Characteristics of Cracking Propagation During Sulfide Stress Corrosion of Hot-Rolled Duplex Stainless Steel 2205

Duplex stainless steels are generally selected for applications where resistance to corrosion is the most important criteria. Several duplex stainless steel alloys are suceptible to environmental-assisted cracking and that is the subject of this invesitgation for hot-rolled alloy 2205. Duplex stainless steels (DSSs) are generally selected due to their corrosion resistance, but several environment-assisted cracking (EACs) are related to this material. Slow strain rate tests are used to evaluate the resistance to EAC, including hydrogen embrittlement and sulfide stress corrosion cracking (SSCC). In this work, a hot-rolled DSS was tested by slow strain rate tensile testing (SSRT) in two saline solutions containing H 2 S (10 kPa (0.1 bar) of partial pressure). Two pH levels (3.5 and 4.5) were adjusted with HCl and NaOH additions. The material was brittle in both pH levels, although the density of secondary cracks at pH 4.5 was slightly lower than at pH 3.5. This work was dedicated to analyzing the fracture surface and the secondary cracks developed in the SSRT. Lines of localized deformation of ferrite and austenite were found in the specimen tested with pH 4.5. The results were compared to the behavior of previous SSRT results and SCC failures of DSS harsh conditions.