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1. Lattice dislocation induced misfit dislocation evolution in semi-coherent {111} bimetal interfaces

   https://doi.org/10.1557/s43578-021-00184-8  

   Selimov, Alex; Xu, Shuozhi; Chen, Youping; McDowell, David (April 2021, Journal of Materials Research)

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2. Hydrogen-Induced Transformation of Dislocation Core in Fe and Its Effect on Dislocation Mobility

   Hasan, Md Shahrier; Bayat, Hadia; Delaney, Colin; Foronda, Christopher; Xu, Wenwu (February 2024, TMS 2024 153rd Annual Meeting & Exhibition Supplemental Proceedings (TMS 2024))

   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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3. One dislocation at a time

   https://doi.org/10.1038/s41563-023-01555-8  

   Bulatov, Vasily; Cai, Wei (June 2023, Nature Materials)

   The direct observation of enhanced dislocation mobility in iron by in situ electron microscopy offers key insights and adds to the ongoing debate on the mechanisms of hydrogen embrittlement. 

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4. Computational 3-dimensional dislocation elastodynamics

   https://doi.org/10.1016/j.jmps.2019.02.008  

   Cui, Yinan; Po, Giacomo; Pellegrini, Yves-Patrick; Lazar, Markus; Ghoniem, Nasr (May 2019, Journal of the Mechanics and Physics of Solids)
5. Computational 3-dimensional dislocation elastodynamics

   https://doi.org/10.1016/j.jmps.2019.02.008  

   Cui, Yinan; Po, Giacomo; Pellegrini, Yves-Patrick; Lazar, Markus; Ghoniem, Nasr (February 2019, Journal of the mechanics and physics of solids)

   Understanding the mechanical behavior of solids at extremely high strain rates is of great scientific and technical interest. Current dislocation-based model of plasticity are typically implemented as quasi-static method. Their applicability to high strain rate condition is limited, because the influence of the elastodynamic stress field at extreme strain rates on the collective behavior of 3-dimensional (3D) dislocations is not clear, and the time-dependent nature is very important when the strain rate is higher than 1e6 /s (e.g. laser shock loading). To overcome this limitation, we present here the first computational procedure for 3D discrete dislocation elastodynamics (DDE). A novel computational method is developed for calculations of the fully-resolved elastodynamic field of non-uniformly moving dislocation loops. The developed method here extends the technique of retarded potentials, which was originally used to describe the electrodynamics of charged particles moving near the speed of light. Comparison with independent 2D calculations establish the accuracy and convergence of the numerical scheme. It is shown that dislocation loop motion near the sound speed results in significant restructuring of the emitted elastodynamic fields. New insights on short-time dislocation interactions during shock loading are also revealed through a study of the forces between rapidly-moving shear dislocation loops. 

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