About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Use of Large Scale Facilities to Understand the Physical Metallurgy of Fe-based Alloys
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| Presentation Title |
Precipitation Kinetics and Chemistry Evolution of Oxide Dispersion Strengthened Steels throughout their Consolidation Process Evaluated by In-situ Anomalous Small-angle X-ray Scattering |
| Author(s) |
Gabriel Spartacus, Joël Malaplate, Frédéric De Geuser, Denis Sornin, Alexis Deschamps |
| On-Site Speaker (Planned) |
Gabriel Spartacus |
| Abstract Scope |
Oxide Dispersion Strengthened (ODS) steels are candidate for nuclear reactor applications. ODS steels are made by powder metallurgy processes involving ball milling of Fe-Cr, Y2O3 and TiH2 powders to dissolve Y, Ti and O into the matrix. These species precipitate as Y-Ti-O nano-oxides during the subsequent high temperature consolidation at 1100°C.
Acquiring experimental data on the precipitation kinetics and chemical evolution is invaluable to further control and optimize the elaboration. For this purpose, we have performed in-situ observations up to 1100°C on cold-compressed powders during heat treatments representative of the real process route, using synchrotron anomalous small angle x-ray scattering. These measurements elucidate the precipitation kinetic path showing a coarsening start around 400°C, as well as a chemical and structural shift near 800°C probably linked to the precipitates transformation from non-stoichiometric clusters to Y2Ti2O7 pyrochlore. These oxides show outstanding stability with almost no ripening even after 12 hours at 1100°C. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |