Understanding passive film degradation and its effect on hydrogen embrittlement of super duplex stainless steel – Synchrotron X-ray and electrochemical measurements combined with CalPhaD and ab-initio computational studies
(2023) In Applied Surface Science 628.- Abstract
The passive film stability on stainless steel can be affected by hydrogen absorption and lead to microstructure embrittlement. This work shows that the absorption of hydrogen results in surface degradation due to oxide reduction and ionic defect generation within the passive film, which decomposes and eventually vanishes. The passive film provides a barrier to entering hydrogen, but when hydrogen is formed, atomic hydrogen infuses into the lattices of the austenite and ferrite phases, causing strain evolution, as shown by synchrotron x-ray diffraction data. The vacancy concentration and hence the strains increase with increasing electrochemical cathodic polarization. Under cathodic polarization, the surface oxides are thermodynamically... (More)
The passive film stability on stainless steel can be affected by hydrogen absorption and lead to microstructure embrittlement. This work shows that the absorption of hydrogen results in surface degradation due to oxide reduction and ionic defect generation within the passive film, which decomposes and eventually vanishes. The passive film provides a barrier to entering hydrogen, but when hydrogen is formed, atomic hydrogen infuses into the lattices of the austenite and ferrite phases, causing strain evolution, as shown by synchrotron x-ray diffraction data. The vacancy concentration and hence the strains increase with increasing electrochemical cathodic polarization. Under cathodic polarization, the surface oxides are thermodynamically unstable, but the complete reduction is kinetically restrained. As a result, surface oxides remain present under excessive cathodic polarization, contesting the classical assumption that oxides are easily removed. Density-functional theory calculations have shown that the degradation of the passive film is a reduction sequence of iron and chromium oxide, which causes thinning and change of the semiconductor properties of the passive film from n-type to p-type. As a result, the surface loses its passivity after long cathodic polarization and becomes only a weak barrier to hydrogen absorption and hence hydrogen embrittlement.
(Less)
- author
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Ab-initio density-functional theory, Cathodic polarization, FactSage thermodynamics, Hydrogen embrittlement, Passive film, Super duplex stainless steel
- in
- Applied Surface Science
- volume
- 628
- article number
- 157364
- publisher
- Elsevier
- external identifiers
-
- scopus:85154018679
- ISSN
- 0169-4332
- DOI
- 10.1016/j.apsusc.2023.157364
- language
- English
- LU publication?
- yes
- id
- eb8fe264-2028-4b2a-9e32-7fae18b0200c
- date added to LUP
- 2023-06-20 12:40:08
- date last changed
- 2023-11-08 07:06:35
@article{eb8fe264-2028-4b2a-9e32-7fae18b0200c, abstract = {{<p>The passive film stability on stainless steel can be affected by hydrogen absorption and lead to microstructure embrittlement. This work shows that the absorption of hydrogen results in surface degradation due to oxide reduction and ionic defect generation within the passive film, which decomposes and eventually vanishes. The passive film provides a barrier to entering hydrogen, but when hydrogen is formed, atomic hydrogen infuses into the lattices of the austenite and ferrite phases, causing strain evolution, as shown by synchrotron x-ray diffraction data. The vacancy concentration and hence the strains increase with increasing electrochemical cathodic polarization. Under cathodic polarization, the surface oxides are thermodynamically unstable, but the complete reduction is kinetically restrained. As a result, surface oxides remain present under excessive cathodic polarization, contesting the classical assumption that oxides are easily removed. Density-functional theory calculations have shown that the degradation of the passive film is a reduction sequence of iron and chromium oxide, which causes thinning and change of the semiconductor properties of the passive film from n-type to p-type. As a result, the surface loses its passivity after long cathodic polarization and becomes only a weak barrier to hydrogen absorption and hence hydrogen embrittlement.</p>}}, author = {{Örnek, Cem and Zhang, Fan and Larsson, Alfred and Mansoor, Mubashir and Harlow, Gary S. and Kroll, Robin and Carlà, Francesco and Hussain, Hadeel and Engelberg, Dirk L. and Derin, Bora and Pan, Jinshan}}, issn = {{0169-4332}}, keywords = {{Ab-initio density-functional theory; Cathodic polarization; FactSage thermodynamics; Hydrogen embrittlement; Passive film; Super duplex stainless steel}}, language = {{eng}}, publisher = {{Elsevier}}, series = {{Applied Surface Science}}, title = {{Understanding passive film degradation and its effect on hydrogen embrittlement of super duplex stainless steel – Synchrotron X-ray and electrochemical measurements combined with CalPhaD and ab-initio computational studies}}, url = {{http://dx.doi.org/10.1016/j.apsusc.2023.157364}}, doi = {{10.1016/j.apsusc.2023.157364}}, volume = {{628}}, year = {{2023}}, }