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Title: Defect-induced change of temperature-dependent elastic constants in BCC iron

Abstract

The effects of radiation-induced defects (randomly distributed vacancies, voids, and interstitial dislocation loops) on temperature-dependent elastic constants, C11, C12, and C44 in BCC iron, are studied with molecular dynamics method. The elastic constants are found to decrease with increasing temperatures for all cases containing different defects. The presence of vacancies, voids, or interstitial loops further decreases the elastic constants. For a given number of point defects, the randomly distributed vacancies show the strongest effect compared to voids or interstitial loops. All these results are expected to provide useful information to combine with experimental results for further understanding of radiation damage.

Authors:
; ORCiD logo; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1355083
Report Number(s):
PNNL-SA-122758
Journal ID: ISSN 0022-3115; AT2030110
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Nuclear Materials; Journal Volume: 490; Journal Issue: C
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; elastic constants; vacancy; void; dislocation loop; molecular dynamics; defect

Citation Formats

Gao, N., Setyawan, W., Zhang, S. H., and Wang, Z. G. Defect-induced change of temperature-dependent elastic constants in BCC iron. United States: N. p., 2017. Web. doi:10.1016/j.jnucmat.2017.04.005.
Gao, N., Setyawan, W., Zhang, S. H., & Wang, Z. G. Defect-induced change of temperature-dependent elastic constants in BCC iron. United States. doi:10.1016/j.jnucmat.2017.04.005.
Gao, N., Setyawan, W., Zhang, S. H., and Wang, Z. G. Sat . "Defect-induced change of temperature-dependent elastic constants in BCC iron". United States. doi:10.1016/j.jnucmat.2017.04.005.
@article{osti_1355083,
title = {Defect-induced change of temperature-dependent elastic constants in BCC iron},
author = {Gao, N. and Setyawan, W. and Zhang, S. H. and Wang, Z. G.},
abstractNote = {The effects of radiation-induced defects (randomly distributed vacancies, voids, and interstitial dislocation loops) on temperature-dependent elastic constants, C11, C12, and C44 in BCC iron, are studied with molecular dynamics method. The elastic constants are found to decrease with increasing temperatures for all cases containing different defects. The presence of vacancies, voids, or interstitial loops further decreases the elastic constants. For a given number of point defects, the randomly distributed vacancies show the strongest effect compared to voids or interstitial loops. All these results are expected to provide useful information to combine with experimental results for further understanding of radiation damage.},
doi = {10.1016/j.jnucmat.2017.04.005},
journal = {Journal of Nuclear Materials},
number = C,
volume = 490,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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