PROBLEM TO BE SOLVED: To provide a high-nitrogen austenitic stainless steel having both seawater corrosion resistance equivalent to that of an austenitic super stainless steel and high strength equivalent to that of a two-phase stainless steel.SOLUTION: The high-nitrogen austenitic stainless steel comprises 0.005 to 0.25 mass% C, 15.0 to 35.0 mass% Cr, 0.2 to 10.0 mass% Mn, 0.05 to 8.0 mass% Mo, 0.01 to 4.0 mass% Cu, 0.01 to 5.0 mass% Ni, more than 0.8 to 1.8 mass% N, 2.0 mass% or less Si, 0.03 mass% or less P, 0.05 mass% or less S, 0.030 mass% or less Al, 0.020 mass% or less O, and the balance substantially being Fe and unavoidable impurities and has PRE value of 5 or larger, where PRE=(Cr+3.3Mo+16N)/Mn (mass%), and CRE value of 27 or larger, where CRE=Cr+1.5Mo+2N+Cu (mass%).COPYRIGHT: (C)2007,JPO&INPIT【課題】オーステナイト系スーパーステンレス鋼に匹敵する耐海水腐食性と、2相ステンレス鋼に匹敵する高い強度を併せ持つ高窒素オーステナイト系ステンレス鋼を提供すること。【解決手段】0.005mass%≦C≦0.25mass%、15.0mass%≦Cr≦35.0mass%、0.2mass%
