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Electronic Mechanism of Martensitic Transformation in Nb-doped NiTi Alloys: A First-Principles Investigation
[Image: see text] The effect of Nb on the crystal structures and electronic mechanism of martensitic transformation in Ni(50)Ti(50–x)Nb(x) alloys is investigated by first principles. The lattice parameters, the formation energy, the middle eigenvalue of the transformation stretch tensor (λ(2)), and...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Chemical Society
2021
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8412941/ https://www.ncbi.nlm.nih.gov/pubmed/34497897 http://dx.doi.org/10.1021/acsomega.1c02601 |
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author | Yang, Xiaolan Shang, Jiaxiang |
author_facet | Yang, Xiaolan Shang, Jiaxiang |
author_sort | Yang, Xiaolan |
collection | PubMed |
description | [Image: see text] The effect of Nb on the crystal structures and electronic mechanism of martensitic transformation in Ni(50)Ti(50–x)Nb(x) alloys is investigated by first principles. The lattice parameters, the formation energy, the middle eigenvalue of the transformation stretch tensor (λ(2)), and the energy difference between the parent and martensite (ΔE) as a function of Nb content x (x = 0, 2.08, 6.25, 8.33, 10.42, 12.5, 18.75) are calculated. Lattice parameters increase with the increase of Nb content. The formation energies of the parent B2 phase, martensite orthorhombic B19, and monoclinic B19′ increase with the increase of Nb content. It is also found that at ≤10.42 at. % Nb, the martensite stable phase is monoclinic structure B19′; at >10.42 at. % Nb, the orthorhombic crystal structure B19 is formed. The energy difference between the parent and martensite means that the transformation temperature decreases with increasing Nb concentration at Nb ≤ 10.42 at. % and increases at >10.42 at. % Nb. The λ(2) of the NiTiNb alloys have the same value of about 0.95 with low Nb content. Furthermore, the electronic structure mechanisms behind the martensitic transformations are discussed in detail based on the density of states. |
format | Online Article Text |
id | pubmed-8412941 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2021 |
publisher | American Chemical Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-84129412021-09-07 Electronic Mechanism of Martensitic Transformation in Nb-doped NiTi Alloys: A First-Principles Investigation Yang, Xiaolan Shang, Jiaxiang ACS Omega [Image: see text] The effect of Nb on the crystal structures and electronic mechanism of martensitic transformation in Ni(50)Ti(50–x)Nb(x) alloys is investigated by first principles. The lattice parameters, the formation energy, the middle eigenvalue of the transformation stretch tensor (λ(2)), and the energy difference between the parent and martensite (ΔE) as a function of Nb content x (x = 0, 2.08, 6.25, 8.33, 10.42, 12.5, 18.75) are calculated. Lattice parameters increase with the increase of Nb content. The formation energies of the parent B2 phase, martensite orthorhombic B19, and monoclinic B19′ increase with the increase of Nb content. It is also found that at ≤10.42 at. % Nb, the martensite stable phase is monoclinic structure B19′; at >10.42 at. % Nb, the orthorhombic crystal structure B19 is formed. The energy difference between the parent and martensite means that the transformation temperature decreases with increasing Nb concentration at Nb ≤ 10.42 at. % and increases at >10.42 at. % Nb. The λ(2) of the NiTiNb alloys have the same value of about 0.95 with low Nb content. Furthermore, the electronic structure mechanisms behind the martensitic transformations are discussed in detail based on the density of states. American Chemical Society 2021-08-19 /pmc/articles/PMC8412941/ /pubmed/34497897 http://dx.doi.org/10.1021/acsomega.1c02601 Text en © 2021 The Authors. Published by American Chemical Society https://creativecommons.org/licenses/by-nc-nd/4.0/Permits non-commercial access and re-use, provided that author attribution and integrity are maintained; but does not permit creation of adaptations or other derivative works (https://creativecommons.org/licenses/by-nc-nd/4.0/). |
spellingShingle | Yang, Xiaolan Shang, Jiaxiang Electronic Mechanism of Martensitic Transformation in Nb-doped NiTi Alloys: A First-Principles Investigation |
title | Electronic Mechanism of Martensitic Transformation
in Nb-doped NiTi Alloys: A First-Principles Investigation |
title_full | Electronic Mechanism of Martensitic Transformation
in Nb-doped NiTi Alloys: A First-Principles Investigation |
title_fullStr | Electronic Mechanism of Martensitic Transformation
in Nb-doped NiTi Alloys: A First-Principles Investigation |
title_full_unstemmed | Electronic Mechanism of Martensitic Transformation
in Nb-doped NiTi Alloys: A First-Principles Investigation |
title_short | Electronic Mechanism of Martensitic Transformation
in Nb-doped NiTi Alloys: A First-Principles Investigation |
title_sort | electronic mechanism of martensitic transformation
in nb-doped niti alloys: a first-principles investigation |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8412941/ https://www.ncbi.nlm.nih.gov/pubmed/34497897 http://dx.doi.org/10.1021/acsomega.1c02601 |
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