About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Fundamentals of Sustainable Metallurgy and Processing of Materials
|
| Presentation Title |
Atomic-level coupling of mechanical and chemical driving forces in sustainable iron production |
| Author(s) |
Yifan Wang, Yuzhe Li, Xiaolin Zheng, Leora Dresselhaus-Marais |
| On-Site Speaker (Planned) |
Yifan Wang |
| Abstract Scope |
Replacing coal-based ironmaking with hydrogen direct-reduced iron is essential for decarbonizing steel, yet its performance remains erratic because the wüstite-to-iron step triggers severe lattice shrinkage and unpredictable surface area. The atomic origins of this morphology have not been resolved. Here we combine in-situ environmental TEM with atomistic modelling. 8nm Fe₃O₄ nanoparticles were reduced inside ETEM, revealing nucleation of α-Fe and its stress-driven propagation. Molecular-dynamics and free-energy calculations show that anisotropic oxygen diffusion in wüstite builds internal stress that induces defects in iron nucleus, which causes the shape changes recorded experimentally. Calculated interface motion and facet selection are compared with ETEM observations, confirming that the lattice contraction dictates micro-scale morphology. This multiscale picture links crystallography to porosity which is essential for understanding the kinetics of solid-gas iron ore reduction. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Iron and Steel, Modeling and Simulation, Phase Transformations |