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

Summary, in English

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.

• Author: Cem Örnek; Mubashir Mansoor; Alfred Larsson; Fan Zhang; Gary S. Harlow; Robin Kroll; Francesco Carlà; Hadeel Hussain; Bora Derin; Ulf Kivisäkk; Dirk L. Engelberg; Edvin Lundgren; Jinshan Pan
• Department/s: LU Profile Area: Light and Materials; LTH Profile Area: Nanoscience and Semiconductor Technology; Synchrotron Radiation Research; NanoLund: Centre for Nanoscience; MAX IV Laboratory; LTH Profile Area: Photon Science and Technology
• Publishing year: 2023
• Language: English
• Publication/Series: Corrosion Science
• Volume: 217
• Links: http://dx.doi.org/10.1016/j.corsci.2023.111140
• Document type: Journal article
• Publisher: Elsevier
• Topic: Metallurgy and Metallic Materials
• Keywords: Density-functional theory; FactSage; High-energy X-ray diffraction; Hydride; Hydrogen embrittlement; Super duplex stainless steel
• Status: Published
• ISBN/ISSN/Other: ISSN: 0010-938X