| 摘要 |
PROBLEM TO BE SOLVED: To provide steel for forced cold working, which has excellent cold workability on forced cold working at a working ratio of >=80% without performing process annealing. SOLUTION: A steel stock having a composition containing <=0.0020% C, <=0.04% Si, <=0.04% Mn, <=0.005% P, <=0.04% Al, and <=0.005% N, and the balance Fe with inevitable impurities is subjected to hot working where at least final hot working is performed at the total working ratio of >=50% in the temperature range of 800 deg.C to an Ar1 transformation point. After the hot working, air cooling is performed thereto, so that the steel having a structure consisting of a ferritic phase having a mean ferritic grain diameter of <=20μm is obtained.
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