TWO-PHASE STAINLESS STEEL EXCELLENT IN CORROSION RESISTANCE AND HYDROGEN EMBRITTLEMENT RESISTANCE

To provide, at low cost, a two-phase stainless steel excellent in corrosion resistance and hydrogen embrittlement resistance.SOLUTION: The two-phase stainless steel excellent in corrosion resistance and hydrogen embrittlement resistance has a component composition comprising, in percentages by mass, C of 0.05% or less, Si of 0.03 to 1.0%, Mn of 0.05 to 2.0%, P of 0.05% or less, S of 0.005% or less, Cr of 17.0 to 28.0%, Ni of 4.0 to 18.0%, Mo of 0.1 to 6.0%, B of 0.031 to 0.49%, and N of 0.005% or less, with the balance consisting of Fe and inevitable impurities; and has a structure comprising at least a ferrite phase and an austenite phase, with the volume fraction of the austenite phase being 45 to 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：１７．０〜２８．０％、Ｎｉ：４．０〜１８．０％、Ｍｏ：０．１〜６．０％、Ｂ：０．０３１〜０．４９％、およびＮ：０．００５％以下を含有し、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