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He J, Li Z, Xu X, Tan Q, Weng X, Liu L, Qu J, Liao C, Wang Y. High-temperature strain sensor based on sapphire fiber Bragg grating. OPTICS LETTERS 2024; 49:446-449. [PMID: 38300027 DOI: 10.1364/ol.509397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 12/12/2023] [Indexed: 02/02/2024]
Abstract
Sapphire fiber Bragg grating (SFBG) is a promising high-temperature strain sensor due to its melting point of 2045°C. However, the study on the long-term stability of SFBG under high temperature with an applied strain is still missing. In this paper, we reported for the first time to our knowledge on the critical temperature point of plastic deformation of the SFBG and demonstrated that the SFBG strain sensor can operate stably below 1200°C. At first, we experimentally investigated the topography and the spectral characteristics of the SFBG at different temperatures (i.e., 25°C, 1180°C, and 1600°C) with applied 650 µε. The reflection peak of the SFBG exhibits a redshift of about 15 nm and broadens gradually within 8 h at 1600°C, and the tensile force value decreases by 0.60 N in this process. After the test, the diameter of the SFBG region decreases from 100 to 88.6 µm, and the grating period is extended from 1.76 to 1.79 µm. This indicates that the plastic deformation of the SFBG happened indeed, and it was elongated irreversibly. Moreover, the stability of the Bragg wavelength of the SFBG under high temperature with the applied strain was evaluated. The result demonstrates the SFBG can be used to measure strain reliably below 1200°C. Furthermore, the strain experiments of SFBG at 25°C, 800°C, and 1100°C have been carried out. A linear fitting curve with high fitness (R2 > 0.99) and a lower strain measurement error (<15 µε) can be obtained. The aforementioned results make SFBG promising for high-temperature strain sensing in many fields, such as, power plants, gas turbines, and aerospace vehicles.
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Ispánovity PD, Ugi D, Péterffy G, Knapek M, Kalácska S, Tüzes D, Dankházi Z, Máthis K, Chmelík F, Groma I. Dislocation avalanches are like earthquakes on the micron scale. Nat Commun 2022; 13:1975. [PMID: 35418187 PMCID: PMC9007997 DOI: 10.1038/s41467-022-29044-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 02/16/2022] [Indexed: 11/29/2022] Open
Abstract
Compression experiments on micron-scale specimens and acoustic emission (AE) measurements on bulk samples revealed that the dislocation motion resembles a stick-slip process - a series of unpredictable local strain bursts with a scale-free size distribution. Here we present a unique experimental set-up, which detects weak AE waves of dislocation slip during the compression of Zn micropillars. Profound correlation is observed between the energies of deformation events and the emitted AE signals that, as we conclude, are induced by the collective dissipative motion of dislocations. The AE data also reveal a two-level structure of plastic events, which otherwise appear as a single stress drop. Hence, our experiments and simulations unravel the missing relationship between the properties of acoustic signals and the corresponding local deformation events. We further show by statistical analyses that despite fundamental differences in deformation mechanism and involved length- and time-scales, dislocation avalanches and earthquakes are essentially alike.
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Grants
- TKP2020-IKA-05 Emberi Eroforrások Minisztériuma (Ministry of Human Capacities)
- NKFIH-K-119561 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- NKFIH-FK-138975 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- NKFIH-K-119561 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- NKFIH-FK-138975 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- NKFIH-K-119561 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- NKFIH-K-119561 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- NKFIH-FK-138975 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- NKFIH-K-119561 Nemzeti Kutatási, Fejlesztési és Innovációs Hivatal (NKFI Office)
- 19-22604S Grantová Agentura České Republiky (Grant Agency of the Czech Republic)
- Innovációs és Technológiai Minisztérium: ÚNKP-20-3, ÚNKP-21-4, ÚNKP-21-3
- Innovációs és Technológiai Minisztérium: ÚNKP-21-3
- Czech Science Foundation (grant No.19-22604S)
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Affiliation(s)
- Péter Dusán Ispánovity
- Eötvös Loránd University, Department of Materials Physics, Pázmány Péter sétany 1/a., 1117 Budapest, Hungary.
