| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Iron-rich Microstructures in Post-Detonation Nuclear Debris |
| Author(s) |
Timothy Genda, Kim Knight, Zurong Dai, Bethany Goldblum, Peter Hosemann |
| On-Site Speaker (Planned) |
Timothy Genda |
| Abstract Scope |
The formation of radioactive fallout in nuclear detonations depends on the composition and thermal histories of the fireball, but the extent to which environmental materials impact formation processes is not fully understood. To investigate the impact of high iron content on fallout formation, we have analyzed previously unobserved iron-rich microstructures preserved in rapidly-quenched (seconds to minutes) mm-scale glassy fallout from a historical U.S. nuclear test. Autoradiography reveals correlations between long-lived radioactive species and iron rich (>30 wt%) rims where these microstructures are preserved. BSED and EDX characterization reveals a wide variety of crystalline dendritic features and textural evidence of liquid-liquid immiscibility, including 2-20 µm core/shell ‘amoeboids’ which resemble microstructures observed in microgravity immiscible alloy experiments, but have never been observed in silicate systems. Understanding how these microstructures evolved may provide novel means to constrain fallout formation conditions in an Fe-rich environment, informing improvements to first-principles based nuclear fallout formation models. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |