| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of production of a nonoriented silicon steel sheet used for an iron core material for electrical equipment and having high magnetic flux density and low iron loss. SOLUTION: This nonoriented silicon steel sheet having high magnetic flux density and low iron loss is produced by subjecting a slab, having a steel composition consisting of, by weight, 2.0-4.5% (S+2Al), 0.1-1.0% Mn, <=0.0050% C, <=0.0050% N, <=0.0050% S, and the balance Fe with inevitable impurity components, to hot rolling, applying acid pickling to the resultant hot rolled plate, performing cold rolling once, and applying finish annealing to the resultant sheet. At this time, coiling conditions for a sheet bar after roughing is determined by inequality 1.20<=log(ωd/R)+2<=4.00 [where (ω) is rotational speed (rpm) of sheet bar coiling, (d) is thickness (mm) of sheet bar, and (R) is coiling radius (mm)]; hot rolling finishing temp. T( deg.C), by inequality 950<=T( deg.C)<=1150; and time (t) (sec) without water pouring, by inequality 9.6-8×10<-3> T<=t(sec)<=15.6-8×10<-3> T. |
