| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Atomistic Simulations Linked to Experiments to Understand Mechanical Behavior: A MPMD Symposium in Honor of Professor Diana Farkas
|
| Presentation Title |
Defect Trapping Mechanisms of Helical Dislocations: Insights from Anisotropic Linear Elasticity Theory |
| Author(s) |
Hadi Ghaffarian, Dongchan Jang |
| On-Site Speaker (Planned) |
Hadi Ghaffarian |
| Abstract Scope |
Helical dislocations (HDs) are unique structural defects induced by irradiation in ferritic-martensitic steels. HDs exhibit a strong ability to absorb other defects, serving as defect sinks within the microstructure. This sinking ability is primarily governed by the elastic stress field interaction between HDs and surrounding defects.
Using anisotropic linear elasticity theory, we studied the elastic stress field induced by the HDs. Our findings, confirmed by atomistic simulation, show that HDs produce significant normal stress parallel to their axis, while the other stress components are negligible. Additionally, the spatial distribution of defects surrounding the HDs was determined using the Monte-Carlo rate theory method. Our findings indicate that the interstitial dislocation loops predominantly reside within the helix core when the HDs are the vacancy-biased type, consistent with experimental observations [Haley, Acta Mater.,2019]. Conversely, interstitial-biased HDs exhibit minimal attraction to vacancy clusters or interstitial loops, explaining why their presence is not favored in experiments. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Iron and Steel, Modeling and Simulation |