To evaluate the effects of manufacturing method and contents of afloying elements on sulfide stress cracking (SSC) behavior, powder metallurgically (PM) produced and wrought super austenitic stainless steels (UNS S32654) and nickel-base alloy UNS N06625 (PM) were studied in high temperature H2S solutions by using slow strain rate tests (SSRT). Attention was paid also to the effects of strain rate on SSC susceptibility of the studied stainless steels. The testing environments were selected based on the proposed, but not yet approved NACE standard test method. According to the SSRT results the studied super austenitic stainless steels
showed brittle fracture behavior in all of the studied aggressive H2S solutions. The partial pressures of hydrogen sulfide and carbon dioxide used were over 14 bar. The studied nickel-base alloy was not susceptible to SSC even in H2S solution when the partial pressure of H2S was 70 bar and the partial pressure of CO2 was 50 bar.
Keywords: Stainless steel, nickel-base alloy, corrosion, stress corrosion, cracking (fracturing), petrochemical environments, oil fields, hydrogen sulfide