Fracture toughness of single layer boronitrene sheet using MD simulations

Graphene is a type of 2D material with unique properties and promising applications. Fracture toughness and the tensile strength of a material with cracks are the most important parameters, as micro-cracks are inevitable in the real world. In this paper, we investigated the mechanical properties of triangular-cracked single-layer graphene via molecular dynamics (MD) simulations. The effect of the crack angle, size, temperature, and strain rate on the Young’s modulus, tensile strength, fracture toughness, and fracture strain were examined. We demonstrated that the most vulnerable triangle crack front angle is about 60°. A monitored increase in the crack angle under constant simulation conditions resulted in an enhancement of the mechanical properties. Minor effects on the mechanical properties were obtained under a constant crack shape, constant crack size, and various system sizes. Moreover, the linear elastic characteristics, including fracture toughness, were found to be remarkably influenced by the strain rate variations.

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Mechanical Properties and Fracture Dynamics of Silicene Membranes

MRS Proceedings ◽

10.1557/opl.2013.1055 ◽

2013 ◽

Vol 1549 ◽

pp. 99-107 ◽

Cited By ~ 1

Author(s):

Tiago Botari ◽

Eric Perim ◽

P. A. S. Autreto ◽

Ricardo Paupitz ◽

Douglas S. Galvao

Keyword(s):

Mechanical Properties ◽

Materials Science ◽

Mechanical Strain ◽

Single Layer ◽

Md Simulations ◽

Reactive Force ◽

New Era ◽

Fracture Dynamics ◽

Fracture Patterns ◽

Silicon And Germanium

ABSTRACTThe advent of graphene created a new era in materials science. Graphene is a two-dimensional planar honeycomb array of carbon atoms in sp2-hybridized states. A natural question is whether other elements of the IV-group of the periodic table (such as silicon and germanium), could also form graphene-like structures. Structurally, the silicon equivalent to graphene is called silicene. Silicene was theoretically predicted in 1994 and recently experimentally realized by different groups. Similarly to graphene, silicene exhibits electronic and mechanical properties that can be exploited to nanoelectronics applications.In this work we have investigated, through fully atomistic molecular dynamics (MD) simulations, the mechanical properties of single-layer silicene under mechanical strain. These simulations were carried out using a reactive force field (ReaxFF), as implemented in the LAMMPS code. We have calculated the elastic properties and the fracture patterns.Our results show that the dynamics of the whole fracturing processes of silicene present some similarities with that of graphene as well as some unique features.

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Theoretical Investigation on Failure Strength and Fracture Toughness of Precracked Single-Layer Graphene Sheets

Journal of Nanomaterials ◽

10.1155/2019/9734807 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

Xin-Liang Li ◽

Jian-Gang Guo

Keyword(s):

Fracture Toughness ◽

Fracture Mechanics ◽

Young’S Modulus ◽

Failure Strain ◽

Young's Modulus ◽

Single Layer ◽

Single Layer Graphene ◽

Failure Strength ◽

Griffith Criterion ◽

Variation Trends

Young’s modulus, failure strength, and failure strain of precracked graphene are investigated via finite element method based on molecular structure mechanics in this research. The influence of distribution, length, and orientation of precrack and graphene sizes on these mechanical properties is analyzed. The ratio of precrack length and graphene width is defined as P value, and its particular value Pc can be found, at which the variation trends of Young’s modulus, failure strength, and strain have changes with increasing P value. In addition, the fracture toughness of precracked graphene is investigated, and the stress intensity factor (SIF) is calculated according to the Griffith criterion in classical fracture mechanics. The numerical values of the SIF are about 3.20-3.37 MPa√m, which are compared with the experimental results, and the simulations verify the applicability of the classical fracture mechanics to graphene.

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How the toughness in metallic glasses depends on topological and chemical heterogeneity

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1607506113 ◽

2016 ◽

Vol 113 (26) ◽

pp. 7053-7058 ◽

Cited By ~ 26

Author(s):

Qi An ◽

Konrad Samwer ◽

Marios D. Demetriou ◽

Michael C. Floyd ◽

Danielle O. Duggins ◽

...

Keyword(s):

Fracture Toughness ◽

Metallic Glasses ◽

Energy Barrier ◽

Crack Nucleation ◽

Chemical Separation ◽

Md Simulations ◽

Chemical Heterogeneity ◽

Chemical Inhomogeneity ◽

Critical Factors ◽

Insight Into

To gain insight into the large toughness variability observed between metallic glasses (MGs), we examine the origin of fracture toughness through bending experiments and molecular dynamics (MD) simulations for two binary MGs: Pd82Si18 and Cu46Zr54. The bending experiments show that Pd82Si18 is considerably tougher than Cu46Zr54, and the higher toughness of Pd82Si18 is attributed to an ability to deform plastically in the absence of crack nucleation through cavitation. The MD simulations study the initial stages of cavitation in both materials and extract the critical factors controlling cavitation. We find that for the tougher Pd82Si18, cavitation is governed by chemical inhomogeneity in addition to topological structures. In contrast, no such chemical correlations are observed in the more brittle Cu46Zr54, where topological low coordination number polyhedra are still observed around the critical cavity. As such, chemical inhomogeneity leads to more difficult cavitation initiation in Pd82Si18 than in Cu46Zr54, leading to a higher toughness. The absence of chemical separation during cavitation initiation in Cu46Zr54 decreases the energy barrier for a cavitation event, leading to lower toughness.

