Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures
In this paper, atomistic studies show that Cantor alloys containing a pre-existing crack under tension are ductile at cryogenic temperatures. Specifically, the effects of crack length on the mechanical properties of single-crystalline Cantor alloys under mode I loading at the temperature of 0.1 K ar...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2022
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/159463 |
| _version_ | 1826122254803533824 |
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| author | Ji, Weiming Wu, Mao See |
| author2 | School of Mechanical and Aerospace Engineering |
| author_facet | School of Mechanical and Aerospace Engineering Ji, Weiming Wu, Mao See |
| author_sort | Ji, Weiming |
| collection | NTU |
| description | In this paper, atomistic studies show that Cantor alloys containing a pre-existing crack under tension are ductile at cryogenic temperatures. Specifically, the effects of crack length on the mechanical properties of single-crystalline Cantor alloys under mode I loading at the temperature of 0.1 K are investigated via molecular dynamics (MD) simulations. For different initial crack lengths ranging from 25 to 45 nm, the J-integral is calculated at the critical point of dislocation emission, and the work-of-fracture is calculated at the fracture strain. The results show that the Young's modulus and yield stress decrease with the increased crack length. The J-integral is not significantly affected by the crack length, due to the fact it is governed by the length-independent unstable stacking fault energy. However, the work-of-fracture increases with increased crack length. Nucleation and growth of nanosized cavities in front of the crack tip are observed and the crack propagates through coalescence of cavities, which agrees well with previous experimental findings. As the tensile strain increases, there is a transition from cavitation to shear faulting, after which the stress-strain responses are independent of the crack length. The cavitation and shear faulting dissipate a large amount of energy needed for crack propagation, leading to ductile fracture of Cantor alloys at cryogenic temperatures. |
| first_indexed | 2024-10-01T05:45:29Z |
| format | Journal Article |
| id | ntu-10356/159463 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T05:45:29Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | ntu-10356/1594632023-08-15T08:04:58Z Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures Ji, Weiming Wu, Mao See School of Mechanical and Aerospace Engineering Engineering::Mechanical engineering Cantor Alloys Molecular Dynamics In this paper, atomistic studies show that Cantor alloys containing a pre-existing crack under tension are ductile at cryogenic temperatures. Specifically, the effects of crack length on the mechanical properties of single-crystalline Cantor alloys under mode I loading at the temperature of 0.1 K are investigated via molecular dynamics (MD) simulations. For different initial crack lengths ranging from 25 to 45 nm, the J-integral is calculated at the critical point of dislocation emission, and the work-of-fracture is calculated at the fracture strain. The results show that the Young's modulus and yield stress decrease with the increased crack length. The J-integral is not significantly affected by the crack length, due to the fact it is governed by the length-independent unstable stacking fault energy. However, the work-of-fracture increases with increased crack length. Nucleation and growth of nanosized cavities in front of the crack tip are observed and the crack propagates through coalescence of cavities, which agrees well with previous experimental findings. As the tensile strain increases, there is a transition from cavitation to shear faulting, after which the stress-strain responses are independent of the crack length. The cavitation and shear faulting dissipate a large amount of energy needed for crack propagation, leading to ductile fracture of Cantor alloys at cryogenic temperatures. Ministry of Education (MOE) This research is supported by the Ministry of Education, Singapore, under its Academic Research Fund Tier 1, Project Number RG155/19 (S). The computational work for this article was performed using resources of the Singapore National Supercomputing Centre under Project ID 12002312. 2022-06-24T02:36:34Z 2022-06-24T02:36:34Z 2021 Journal Article Ji, W. & Wu, M. S. (2021). Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures. Engineering Fracture Mechanics, 258, 108120-. https://dx.doi.org/10.1016/j.engfracmech.2021.108120 0013-7944 https://hdl.handle.net/10356/159463 10.1016/j.engfracmech.2021.108120 2-s2.0-85119412885 258 108120 en RG155/19 (S) 12002312 Engineering Fracture Mechanics 10.21979/N9/DG1D4H © 2021 Elsevier Ltd. All rights reserved. |
| spellingShingle | Engineering::Mechanical engineering Cantor Alloys Molecular Dynamics Ji, Weiming Wu, Mao See Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures |
| title | Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures |
| title_full | Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures |
| title_fullStr | Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures |
| title_full_unstemmed | Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures |
| title_short | Atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures |
| title_sort | atomistic studies of ductile fracture of a single crystalline cantor alloy containing a crack at cryogenic temperatures |
| topic | Engineering::Mechanical engineering Cantor Alloys Molecular Dynamics |
| url | https://hdl.handle.net/10356/159463 |
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