About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
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Materials Systems for the Future of Fusion Energy
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Presentation Title |
Modelling and Experimental Study of Yttrium Segregation in Smart Alloys as Plasma Facing Materials |
Author(s) |
Duc Nguyen-Manh, Damian Sobieraj, Jan S. Wrobel, Mark Gilbert, Joven Lim, Ivan Povstugar, Felix Klein, Andrey Litnovsky |
On-Site Speaker (Planned) |
Duc Nguyen-Manh |
Abstract Scope |
Self-passivating Metal Alloys with Reduced Thermo-oxidation (SMART) are under development as plasma-facing materials of the first wall in DEMO fusion device. The present SMART materials consist of tungsten, chromium as a passivating element and yttrium as the so-called active element. The phase stability and short-range order (SRO) of ternary alloys in W-Cr-Y systems have been investigated, using a combination of Density Functional Theory and Cluster Expansion methods with Monte-Carlo simulations. Our results showed that alloying yttrium with a concentration within 0.5-2.0 at.% into W-Cr alloys reveals positive SRO parameters for W-Y and Cr-Y pairs implying that yttrium tends to segregate from both W and Cr in the alloys. It is found that in the presence of yttrium, the predicted solid solution temperature is 400K lower than that of the binary 70W-30Cr. The role of yttrium in stabilizing the microstructure and improving the self-passivating capability is under experimental and modelling investigation. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, Nuclear Materials, Characterization |