Patent ID: 8562758

Claim:
A resistant to intergranular corrosion austenitic-ferritic stainless steel comprising about 0.2% or less C, 0.31% or less Si, about 2 to 3.03% Mn, about 0.1% or less P, about 0.03% or less S, about 15 to about 35% Cr, about 1% or less Ni, 0.1 to about 0.6% N, by mass, and balance of Fe and inevitable impurities, the percentage of an austenitic phase of the steel being in a range from about 10 to about 85% by volume, the amount of (C+N) in the austenite phase being, in a range of 0.38 to about 2% by mass, and having 48% or larger total elongation determined by tensile test, wherein the steel satisfies: Md(γ)=−30˜90 where, Md(γ)=551−462C(γ)−462N(γ)−9.2Si(γ)−8.1Mn(γ)—13.7Cr(γ)−18.5Mo(γ)−29Ni(γ)−29Cu(γ), and each component is of γ phase.