| | - Dávid Ugi
- Eötvös Loránd University, Department of Materials Physics, Pázmány Péter sétany 1/a., 1117 Budapest, Hungary.
| | - Gábor Péterffy
- Eötvös Loránd University, Department of Materials Physics, Pázmány Péter sétany 1/a., 1117 Budapest, Hungary
| | - Michal Knapek
- Charles University, Faculty of Mathematics and Physics, Department of Physics of Materials, Ke Karlovu 5, 121 16 Prague 2, Czech Republic
| | - Szilvia Kalácska
- Eötvös Loránd University, Department of Materials Physics, Pázmány Péter sétany 1/a., 1117 Budapest, Hungary
- Mines Saint-Etienne, Univ Lyon, CNRS, UMR 5307 LGF, Centre SMS, 158 cours Fauriel 42023, Saint-Étienne, France
| | - Dániel Tüzes
- Eötvös Loránd University, Department of Materials Physics, Pázmány Péter sétany 1/a., 1117 Budapest, Hungary
| | - Zoltán Dankházi
- Eötvös Loránd University, Department of Materials Physics, Pázmány Péter sétany 1/a., 1117 Budapest, Hungary
| | - Kristián Máthis
- Charles University, Faculty of Mathematics and Physics, Department of Physics of Materials, Ke Karlovu 5, 121 16 Prague 2, Czech Republic
| | - František Chmelík
- Charles University, Faculty of Mathematics and Physics, Department of Physics of Materials, Ke Karlovu 5, 121 16 Prague 2, Czech Republic
| | - István Groma
- Eötvös Loránd University, Department of Materials Physics, Pázmány Péter sétany 1/a., 1117 Budapest, Hungary
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Liu LZ, Zhang YY, Xie H, Jin HJ. Transition from Homogeneous to Localized Deformation in Nanoporous Gold. PHYSICAL REVIEW LETTERS 2021; 127:095501. [PMID: 34506204 DOI: 10.1103/physrevlett.127.095501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
We report a transition from homogeneous deformation to localized densification for nanoporous gold (NPG) under compression, with its solid fraction (φ) increasing to above ∼1/3. Results obtained herein suggest that this transition is inverted compared to that of conventional porous materials. Consequently, under compression, the low-density NPGs with φ<1/3 showed evident strain hardening, whereas a stress plateau was observed for high-density NPGs with φ>1/3, which is contrary to the established notions for conventional porous materials. The ligament pinch-offs and bending-dominated structures are responsible for the homogeneous deformation of low-density NPGs. For high-density NPGs, the compression- or tension-dominated structure enables the collective strain bursts in nanoligaments, resulting in localized densification and stress plateau in their compression curves. In addition to the nanosize effect, the surface-diffusion-mediated topology evolution and the large-scale crystal-lattice coherency arising from the large grain size are also decisive to the mechanical response of dealloyed NPGs, which might be universal for self-organized nanonetwork materials.
