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Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade
Large defects are the main factor leading to the degradation of material properties under irradiation environments. It is commonly assumed that the large defects are mainly formed through cluster growth under continuous irradiations. Besides this mechanism, recent experiments and simulations show th...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group
2016
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4751535/ https://www.ncbi.nlm.nih.gov/pubmed/26868496 http://dx.doi.org/10.1038/srep21034 |
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author | Zhou, Wei Tian, Jiting Zheng, Jian Xue, Jianming Peng, Shuming |
author_facet | Zhou, Wei Tian, Jiting Zheng, Jian Xue, Jianming Peng, Shuming |
author_sort | Zhou, Wei |
collection | PubMed |
description | Large defects are the main factor leading to the degradation of material properties under irradiation environments. It is commonly assumed that the large defects are mainly formed through cluster growth under continuous irradiations. Besides this mechanism, recent experiments and simulations show that sometimes an individual ion can also directly create a large defect. Here we report a novel mechanism for the formation of the large defects, as discovered by our Molecular Dynamics (MD) simulations of the collision cascades in hcp Zirconium (Zr): a pre-existing edge dislocation (ED) can significantly promote the nucleation of the vacancy clusters, and even facilitate the direct formation of an experimental-scale large vacancy loop (about 3 nm) in only one single displacement cascade. This dislocation-related mechanism may be the key for understanding the experimental results in the low-dose irradiated Zr where the high-density large dislocation loops are observed but difficult to be explained by the two mechanisms mentioned above. Considering that intrinsic dislocations exist in nearly all crystalline materials, our results provide a significant concept: pre-existing dislocations have a strong influence on the primary damage production, and taking them into account is indispensable for assessing and improving the material’s irradiation-resistance. |
format | Online Article Text |
id | pubmed-4751535 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2016 |
publisher | Nature Publishing Group |
record_format | MEDLINE/PubMed |
spelling | pubmed-47515352016-02-22 Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade Zhou, Wei Tian, Jiting Zheng, Jian Xue, Jianming Peng, Shuming Sci Rep Article Large defects are the main factor leading to the degradation of material properties under irradiation environments. It is commonly assumed that the large defects are mainly formed through cluster growth under continuous irradiations. Besides this mechanism, recent experiments and simulations show that sometimes an individual ion can also directly create a large defect. Here we report a novel mechanism for the formation of the large defects, as discovered by our Molecular Dynamics (MD) simulations of the collision cascades in hcp Zirconium (Zr): a pre-existing edge dislocation (ED) can significantly promote the nucleation of the vacancy clusters, and even facilitate the direct formation of an experimental-scale large vacancy loop (about 3 nm) in only one single displacement cascade. This dislocation-related mechanism may be the key for understanding the experimental results in the low-dose irradiated Zr where the high-density large dislocation loops are observed but difficult to be explained by the two mechanisms mentioned above. Considering that intrinsic dislocations exist in nearly all crystalline materials, our results provide a significant concept: pre-existing dislocations have a strong influence on the primary damage production, and taking them into account is indispensable for assessing and improving the material’s irradiation-resistance. Nature Publishing Group 2016-02-12 /pmc/articles/PMC4751535/ /pubmed/26868496 http://dx.doi.org/10.1038/srep21034 Text en Copyright © 2016, Macmillan Publishers Limited http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ |
spellingShingle | Article Zhou, Wei Tian, Jiting Zheng, Jian Xue, Jianming Peng, Shuming Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade |
title | Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade |
title_full | Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade |
title_fullStr | Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade |
title_full_unstemmed | Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade |
title_short | Dislocation-enhanced experimental-scale vacancy loop formation in hcp Zirconium in one single collision cascade |
title_sort | dislocation-enhanced experimental-scale vacancy loop formation in hcp zirconium in one single collision cascade |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4751535/ https://www.ncbi.nlm.nih.gov/pubmed/26868496 http://dx.doi.org/10.1038/srep21034 |
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