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A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al

We present a quantum-mechanical study of thermodynamic, structural, elastic, and magnetic properties of selected antiphase boundaries (APBs) in Fe [Formula: see text] Al with the D0 [Formula: see text] crystal structure with and without Cr atoms. The computed APBs are sharp (not thermal), and they h...

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Autores principales: Friák, Martin, Všianská, Monika, Šob, Mojmír
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6926628/
https://www.ncbi.nlm.nih.gov/pubmed/31795289
http://dx.doi.org/10.3390/ma12233954
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author Friák, Martin
Všianská, Monika
Šob, Mojmír
author_facet Friák, Martin
Všianská, Monika
Šob, Mojmír
author_sort Friák, Martin
collection PubMed
description We present a quantum-mechanical study of thermodynamic, structural, elastic, and magnetic properties of selected antiphase boundaries (APBs) in Fe [Formula: see text] Al with the D0 [Formula: see text] crystal structure with and without Cr atoms. The computed APBs are sharp (not thermal), and they have {001} crystallographic orientation. They are characterized by a mutual shift of grains by 1/2〈100〉a where a is the lattice parameter of a cube-shaped 16-atom elementary cell of Fe [Formula: see text] Al, i.e., they affect the next nearest neighbors (APB-NNN type, also called APB-D0 [Formula: see text]). Regarding clean APBs in Fe [Formula: see text] Al, the studied ones have only a very minor impact on the structural and magnetic properties, including local magnetic moments, and the APB energy is rather low, about 80 ± 25 mJ/m [Formula: see text]. Interestingly, they have a rather strong impact on the anisotropic (tensorial) elastic properties with the APB-induced change from a cubic symmetry to a tetragonal one, which is sensitively reflected by the directional dependence of linear compressibility. The Cr atoms have a strong impact on magnetic properties and a complex influence on the energetics of APBs. In particular, the Cr atoms in Fe [Formula: see text] Al exhibit clustering tendencies even in the presence of APBs and cause a transition from a ferromagnetic (Cr-free Fe [Formula: see text] Al) into a ferrimagnetic state. The Fe atoms with Cr atoms in their first coordination shell have their local atomic magnetic moments reduced. This reduction is synergically enhanced (to the point when Fe atoms are turned non-magnetic) when the influence of clustering of Cr atoms is combined with APBs, which offer specific atomic environments not existing in the APB-free bulk Fe [Formula: see text] Al. The impact of Cr atoms on APB energies in Fe [Formula: see text] Al is found to be ambiguous, including reduction, having a negligible influence or increasing APB energies depending on the local atomic configuration of Cr atoms, as well as their concentration.
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spelling pubmed-69266282019-12-24 A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al Friák, Martin Všianská, Monika Šob, Mojmír Materials (Basel) Article We present a quantum-mechanical study of thermodynamic, structural, elastic, and magnetic properties of selected antiphase boundaries (APBs) in Fe [Formula: see text] Al with the D0 [Formula: see text] crystal structure with and without Cr atoms. The computed APBs are sharp (not thermal), and they have {001} crystallographic orientation. They are characterized by a mutual shift of grains by 1/2〈100〉a where a is the lattice parameter of a cube-shaped 16-atom elementary cell of Fe [Formula: see text] Al, i.e., they affect the next nearest neighbors (APB-NNN type, also called APB-D0 [Formula: see text]). Regarding clean APBs in Fe [Formula: see text] Al, the studied ones have only a very minor impact on the structural and magnetic properties, including local magnetic moments, and the APB energy is rather low, about 80 ± 25 mJ/m [Formula: see text]. Interestingly, they have a rather strong impact on the anisotropic (tensorial) elastic properties with the APB-induced change from a cubic symmetry to a tetragonal one, which is sensitively reflected by the directional dependence of linear compressibility. The Cr atoms have a strong impact on magnetic properties and a complex influence on the energetics of APBs. In particular, the Cr atoms in Fe [Formula: see text] Al exhibit clustering tendencies even in the presence of APBs and cause a transition from a ferromagnetic (Cr-free Fe [Formula: see text] Al) into a ferrimagnetic state. The Fe atoms with Cr atoms in their first coordination shell have their local atomic magnetic moments reduced. This reduction is synergically enhanced (to the point when Fe atoms are turned non-magnetic) when the influence of clustering of Cr atoms is combined with APBs, which offer specific atomic environments not existing in the APB-free bulk Fe [Formula: see text] Al. The impact of Cr atoms on APB energies in Fe [Formula: see text] Al is found to be ambiguous, including reduction, having a negligible influence or increasing APB energies depending on the local atomic configuration of Cr atoms, as well as their concentration. MDPI 2019-11-28 /pmc/articles/PMC6926628/ /pubmed/31795289 http://dx.doi.org/10.3390/ma12233954 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Friák, Martin
Všianská, Monika
Šob, Mojmír
A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al
title A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al
title_full A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al
title_fullStr A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al
title_full_unstemmed A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al
title_short A Quantum–Mechanical Study of Clean and Cr–Segregated Antiphase Boundaries in Fe(3)Al
title_sort quantum–mechanical study of clean and cr–segregated antiphase boundaries in fe(3)al
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6926628/
https://www.ncbi.nlm.nih.gov/pubmed/31795289
http://dx.doi.org/10.3390/ma12233954
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