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Affiliation(s)
- Ling-Zhi Liu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, China
| | - Ye-Yuan Zhang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, China
- School of Materials Science and Engineering, University of Science and Technology of China, 110016 Shenyang, China
| | - Hui Xie
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, China
| | - Hai-Jun Jin
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, China
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Statistics of dislocation avalanches in FCC and BCC metals: dislocation mechanisms and mean swept distances across microsample sizes and temperatures. Sci Rep 2020; 10:19024. [PMID: 33149199 PMCID: PMC7642400 DOI: 10.1038/s41598-020-75934-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 10/19/2020] [Indexed: 11/23/2022] Open
Abstract
Plastic deformation in crystalline materials consists of an ensemble of collective dislocation glide processes, which lead to strain burst emissions in micro-scale samples. To unravel the combined role of crystalline structure, sample size and temperature on these processes, we performed a comprehensive set of strict displacement-controlled micropillar compression experiments in conjunction with large-scale molecular dynamics and physics-based discrete dislocation dynamics simulations. The results indicate that plastic strain bursts consist of numerous individual dislocation glide events, which span over minuscule time intervals. The size distributions of these events exhibit a gradual transition from an incipient power-law slip regime (spanning \documentclass[12pt]{minimal}
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\begin{document}$$\approx$$\end{document}≈ 2.5 decades of slip sizes) to a large avalanche domain (spanning \documentclass[12pt]{minimal}
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\begin{document}$$\approx$$\end{document}≈ 4 decades of emission probability) at a cut-off slip magnitude \documentclass[12pt]{minimal}
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\begin{document}$${s}_{\mathrm{c}}$$\end{document}sc. This cut-off slip provides a statistical measure to the characteristic mean dislocation swept distance, which allows for the scaling of the avalanche distributions vis-à-vis the archetypal dislocation mechanisms in face-centered cubic (FCC) and body-centered cubic (BCC) metals. Our statistical findings provide a new pathway to characterizing metal plasticity and towards comprehension of the sample size effects that limit the mechanical reliability in small-scale structures.
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Samaee V, Gatti R, Devincre B, Pardoen T, Schryvers D, Idrissi H. Dislocation driven nanosample plasticity: new insights from quantitative in-situ TEM tensile testing. Sci Rep 2018; 8:12012. [PMID: 30104742 PMCID: PMC6089927 DOI: 10.1038/s41598-018-30639-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 08/01/2018] [Indexed: 11/21/2022] Open
Abstract
Intrinsic dislocation mechanisms in the vicinity of free surfaces of an almost FIB damage-free single crystal Ni sample have been quantitatively investigated owing to a novel sample preparation method combining twin-jet electro-polishing, in-situ TEM heating and FIB. The results reveal that the small-scale plasticity is mainly controlled by the conversion of few tangled dislocations, still present after heating, into stable single arm sources (SASs) as well as by the successive operation of these sources. Strain hardening resulting from the operation of an individual SAS is reported and attributed to the decrease of the length of the source. Moreover, the impact of the shortening of the dislocation source on the intermittent plastic flow, characteristic of SASs, is discussed. These findings provide essential information for the understanding of the regime of ‘dislocation source’ controlled plasticity and the related mechanical size effect.
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Affiliation(s)
- Vahid Samaee
- Electron Microscop for Materials Science (EMAT), Department of Physics, University of Antwerp, Antwerp, Belgium.
| | - Riccardo Gatti
- Laboratoire d'Etude des Microstructures, UMR104 CNRS-ONERA, 29 av. de la division Leclerc, Chatillon, France
| | - Benoit Devincre
- Laboratoire d'Etude des Microstructures, UMR104 CNRS-ONERA, 29 av. de la division Leclerc, Chatillon, France
| | - Thomas Pardoen
- Institute of Mechanics, Materials and Civil Engineering, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Dominique Schryvers
- Electron Microscop for Materials Science (EMAT), Department of Physics, University of Antwerp, Antwerp, Belgium
| | - Hosni Idrissi
- Electron Microscop for Materials Science (EMAT), Department of Physics, University of Antwerp, Antwerp, Belgium.,Institute of Mechanics, Materials and Civil Engineering, Université catholique de Louvain, Louvain-la-Neuve, Belgium
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6
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Han J, Fang L, Sun J, Han Y, Sun K. Length-dependent mechanical properties of gold nanowires. JOURNAL OF APPLIED PHYSICS 2012; 112:114314. [PMID: 23284186 PMCID: PMC3528680 DOI: 10.1063/1.4768284] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Accepted: 11/06/2012] [Indexed: 05/21/2023]
Abstract
The well-known "size effect" is not only related to the diameter but also to the length of the small volume materials. It is unfortunate that the length effect on the mechanical behavior of nanowires is rarely explored in contrast to the intensive studies of the diameter effect. The present paper pays attention to the length-dependent mechanical properties of 〈111〉-oriented single crystal gold nanowires employing the large-scale molecular dynamics simulation. It is discovered that the ultrashort Au nanowires exhibit a new deformation and failure regime-high elongation and high strength. The constrained dislocation nucleation and transient dislocation slipping are observed as the dominant mechanism for such unique combination of high strength and high elongation. A mechanical model based on image force theory is developed to provide an insight to dislocation nucleation and capture the yield strength and nucleation site of first partial dislocation indicated by simulation results. Increasing the length of the nanowires, the ductile-to-brittle transition is confirmed. And the new explanation is suggested in the predict model of this transition. Inspired by the superior properties, a new approach to strengthen and toughen nanowires-hard/soft/hard sandwich structured nanowires is suggested. A preliminary evidence from the molecular dynamics simulation corroborates the present opinion.
