| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method where grain oriented silicon steel sheet having high magnetic flux density can be stably produced by uniformizing inhibitor strength in the sheet width direction upon secondary recrystallization annealing. <P>SOLUTION: When a grain oriented silicon steel sheet is produced through a series of stages from a slab having a composition comprising, by mass, ≤0.10% C, 2.5 to 7.0% Si, 0.01 to 0.30% Mn, 0.01 to 0.40% Cu, 0.001 to 0.050% S, 0.005 to 0.060% acid soluble Al and 0.002 to 0.015% N, and the balance Fe with inevitable impurities, the steel sheet temperature in the range from 10 to 30 mm by the distance from the edge in the sheet width direction on the outlet side of finish rolling in a hot rolling stage is controlled to 900 to 1,100°C, also, hot rolled sheet annealing is performed in a two step heat treatment cycle, the steel sheet temperature in the primary soaking is controlled to 1,000 to 1,150°C, further, the steel sheet temperature in the secondary soaking is controlled to 850 to 950°C, and the holding time in the secondary soaking temperature is controlled to 10 to 300 s. <P>COPYRIGHT: (C)2008,JPO&INPIT |
