PURPOSE: To inexpensively produce a ferritic free-cutting stainless steel excellent in cold workability, toughness, corrosion resistance, and machinability by applying specific hot working to a low-carbon steel stock having a specific composition containing Cr, Mo, Pb, etc.
CONSTITUTION: A steel stock which has a composition consisting of, by weight, ≤0.020% C, ≤0.30% Si, ≤0.50% Mn, ≤0.020% P, 16.0-25.0% Cr, ≤1.0% Cu, ≤1.0% Ni, ≤3.0% Mo, ≤0.010% O, ≤0.025% N, ≤0.040% (C+N), 1-20% Nb/(C+N), further one or more kinds among ≤0.20% Pb, ≤0.10% Bi, and ≤0.15% Se, and the balance Fe with impurities and containing, if necessary, 0.03-0.50% Ti and/or 0.03-0.50% Zr is subjected to hot working at ≤1000°C at ≥80% draft. By this method, the ferritic free-cutting stainless steel having superior corrosion resistance comparable to that of SuS304, less expensive than SuS304, and excellent in cold workability, toughness, and machinability can be obtained.
SHIMIZU TETSUYA
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