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Title: Atomistic modeling of Mg/Nb interfaces: shear strength and interaction with lattice glide dislocations

Abstract

Here, using a newly developed embedded-atom-method potential for Mg–Nb, the semi-coherent Mg/Nb interface with the Kurdjumov–Sachs orientation relationship is studied. Atomistic simulations have been carried out to understand the shear strength of the interface, as well as the interaction between lattice glide dislocations and the interface. The interface shear mechanisms are dependent on the shear loading directions, through either interface sliding between Mg and Nb atomic layers or nucleation and gliding of Shockley partial dislocations in between the first two atomic planes in Mg at the interface. The shear strength for the Mg/Nb interface is found to be generally high, in the range of 0.9–1.3 GPa depending on the shear direction. As a consequence, the extents of dislocation core spread into the interface are considerably small, especially when compared to the case of other “weak” interfaces such as the Cu/Nb interface.

Authors:
ORCiD logo [1];  [2]; ORCiD logo [3];  [4]; ORCiD logo [3]
  1. Indian Institute of Technology (IIT), Chennai (India); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Louisiana State Univ., Baton Rouge, LA (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. Univ. of Nebraska-Lincoln, Lincoln, NE (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1408833
Report Number(s):
LA-UR-16-28211
Journal ID: ISSN 0022-2461; TRN: US1703179
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Materials Science
Additional Journal Information:
Journal Name: Journal of Materials Science; Journal ID: ISSN 0022-2461
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Yadav, Satyesh Kumar, Shao, S., Chen, Youxing, Wang, J., and Liu, Xiang -Yang. Atomistic modeling of Mg/Nb interfaces: shear strength and interaction with lattice glide dislocations. United States: N. p., 2017. Web. doi:10.1007/s10853-017-1703-4.
Yadav, Satyesh Kumar, Shao, S., Chen, Youxing, Wang, J., & Liu, Xiang -Yang. Atomistic modeling of Mg/Nb interfaces: shear strength and interaction with lattice glide dislocations. United States. doi:10.1007/s10853-017-1703-4.
Yadav, Satyesh Kumar, Shao, S., Chen, Youxing, Wang, J., and Liu, Xiang -Yang. 2017. "Atomistic modeling of Mg/Nb interfaces: shear strength and interaction with lattice glide dislocations". United States. doi:10.1007/s10853-017-1703-4.
@article{osti_1408833,
title = {Atomistic modeling of Mg/Nb interfaces: shear strength and interaction with lattice glide dislocations},
author = {Yadav, Satyesh Kumar and Shao, S. and Chen, Youxing and Wang, J. and Liu, Xiang -Yang},
abstractNote = {Here, using a newly developed embedded-atom-method potential for Mg–Nb, the semi-coherent Mg/Nb interface with the Kurdjumov–Sachs orientation relationship is studied. Atomistic simulations have been carried out to understand the shear strength of the interface, as well as the interaction between lattice glide dislocations and the interface. The interface shear mechanisms are dependent on the shear loading directions, through either interface sliding between Mg and Nb atomic layers or nucleation and gliding of Shockley partial dislocations in between the first two atomic planes in Mg at the interface. The shear strength for the Mg/Nb interface is found to be generally high, in the range of 0.9–1.3 GPa depending on the shear direction. As a consequence, the extents of dislocation core spread into the interface are considerably small, especially when compared to the case of other “weak” interfaces such as the Cu/Nb interface.},
doi = {10.1007/s10853-017-1703-4},
journal = {Journal of Materials Science},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

Journal Article:
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  • No abstract prepared.