About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
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Radiation Effects in Metals and Ceramics
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Presentation Title |
Irradiation Effects in Weld Repairs of Irradiated Stainless Steel |
Author(s) |
Janelle P. Wharry, Keyou S Mao, Emmanuel Perez, Yaqiao Wu, Aaron J French, Paula D Freyer, Lin Shao, Frank A Garner |
On-Site Speaker (Planned) |
Janelle P. Wharry |
Abstract Scope |
The objective of this talk is to understand how high-dose irradiation affects the microstructure of a weld repair of a previously irradiated steel. Weld repairs of irradiated reactor internal components may be necessary during life extensions of light water reactors. This work will focus on specimens of AISI 304 stainless steel, pre-irradiated in EBR-II to ~3-28 displacements per atom (dpa) at ~415°C. A single-pass laser weld was made on each specimen. Weld cross-sections were re-irradiated with Fe2+ ions to an additional 50 dpa. Compared to the as-welded microstructure, additional dislocation loops nucleate throughout the ion irradiated layer. At the ion damage peak, cavities are replaced by precipitates. The role of injected interstitials and interstitial diffusion will be discussed with respect to the cavity-to-precipitate transformation mechanism, having implications on neutron pre-conditioning studies. The talk will also discuss the consequences of these results on the viability of weld repairs of reactor internals. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |