| 摘要 |
PURPOSE: A method for manufacturing STS436L ferritic stainless steel having good formability by obtaining superior corrosion resistance, elongation and ridging resistance is provided. CONSTITUTION: The method for manufacturing ferritic stainless steel having superior formability comprises a step of preparing molten ferritic stainless steel comprising 0.01 wt.% or less of C, 1.0 wt.% or less of Si, 1 wt.% or less of Mn, 0.035 wt.% or less of P, 0.03 wt.% or less of S, 16 to 20 wt.% of Cr, 1 to 2 wt.% of Mo, 0.01 wt.% or less of N, 0.1 wt.% or less of Cu, 0.1 wt.% or less of Al, 0.3 wt.% or less of Ti, 0.6 wt.% or less of Nb and a balance of Fe and inevitably added impurities and satisfying below conditions: C+N<=0.017 wt.%, 10<=Nb/(C+N)+2Ti/(C+N)<=70; a step of fabricating a slab having an equiaxed crystal ratio of 30% or more in the continuous casting process using the molten steel; a step of pickling the hot rolled strip after forming a hot rolled strip by hot rolling the slab at a heating temperature of 1,200 deg.C or more and a finish rolling temperature of 900 deg.C or more; and a step of annealing the cold rolled strip at a strip temperature of 1,000 to 1,100 deg.C for 5 to 15 seconds after forming a cold rolled strip by cold rolling the pickled hot rolled strip to a cold reduction ratio of 70% or more.
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