About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Mechanical Response of Materials Investigated Through Novel In-Situ Experiments and Modeling
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Presentation Title |
Transmission X-ray Microscopy Reveals Role of Voids in Hydrogen Embrittlement |
Author(s) |
Andrew C. Lee, Abhinav Parakh, Wendy Gu |
On-Site Speaker (Planned) |
Andrew C. Lee |
Abstract Scope |
Hydrogen embrittlement of steel transmission pipelines remains a barrier to widespread adoption of hydrogen as a carbon-neutral energy source. Despite nearly a century of research, a connection between atomic scale embrittlement mechanisms and macroscale material behavior has eluded the field. In this work, we use in-situ transmission x-ray microscopy, digital image correlation, and micromechanical testing to connect microstructural differences to fracture behavior in iron and nickel thin-films exposed to hydrogen environments. We systematically examine the effect of grain size and hydrogen concentration on surface and sub-surface void distributions, strain-field development, and mechanical properties. While free hydrogen in the lattice inhibits formation of micron-sized voids across all samples and causes strain localization, smaller grain sizes and increase in density of hydrogen trap sites enhances the role of trapped hydrogen in fracture. This discontinuous transition in void distribution implies a change in mechanistic embrittlement regimes with changing microstructure. |
Proceedings Inclusion? |
Planned: |
Keywords |
Environmental Effects, Iron and Steel, |