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Title: Pressure effect on stabilities of self-Interstitials in HCP structures

Abstract

The self-interstitial atoms (SIAs) mediate the evolution of micro-structures which is crucial in understanding the instabilities of hexagonal close packed (HCP) structures. Taken zirconium as a prototype, we investigate the pressure effect on the stabilities of SIAs using first-principles calculations based on density-functional theory. We found that the pressure greatly affects the stability of the SIAs. The SIAs in basal planes are more stable to changes in pressure. The most stable SIA configuration changes from basal octahedral (BO) to octahedral (O) at pressure of 21 GPa. The lowest formation enthalpy configuration switches from BO to S (split-dumbbell) at P = 30 GPa. Our results reveal that it is important to take the pressure effect into account when predicting the micro-structural evolution of HCP structures.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1171297
Report Number(s):
PNNL-SA-105073
600305000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Scientific Reports, 4:Article No. 5735
Country of Publication:
United States
Language:
English
Subject:
INTERSTITIALS; ZIRCONIUM; PRESSURE DEPENDENCE; Interstitials; Zirconium; Pressure effect; Ab initio calculation

Citation Formats

Peng, Qing, Ji, Wei, Lian, Jie, Chen, Xiao-jia, Huang, Hanchen, Gao, Fei, and De, Suvranu. Pressure effect on stabilities of self-Interstitials in HCP structures. United States: N. p., 2014. Web. doi:10.1038/srep05735.
Peng, Qing, Ji, Wei, Lian, Jie, Chen, Xiao-jia, Huang, Hanchen, Gao, Fei, & De, Suvranu. Pressure effect on stabilities of self-Interstitials in HCP structures. United States. doi:10.1038/srep05735.
Peng, Qing, Ji, Wei, Lian, Jie, Chen, Xiao-jia, Huang, Hanchen, Gao, Fei, and De, Suvranu. Fri . "Pressure effect on stabilities of self-Interstitials in HCP structures". United States. doi:10.1038/srep05735.
@article{osti_1171297,
title = {Pressure effect on stabilities of self-Interstitials in HCP structures},
author = {Peng, Qing and Ji, Wei and Lian, Jie and Chen, Xiao-jia and Huang, Hanchen and Gao, Fei and De, Suvranu},
abstractNote = {The self-interstitial atoms (SIAs) mediate the evolution of micro-structures which is crucial in understanding the instabilities of hexagonal close packed (HCP) structures. Taken zirconium as a prototype, we investigate the pressure effect on the stabilities of SIAs using first-principles calculations based on density-functional theory. We found that the pressure greatly affects the stability of the SIAs. The SIAs in basal planes are more stable to changes in pressure. The most stable SIA configuration changes from basal octahedral (BO) to octahedral (O) at pressure of 21 GPa. The lowest formation enthalpy configuration switches from BO to S (split-dumbbell) at P = 30 GPa. Our results reveal that it is important to take the pressure effect into account when predicting the micro-structural evolution of HCP structures.},
doi = {10.1038/srep05735},
journal = {Scientific Reports, 4:Article No. 5735},
number = ,
volume = ,
place = {United States},
year = {Fri Jul 18 00:00:00 EDT 2014},
month = {Fri Jul 18 00:00:00 EDT 2014}
}
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