| 摘要 |
PURPOSE:To produce a cold-rolled nondirectional magnetic steel sheet of superion iron loss characteristic by hot-rolling a slab of a steel contg. <3.5% Si, and others such as Mn and Al then subjecting the same to cold rolling of once or twice or more to make a steel sheet of specific surface roughness then subjecting the steel sheet to final finish annealing. CONSTITUTION:A steel slab contg. Mn, Al, etc. besides <3.5% Si is hot-rolled, after which cold rolling of once or twice or more including intermediate annealing is applied to work it to a sheet material. In this case, the roughness of the work rolls of cold rolling mills are made small to smooth the steel sheet surfaces and make the average roughness of the steel sheet surface upon ending of the rolling <=0.4mum. Next, the steel sheet is subjected to final finish annealing, whereby the nondirectional magnetic steel sheet of improved iron loss characteristic is produced. |