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Kiener D, Kaufmann P, Minor AM. Strength, Hardening, and Failure Observed by In Situ TEM Tensile Testing. ADVANCED ENGINEERING MATERIALS 2012; 14:960-967. [PMID: 23447712 PMCID: PMC3573867 DOI: 10.1002/adem.201200031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Accepted: 04/11/2012] [Indexed: 06/01/2023]
Abstract
We present in situ transmission electron microscope tensile tests on focused ion beam fabricated single and multiple slip oriented Cu tensile samples with thicknesses in the range of 100-200 nm. Both crystal orientations fail by localized shear. While failure occurs after a few percent plastic strain and limited hardening in the single slip case, the multiple slip samples exhibit extended homogenous deformation and necking due to the activation of multiple dislocation sources in conjunction with significant hardening. The hardening behavior at 1% plastic strain is even more pronounced compared to compression samples of the same orientation due to the absence of sample taper and the interface to the compression platen. Moreover, we show for the first time that the strain rate sensitivity of such FIB prepared samples is an order of magnitude higher than that of bulk Cu.
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Affiliation(s)
- Daniel Kiener
- Department of Materials Physics, Montanuniversität Leoben, Jahnstraße 128700 Leoben, Austria
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory94720 Berkeley, CA, USA
| | - Petra Kaufmann
- Department of Materials Physics, Montanuniversität Leoben, Jahnstraße 128700 Leoben, Austria
| | - Andrew M. Minor
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory94720 Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California94720 Berkeley, CA, USA
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8
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Filleter T, Ryu S, Kang K, Yin J, Bernal RA, Sohn K, Li S, Huang J, Cai W, Espinosa HD. Nucleation-controlled distributed plasticity in penta-twinned silver nanowires. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:2986-93. [PMID: 22829327 DOI: 10.1002/smll.201200522] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Indexed: 05/15/2023]
Abstract
A unique size-dependent strain hardening mechanism, that achieves both high strength and ductility, is demonstrated for penta-twinned Ag nanowires (NWs) through a combined experimental-computational approach. Thin Ag NWs are found to deform via the surface nucleation of stacking fault decahedrons (SFDs) in multiple plastic zones distributed along the NW. Twin boundaries lead to the formation of SFD chains that locally harden the NW and promote subsequent nucleation of SFDs at other locations. Due to surface undulations, chain reactions of SFD arrays are activated at stress concentrations and terminated as local stress decreases, revealing insensitivity to defects imparted by the twin structures. Thick NWs exhibit lower flow stress and number of distributed plastic zones due to the onset of necking accompanied by more complex dislocation structures.
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Affiliation(s)
- Tobin Filleter
- Department of Mechanical Engineering, Northwestern University, Evanston IL 60208, USA
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9
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Kiener D, Minor AM. Source truncation and exhaustion: insights from quantitative in situ TEM tensile testing. NANO LETTERS 2011; 11:3816-20. [PMID: 21793497 PMCID: PMC3172822 DOI: 10.1021/nl201890s] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A unique method for quantitative in situ nanotensile testing in a transmission electron microscope employing focused ion beam fabricated specimens was developed. Experiments were performed on copper samples with minimum dimensions in the 100-200 nm regime oriented for either single slip or multiple slip, respectively. We observe that both frequently discussed mechanisms, truncation of spiral dislocation sources and exhaustion of defects available within the specimen, contribute to high strengths and related size-effects in small volumes. This suggests that in the submicrometer range these mechanisms should be considered simultaneously rather than exclusively.
