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Title: Atomistic mechanisms of morphological evolution and segregation in U-Zr alloys

Authors:
ORCiD logo; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1323571
Grant/Contract Number:
00123590
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Acta Materialia
Additional Journal Information:
Journal Volume: 115; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-06 15:55:18; Journal ID: ISSN 1359-6454
Publisher:
Elsevier
Country of Publication:
United States
Language:
English

Citation Formats

Moore, A. P., Deo, C., Baskes, M. I., and Okuniewski, M. A. Atomistic mechanisms of morphological evolution and segregation in U-Zr alloys. United States: N. p., 2016. Web. doi:10.1016/j.actamat.2016.05.052.
Moore, A. P., Deo, C., Baskes, M. I., & Okuniewski, M. A. Atomistic mechanisms of morphological evolution and segregation in U-Zr alloys. United States. doi:10.1016/j.actamat.2016.05.052.
Moore, A. P., Deo, C., Baskes, M. I., and Okuniewski, M. A. 2016. "Atomistic mechanisms of morphological evolution and segregation in U-Zr alloys". United States. doi:10.1016/j.actamat.2016.05.052.
@article{osti_1323571,
title = {Atomistic mechanisms of morphological evolution and segregation in U-Zr alloys},
author = {Moore, A. P. and Deo, C. and Baskes, M. I. and Okuniewski, M. A.},
abstractNote = {},
doi = {10.1016/j.actamat.2016.05.052},
journal = {Acta Materialia},
number = C,
volume = 115,
place = {United States},
year = 2016,
month = 8
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.actamat.2016.05.052

Citation Metrics:
Cited by: 1work
Citation information provided by
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  • Segregation to {gamma}/{gamma} interfaces in non-stoichiometric L1{sub 0} TiAl is analyzed on the atomic level using a Monte Carlo method and central force many-body potentials of the Finnis-Sinclair type to describe atomic interactions. While these alloys are Ti-rich and thus segregation of Ti is of principal interest, the calculations have also been made for Al-rich bulk in order to investigate the generality of structural features revealed in this study. No segregation takes place to ordered twins but both Ti and Al, depending on which of them is in surplus in the bulk, segregate to the 120{degree} rotational faults, pseudotwins andmore » ordered twins with the APB. The segregation of Ti to 120{degree} rotational faults and pseudotwins leads to an apparent formation of a thin layer of the DO{sub 19} Ti{sub 3}Al at these interfaces. However, an analogous DO{sub 19} type structure, but with stoichiometry Al{sub 3}Ti, is also obtained when Al segregates to these interfaces. Hence, the segregation propensity cannot be associated with a thermodynamically favored formation of the DO{sub 19} phase at {gamma}/{gamma} interfaces. Rather, the distribution of Al sites that are favored for segregation is such that their filling by Ti leads to the formation of the structure which is the same as that of the basal plane in Ti{sub 3}Al. Consequently, the conspicuous formation of the DO{sub 19} Ti{sub 3}Al at 120{degree} rotational faults and pseudotwins results from the topology of the nearest neighbors of the atoms at these interfaces. Segregation is also favored to the ordered twin with the APB but it invokes dissociation of this interfaces. Segregation is also favored to the ordered twin with the APB but it invokes dissociation of this interface into the 120{degree} rotational fault and the pseudotwin which then possess the same structure as the corresponding isolated interfaces.« less
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  • Single-phase concentrated solid solution alloys have attracted wide interest due to their superior mechanical properties and enhanced radiation tolerance, which make them promising candidates for the structural applications in next-generation nuclear reactors. However, little has been understood about the intrinsic stability of their as-synthesized, high-entropy configurations against radiation damage. In this paper, we report the element segregation in CrFeCoNi, CrFeCoNiMn, and CrFeCoNiPd equiatomic alloys when subjected to 1250 kV electron irradiations at 400 °C up to a damage level of 1 displacement per atom. Cr/Fe/Mn/Pd can deplete and Co/Ni can accumulate at radiation-induced dislocation loops, while the actively segregating elementsmore » are alloy-specific. Moreover, electron-irradiated matrix of CrFeCoNiMn and CrFeCoNiPd shows L1 0 (NiMn)-type ordering decomposition and <001>-oriented spinodal decomposition between Co/Ni and Pd, respectively. Finally, these findings are rationalized based on the atomic size difference and enthalpy of mixing between the alloying elements, and identify a new important requirement to the design of radiation-tolerant alloys through modification of the composition.« less