| About this Abstract |
| Meeting |
TMS Specialty Congress 2025
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| Symposium
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The 7th International Congress on 3D Materials Science (3DMS 2025)
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| Presentation Title |
Reconciling Conflicting Hydrogen Embrittlement Models Using Dark-Field X-Ray Microscopy |
| Author(s) |
Dayeeta Pal, Can Yildirim, Leora Dresselhaus-Marais |
| On-Site Speaker (Planned) |
Dayeeta Pal |
| Abstract Scope |
Despite 150 years of research, the fundamental mechanisms of hydrogen (H) embrittlement are poorly understood. H atoms form a solid solution of interstitial defects in metals, altering dislocation behavior. While dislocations are essential to understand metal plasticity, it is unclear whether H enhances dislocation mobility (Hydrogen Enhanced Localized Plasticity-HELP) or reduces it (Solute Drag Theory-SDT), with no technique being able to image subsurface dislocations. Time-resolved and 3D dark-field X-ray microscopy (DFXM) has been developed to study interactions of large populations of subsurface dislocations. Since hydrogen shielding effect (HSE) is the key mechanism that explains the increased dislocation mobility in the presence of H, our work uses DFXM to generate 3D maps of dislocations, illustrating which dislocations obey the HSE mechanisms in uncharged and H-pre-charged single crystal FCC-austenitic stainless steel. We support these results with DFXM simulations and HSE models, offering the first direct measurements to reconcile conflicting H-altered mobility models.
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| Proceedings Inclusion? |
Undecided |