Superduplex stainless steel having high corrosion resistance and high yield strength in the solution annealed condition

摘要

The steel, object of our invention is highly resistant to stress corrosion in acid and alkaline environment, and has furthermore high pitting and crevice corrosion resistance. This steel has a very high yield strength, even in the solution annealed condition.;The steel consists of: (in weight percent)C   0.025 maxMn   0.80 maxSi   0.80 maxCr   24 - 26Ni   6.5 - 8.0Mo   3.0 - 4.0Cu   1.2 - 2.0W   0.8 - 1.2N   0.23 - 0.33S   0.002 maxP   0.025 maxFe   balancewith the proviso: Pitting Index = Cr + 3.3 Mo + 16N 42