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Title: Monte Carlo modeling of recrystallization processes in α-uranium

Abstract

In this study, starting with electron backscattered diffraction (EBSD) data obtained from a warm clock-rolled α-uranium deformation microstructure, a Potts Monte Carlo model was used to simulate static site-saturated recrystallization while testing a number of different conditions for the assignment of recrystallized nuclei within the microstructure. The simulations support observations that recrystallized nuclei within α-uranium form preferentially on non-twin high-angle grain boundary sites at 450 °C, and demonstrate that the most likely nucleation sites on these boundaries can be identified by the surrounding degree of Kernel Average Misorientation (KAM), which may be considered as a proxy for the local geometrically necessary dislocation (GND) density.

Authors:
; ; ;
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Oak Ridge Y-12 Plant (Y-12), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1356133
Report Number(s):
LA-UR-16-25109; MS/GAR-170323-2
Journal ID: ISSN 0022-3115
Grant/Contract Number:
AC52-06NA25396; NA0001942; DE NA 0001942; 20140630 ER
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 492; Journal Issue: C; Journal ID: ISSN 0022-3115
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; uranium recrystallization Potts modeling EBSD Monte Carlo; α-uranium; recrystallization; Monte Carlo; Potts modeling; EBSD

Citation Formats

Steiner, M. A., McCabe, R. J., Garlea, E., and Agnew, S. R.. Monte Carlo modeling of recrystallization processes in α-uranium. United States: N. p., 2017. Web. doi:10.1016/j.jnucmat.2017.04.026.
Steiner, M. A., McCabe, R. J., Garlea, E., & Agnew, S. R.. Monte Carlo modeling of recrystallization processes in α-uranium. United States. doi:10.1016/j.jnucmat.2017.04.026.
Steiner, M. A., McCabe, R. J., Garlea, E., and Agnew, S. R.. 2017. "Monte Carlo modeling of recrystallization processes in α-uranium". United States. doi:10.1016/j.jnucmat.2017.04.026.
@article{osti_1356133,
title = {Monte Carlo modeling of recrystallization processes in α-uranium},
author = {Steiner, M. A. and McCabe, R. J. and Garlea, E. and Agnew, S. R.},
abstractNote = {In this study, starting with electron backscattered diffraction (EBSD) data obtained from a warm clock-rolled α-uranium deformation microstructure, a Potts Monte Carlo model was used to simulate static site-saturated recrystallization while testing a number of different conditions for the assignment of recrystallized nuclei within the microstructure. The simulations support observations that recrystallized nuclei within α-uranium form preferentially on non-twin high-angle grain boundary sites at 450 °C, and demonstrate that the most likely nucleation sites on these boundaries can be identified by the surrounding degree of Kernel Average Misorientation (KAM), which may be considered as a proxy for the local geometrically necessary dislocation (GND) density.},
doi = {10.1016/j.jnucmat.2017.04.026},
journal = {Journal of Nuclear Materials},
number = C,
volume = 492,
place = {United States},
year = 2017,
month = 8
}

Journal Article:
Free Publicly Available Full Text
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