About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
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Computational Materials Science and Engineering of Materials in Nuclear Reactors
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Presentation Title |
A First-principles Investigation on the Co-segregation Energetics of Chromium-helium at Grain Boundaries in α-Fe |
Author(s) |
Sainyam Nagar, Pulkit Garg, Nitin C Muthegowda, Mehul A Bhatia, Ilaksh Adlakha, Kiran N Solanki |
On-Site Speaker (Planned) |
Sainyam Nagar |
Abstract Scope |
Mitigating the radiation damage of structural materials during nuclear applications is critical to extend the lifetime of nuclear reactors. The mechanical properties of structural alloys such-as ferritic/martensitic steels are affected by the presence of impurities (hydrogen/helium). Thus, the co-segregation energetics of Cr-He at Σ3(111), Σ9(114) and Σ11(113) GBs in α-Fe were investigated using first-principles calculations. In the absence of Cr, maximum of four He atoms segregated favorably at interstitial tetrahedral sites at α-Fe GBs; however, presence of Cr reduced segregation tendency of He atoms at GBs. The suppressing effect of Cr on He segregation was further examined using density of states and charge transfer calculations. Furthermore, presence of Cr atom increased the energy barrier for He migration thereby reducing the mobility of He atoms along the GBs. Thus, Cr addition suppresses He segregation at α-Fe GBs and reduces the deteriorating effects of He on ferritic steels for nuclear reactor applications. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |