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Hydrogen-Induced Transformation of Dislocation Core in Fe and Its Effect on Dislocation Mobility
In this research, we employ atomistic simulations to scrutinize the impact of hydrogen (H) on dislocation mobility in iron (Fe). Our study uncovers two critical aspects: Firstly, hydrogen atoms serve to stabilize the edge dislocation core, thereby elevating the shear stress threshold needed for dislocation mobilization. Secondly, hydrogen's influence on dislocation mobility is velocity-dependent; it enhances mobility at low velocities by diminishing lattice resistance but hampers it at high velocities due to increased viscous drag. These nuanced findings illuminate the multifaceted relationship between hydrogen atoms and dislocation mechanisms. They offer valuable insights for the development of materials with enhanced mechanical properties and contribute to strategies for mitigating hydrogen-induced material degradation.
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- Award ID(s):
- 1900876
- PAR ID:
- 10534655
- Publisher / Repository:
- TMS 2024 153rd Annual Meeting & Exhibition Supplemental Proceedings (TMS 2024)
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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