This work investigated the corrosion fatigue performance of 2507 duplex stainless steel for use
as riser materials in environments containing high partial pressures of carbon dioxide (50 - 100
bar) and limited quantity of hydrogen sulfide (0 - 0.12 bar). The procedures developed for
controlling oxygen and Fe2+ contamination as well as methods to evaluate the concentration of
H2S in the autoclave are presented. The crack growth rates and DKth for these materials in the
pressure environments were discussed along with procedures to obtain DKth, when they were
below 5ksiÖin. Low crack growth rates in the range of 1e-8 in/cycle were measured and the effect
of sour environments was quantified. The fatigue crack growth rate in sour environments on
2507 duplex stainless steel is a 10x higher than in air.
Key words: Corrosion fatigue, Fatigue Crack Growth Rate, 2507 Duplex Stainless Steels