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Title: Stacking fault energies of nondilute binary alloys using special quasirandom structures

Authors:
; ; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1347047
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 95; Journal Issue: 9; Related Information: CHORUS Timestamp: 2017-03-14 22:12:14; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Kaufman, Jonas L., Pomrehn, Gregory S., Pribram-Jones, Aurora, Mahjoub, Reza, Ferry, Michael, Laws, Kevin J., and Bassman, Lori. Stacking fault energies of nondilute binary alloys using special quasirandom structures. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.95.094112.
Kaufman, Jonas L., Pomrehn, Gregory S., Pribram-Jones, Aurora, Mahjoub, Reza, Ferry, Michael, Laws, Kevin J., & Bassman, Lori. Stacking fault energies of nondilute binary alloys using special quasirandom structures. United States. doi:10.1103/PhysRevB.95.094112.
Kaufman, Jonas L., Pomrehn, Gregory S., Pribram-Jones, Aurora, Mahjoub, Reza, Ferry, Michael, Laws, Kevin J., and Bassman, Lori. Tue . "Stacking fault energies of nondilute binary alloys using special quasirandom structures". United States. doi:10.1103/PhysRevB.95.094112.
@article{osti_1347047,
title = {Stacking fault energies of nondilute binary alloys using special quasirandom structures},
author = {Kaufman, Jonas L. and Pomrehn, Gregory S. and Pribram-Jones, Aurora and Mahjoub, Reza and Ferry, Michael and Laws, Kevin J. and Bassman, Lori},
abstractNote = {},
doi = {10.1103/PhysRevB.95.094112},
journal = {Physical Review B},
number = 9,
volume = 95,
place = {United States},
year = {Tue Mar 14 00:00:00 EDT 2017},
month = {Tue Mar 14 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevB.95.094112

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  • We have developed 32-atom special quasi-random structures (SQSs) to model the substitutionally random pseudo-binary A3(B0.5C0.5) alloys in L12, D019, and D03 crystal structures, respectively. First-principles SQS calculations are performed to examine the phase stability of the recently identified L12-Co3Al0.5W0.5 compound in the Co-Al-W ternary system. By computing total energy as a function of applied strain, the single-crystal elastic constants of L12-Co3Al0.5W0.5 are also predicted and our results show excellent agreement with recent experimental measurements.
  • Structural models needed in calculations of properties of substitutionally random {ital A}{sub 1{minus}{ital x}B{ital x}} alloys are usually constructed by randomly occupying each of the {ital N} sites of a periodic cell by {ital A} or {ital B}. We show that it is possible to design special quasirandom structures'' (SQS's) that mimic for small {ital N} (even {ital N}=8) the first few, physically most relevant radial correlation functions of an infinite, perfectly random structure far better than the standard technique does. These SQS's are shown to be short-period superlattices of 4--16 atoms/cell whose layers are stacked in rather nonstandard orientationsmore » (e.g., (113), (331), and (115)). Since these SQS's mimic well the local atomic structure of the random alloy, their electronic properties, calculable via first-principles techniques, provide a representation of the electronic structure of the alloy. We demonstrate the usefulness of these SQS's by applying them to semiconductor alloys. We calculate their electronic structure, total energy, and equilibrium geometry, and compare the results to experimental data.« less
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  • Twenty-one {l_angle}110{r_angle} symmetric tilt grain boundaries (GB{close_quote}s) are investigated with atomistic simulations, using an embedded-atom method (EAM) potential for a low stacking-fault energy fcc metal. Lattice statics simulations with a large number of initial configurations are used to identify both the equilibrium and metastable structures at 0 K. The level of difficulty in finding the equilibrium structures is quantitatively assessed. The stability of the structures at an elevated temperature is investigated by Monte Carlo annealing. A form of GB dissociation is identified in a number of the boundaries. These structures are used to develop a dislocation model of GB dissociationmore » by stacking-fault emission. Also, an attempt is made to apply the structural unit model (SUM) to the simulated boundaries and problems that are encountered for GB structures in low stacking-fault energy metals are enumerated and discussed. {copyright} {ital 1996 The American Physical Society.}« less