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Affiliation(s)
- D Kiener
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States.
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10
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Jang D, Cai C, Greer JR. Influence of homogeneous interfaces on the strength of 500 nm diameter Cu nanopillars. NANO LETTERS 2011; 11:1743-1746. [PMID: 21388202 DOI: 10.1021/nl2003076] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Interfaces play an important role in crystalline plasticity as they affect strength and often serve as obstacles to dislocation motion. Here we investigate effects of grain and nanotwin boundaries on uniaxial strength of 500 nm diameter Cu nanopillars fabricated by e-beam lithography and electroplating. Uniaxial compression experiments reveal that strength is lowered by introducing grain boundaries and significantly rises when twin boundaries are present. Weakening is likely due to the activation of grain-boundary-mediated processes, while impeding dislocation glide can be responsible for strengthening by twin boundaries.
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Affiliation(s)
- Dongchan Jang
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Passadena, California 91125, United States.
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11
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Bobylev SV, Ovid'ko IA. Nanodisturbances in deformed nanowires. PHYSICAL REVIEW LETTERS 2009; 103:135501. [PMID: 19905521 DOI: 10.1103/physrevlett.103.135501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Indexed: 05/28/2023]
Abstract
A new physical mechanism of plastic deformation in nanowires is suggested and theoretically described. This mechanism represents formation of near-surface nanodisturbances-nanoscopic areas of plastic shear with tiny shear vectors-in deformed nanowires. We calculated the energy characteristics for nanodisturbance formation and compared them with those for conventional dislocation generation. It is shown that the nanodisturbance deformation mode tends to dominate in Au nanowires deformed at high stresses and zero temperature.
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Affiliation(s)
- S V Bobylev
- Institute of Problems of Mechanical Engineering, Russian Academy of Sciences, Vasilievskii Ostrov, St. Petersburg 199178, Russia
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Dutta A, Bhattacharya M, Barat P, Mukherjee P, Gayathri N, Das GC. Lattice resistance to dislocation motion at the nanoscale. PHYSICAL REVIEW LETTERS 2008; 101:115506. [PMID: 18851298 DOI: 10.1103/physrevlett.101.115506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Indexed: 05/26/2023]
Abstract
In this Letter, we propose a model that demonstrates the effect of a free surface on the lattice resistance experienced by a moving dislocation in nanodimensional systems. This effect manifests in an enhanced velocity of dislocation due to the proximity of the dislocation line to the surface. To verify this finding, molecular dynamics simulations for an edge dislocation in bcc molybdenum are performed, and the results are found to be in agreement with the numerical implementations of this model. The reduction in this effect at higher stresses and temperatures, as revealed by the simulations, confirms the role of lattice resistance behind the observed change in the dislocation velocity.
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Affiliation(s)
- A Dutta
- School of Materials Science and Technology, Jadavpur University, Kolkata 700 032, India
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Abstract
Understanding the plasticity and strength of crystalline materials in terms of the dynamics of microscopic defects has been a goal of materials research in the last 70 years. The size-dependent yield stress observed in recent experiments of submicrometer metallic pillars provides a unique opportunity to test our theoretical models, allowing the predictions from defect dynamics simulations to be directly compared with mechanical strength measurements. Although depletion of dislocations from submicrometer face-centered-cubic (FCC) pillars provides a plausible explanation of the observed size-effect, we predict multiplication of dislocations in body-centered-cubic (BCC) pillars through a series of molecular dynamics and dislocation dynamics simulations. Under the combined effects from the image stress and dislocation core structure, a dislocation nucleated from the surface of a BCC pillar generates one or more dislocations moving in the opposite direction before it exits from the surface. The process is repeatable so that a single nucleation event is able to produce a much larger amount of plastic deformation than that in FCC pillars. This self-multiplication mechanism suggests a need for a different explanation of the size dependence of yield stress in FCC and BCC pillars.
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