO&NCIPI |
