| 摘要 |
<p>PURPOSE: A steel sheet and a manufacturing method thereof are provided to reduce the formation of solid nitrogen in steel even if the content of nitrogen is over 40ppm by adding boron. CONSTITUTION: A method for manufacturing a steel sheet comprises the steps of: reheating a slab panel, which comprises 0.040-0.065 wt% of C, 0.002-0.010 wt% of Si, 0.3-0.6 wt% of Mn, 0.010 wt% or less of P, 0.010 wt% or less of S, 0.030-0.060 wt% of sol-Al, 0.002-0.007 wt% of B, 50-80 ppm of N, and the remaining comprising Fe and inevitable impurities(S110); hot rolling the reheated panel(S120); and cooling and coiling the hot-rolled panel(S130). [Reference numerals] (AA) Start; (BB) End; (S110) Reheating slab; (S120) Hot rolling; (S130) Cooling/coiling; (S140) Cold rolling; (S150) Annealing</p> |
