Patent ID: 8048239

Claim:
A method of production of a ferritic stainless steel sheet superior in shapeability with an elongation ratio of 35% or more, r value of 1.4 or more, and Δr value of 0.4 or less, characterized by (i) producing a cold rolling material having a composition comprising, by wt %: C: 0.001 to 0.010%, Si: 0.01 to 0.3%, Mn: 0.01 to 0.3%, P: 0.01 to 0.04%, N: 0.001 to 0.020%, Cr: 10 to 20%, Nb: 0.3 to 1.0%, and Mo: 0.5 to 2.0% Having a balance of Fe and unavoidable impurities; (ii) heat treating the cold rolling material at a temperature range of 900 to 950° C. for 50 to 120 seconds so that Nb-based precipitates become, by vol %, 0.15% to 0.6% and having a diameter of 0.1 μm to 1 μm; (iii) then cold rolling; and (iv) annealing it at 1010 to 1080° C.