TWO-PHASE STAINLESS STEEL HAVING EXCELLENT CORROSION RESISTANCE AND HYDROGEN BRITTLENESS RESISTANCE

To provide two-phase stainless steel having excellent corrosion resistance and hydrogen brittleness resistance, at a low cost.SOLUTION: Two-phase stainless steel having excellent corrosion resistance and hydrogen brittleness resistance has a structure having a chemical composition that contains, in mass%, C: 0.05% or less, Si: 0.03-1.0%, Mn: 0.05-2.0%, P: 0.05% or less, S: 0.005% or less, Cr: 17.0-26.0%, Ni: 7.0-19.0%, Mo: 0.1-6.0%, Co: 0.01-2.0%, and Sb: 0.005-0.5% with the balance being Fe and inevitable impurities, and comprising at least a ferrite phase and an austenite phase, with the austenite phase having a volume fraction of 45-95%.SELECTED DRAWING: None 【課題】優れた耐食性と耐水素脆化とを有する二相ステンレス鋼を、低コストで提供する。【解決手段】質量％で、Ｃ：０．０５％以下、Ｓｉ：０．０３〜１．０％、Ｍｎ：０．０５〜２．０％、Ｐ：０．０５％以下、Ｓ：０．００５％以下、Ｃｒ：１７．０〜２６．０％、Ｎｉ：７．０〜１９．０％、Ｍｏ：０．１〜６．０％、Ｃｏ：０．０１〜２．０％、およびＳｂ：０．００５〜０．５％を含有し、残部がＦｅおよび不可避的不純物からなる成分組成を有し、少なくともフェライト相とオーステナイト相からなり、オーステナイト相の体積分率が４５〜９５％である組織を有する、耐食性及び耐水素脆性に優れた二相ステンレス鋼。【選択図】 なし