The causation of hydrogen embrittlement of duplex stainless steel: Phase instability of the austenite phase and ductile-to-brittle transition of the ferrite phase – Synergy between experiments and modelling

Örnek C., Mansoor M., Larsson A., Zhang F., Harlow G. S., Kroll R., ...More

Corrosion Science, vol.217, 2023 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 217
  • Publication Date: 2023
  • Doi Number: 10.1016/j.corsci.2023.111140
  • Journal Name: Corrosion Science
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Applied Science & Technology Source, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Computer & Applied Sciences, Environment Index, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: Density-functional theory, FactSage, High-energy X-ray diffraction, Hydride, Hydrogen embrittlement, Super duplex stainless steel
  • Istanbul Technical University Affiliated: Yes

Abstract

Various mechanisms have been proposed for hydrogen embrittlement of duplex stainless steel, but the causation of hydrogen-induced material degradation has remained unclear. This work shows that phase instability (decomposition) of the austenite phase and ductile-to-brittle transition of the ferrite phase precedes hydrogen embrittlement. In-situ diffraction measurements revealed that Ni-rich sites of the austenite phase decompose into metastable hydrides. Hydride formation is possible by increasing the hydrogen chemical potential during electrochemical charging and low defect formation energy of hydrogen interstitials. Our findings demonstrate that hydrogen embrittlement can only be understood if measured in situ and in real-time during the embrittlement process.