Hydrogen trapping and embrittlement of titanium- and vanadium carbide-containing steels after high-temperature hydrogen charging

Journal article (2024)

Authors

T. Boot Team Vera Popovich - Mechanical, Maritime and Materials Engineering
Athira Suresh Kumar Luxembourg Institute of Science and Technology, University of Luxembourg
Santhana Eswara Luxembourg Institute of Science and Technology
Pascal Kömmelt Tata Steel Europe Limited
A.J. Bottger Team Amarante Bottger - Mechanical, Maritime and Materials Engineering
V. Popovich Team Vera Popovich - Mechanical, Maritime and Materials Engineering
Research Group
Team Vera Popovich (Mechanical, Maritime and Materials Engineering) (TU Delft)
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Published Date

2024

Language

English

Faculty

Mechanical, Maritime and Materials Engineering

Department

Materials Science and Engineering

Research Group

Team Vera Popovich

Abstract

Abstract: This work studies the effect of TiC and VC precipitate sizes on hydrogen trapping and embrittlement. Two experimental ferritic HSLA steels containing either TiC or VC carbides for precipitation strengthening are annealed in nitrogen and hydrogen gas. This results in a hydrogen uptake of up to 0.91 and 0.44 wppm in the TiC and VC steels, respectively. TEM and TDS analysis indicate that semi-coherent TiC particles trap hydrogen in misfit dislocations with an activation energy of 43 kJ/mol. Coherent VC particles are suggested to trap hydrogen in interface carbon vacancies, with an energy between 53 and 72 kJ/mol. Carbon vacancies are the likely trapping site in incoherent precipitates, where SIMS imaging confirms that incoherent TiC precipitates trap preferentially near the interface, whereas incoherent VC precipitates trap throughout their bulk. Neither alloy is embrittled in SSRT tests after hydrogen absorption, which shows that these precipitates can be used as both a hydrogen sink and a strengthening mechanism in steels. Graphical abstract: (Figure presented.)