| 摘要 |
PROBLEM TO BE SOLVED: To provide a duplex phase stainless steel in which a fine crystal grain structure can be readily produced with addition of as small amounts of rare elements as possible. SOLUTION: The duplex phase stainless steel containing an austenitic phase and a ferritic phase is manufactured by: performing cold rolling with rolling reduction rate of≥80%; and subsequently performing annealing. In the obtained duplex phase stainless steel, the ferritic phase accounts for 30-60% by volume, an aspect ratio in the ferritic phase is <0.40, and grain size in the austenitic phase is≤5μm. A fine grain size in the austenitic phase can be achieved without any variation, thereby imparting excellent mechanical characteristics with high strength and high toughness. The duplex phase stainless steel preferably comprises, by mass:≤0.10% C;≤2.0% Si;≤2.0% Mn; 5.0-15.0% Ni; 16.0-28.0% Cr;≤5% Mo; if desired,≤0.20% N; and the balance being Fe and unavoidable impurities. COPYRIGHT: (C)2010,JPO&INPIT |
