About this Abstract |
Meeting |
2023 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 Secondary Cracks in Hydrogen Embrittlement |
Author(s) |
Andrew C. Lee, Abhinav Parakh, Wendy Gu |
On-Site Speaker (Planned) |
Andrew C. Lee |
Abstract Scope |
Hydrogen embrittlement of existing ferritic steel transmission pipelines imposes significant limitations for the safe and cost-effective transport of hydrogen. While post-failure fractography has been the dominate method of analysis, in-situ imaging of crack propagation and microstructural evolution provides novel insight to a mechanistic understanding of hydrogen embrittlement. In this work, we use a custom strain stage coupled with in-situ X-ray microscopy to image dynamic crack propagation and the transition from quasi-cleavage to intergranular fracture in iron films charged with hydrogen. In the quasi-cleavage regime, we observe multiple sharp crack-fronts propagating simultaneously and the formation of nanoscale voids in front of the crack. In the intergranular regime, we observe blunting of the crack tip and significant secondary cracking. We discuss the role of hydrogen in increased nucleation and growth of secondary cracks throughout deformation and their role in the transition to intergranular failure, including strain-field interactions and effect on hydrogen concentration. |
Proceedings Inclusion? |
Planned: |
Keywords |
Environmental Effects, Iron and Steel, Mechanical Properties |