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Fracture strength and fracture toughness of graphene: MD simulations

Applied Physics A ◽

10.1007/s00339-021-05047-x ◽

2021 ◽

Vol 127 (12) ◽

Author(s):

V. K. Sutrakar ◽

B. Javvaji ◽

P. R. Budarapu

Keyword(s):

Fracture Toughness ◽

Fracture Strength ◽

Md Simulations

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Wrinkling in Graphene Subjected to Gradient Tension

NANO ◽

10.1142/s179329201550037x ◽

2015 ◽

Vol 10 (03) ◽

pp. 1550037 ◽

Cited By ~ 2

Author(s):

Jianzhang Huang ◽

Qiang Han

Keyword(s):

Molecular Dynamics ◽

Single Layer ◽

Md Simulations ◽

Area Ratio ◽

Single Layer Graphene ◽

Layer Graphene ◽

Out Of Plane ◽

Displacement Direction ◽

Effects Of Temperature ◽

Plane Displacement

In the present study, the initiation and evolution mechanisms of wrinkles in a square single layer graphene sheet (SLGS) under gradient tensile displacements are investigated based on molecular dynamics (MD) simulations. The mechanism of wrinkling process is elucidated by studying the atomic out-of-plane displacements development of the key atoms in SLGS. It reveals that the loading and boundary conditions play dominant roles in the wrinkling deformation of graphene. The dependences of the wrinkling amplitude, wavelength, out-of-plane displacement, direction angle and wrinkling area ratio on the applied gradient tensile displacements are obtained. The effects of temperature, size of graphene and loading grads on graphene wrinkling are investigated.

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Adsorption and Conformational Evolution of Alpha-Helical BSA Segments on Graphene: A Molecular Dynamics Study

International Journal of Applied Mechanics ◽

10.1142/s1758825116500216 ◽

2016 ◽

Vol 08 (02) ◽

pp. 1650021 ◽

Cited By ~ 6

Author(s):

Jingjie Yeo ◽

Yuan Cheng ◽

You Ting Han ◽

Yingyan Zhang ◽

Guijian Guan ◽

...

Keyword(s):

Molecular Dynamics ◽

Conformational Dynamics ◽

Single Layer ◽

Md Simulations ◽

Single Layer Graphene ◽

Strong Interactions ◽

Helical Structures ◽

Single Segment ◽

Helical Content ◽

The Individual

Molecular dynamics (MD) simulations are performed to investigate the adsorption mechanics and conformational dynamics of single and multiple bovine serum albumin (BSA) peptide segments on single-layer graphene through analysis of parameters such as the root-mean-square displacements, number of hydrogen bonds, helical content, interaction energies, and motions of mass center of the peptides. It is found that for the single segment system, destabilization of the helical structures in the form of the reduction in hydrogen bond numbers and [Formula: see text]-helical content of the peptides occurred due to the strong interactions between BSA peptides and graphene. Similar destabilizations of the individual segments in the multi-segment system can occur as well, albeit with greater complexity and in a lesser degree due to the inter-segment interactions. Alleviation of decreases in the total helical content in the multi-segment system indicates protective capabilities of segment–segment interactions, which weaken their interactions with graphene. Diffusive motion upon adsorption of the segment(s) onto graphene is found to be highly confined, and the distance traversed by each segment in the multi-segment system was more significant than that in the single segment system, similarly attributable to reductions in their interactions with graphene due to inter-segment interactions.

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Mechanical Properties of Monolayer Molybdenum Disulfide

Volume 9: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2014-37358 ◽

2014 ◽

Cited By ~ 1

Author(s):

Alireza Tabarraei ◽

Xiaonan Wang ◽

Shohreh Shadalou

Keyword(s):

Mechanical Properties ◽

Molybdenum Disulfide ◽

Density Functional ◽

Single Layer ◽

Md Simulations ◽

Atomistic Simulations ◽

Monolayer Mos2 ◽

Intensity Factors ◽

Functional Theory ◽

Applied Loading

We use atomistic simulations to study mechanical properties of monolayer molybdenum disulfide MoS2. Using molecular dynamic (MD) simulations, we investigate the nano-fracture properties of monolayer MoS2 under mixed mode I and II loadings. The MD simulations are used to obtain the critical stress intensity factors of both armchair and zigzag cracks as a function of applied loading phase angle. Our atomistic simulations predict that armchair cracks are tougher than zigzag cracks, and both armchair and zigzag cracks tend to propagate along a zigzag path. Furthermore, we use density functional theory (DFT) to investigate how point defects influence the mechanical properties of nanoribbons. Our DFT simulations show that missing one S atom does not significantly affect the mechanical strength of monolayer MoS2, whereas missing one Mo atom can reduce the maximum strength of single layer MoS2 sheet by about 10%.

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Elucidating the Mechanical Energy for Cyclization of a DNA Origami Tile

Applied Sciences ◽

10.3390/app11052357 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2357

Author(s):

Ruixin Li ◽

Haorong Chen ◽

Hyeongwoon Lee ◽

Jong Hyun Choi

Keyword(s):

Self Assembly ◽

Mechanical Energy ◽

Single Layer ◽

Md Simulations ◽

Dna Origami ◽

Coarse Grained ◽

Initial Curvature ◽

Coarse Grained Model ◽

Reconfigurable Structures ◽

Computational Platform

DNA origami has emerged as a versatile method to synthesize nanostructures with high precision. This bottom-up self-assembly approach can produce not only complex static architectures, but also dynamic reconfigurable structures with tunable properties. While DNA origami has been explored increasingly for diverse applications, such as biomedical and biophysical tools, related mechanics are also under active investigation. Here we studied the structural properties of DNA origami and investigated the energy needed to deform the DNA structures. We used a single-layer rectangular DNA origami tile as a model system and studied its cyclization process. This origami tile was designed with an inherent twist by placing crossovers every 16 base-pairs (bp), corresponding to a helical pitch of 10.67 bp/turn, which is slightly different from that of native B-form DNA (~10.5 bp/turn). We used molecular dynamics (MD) simulations based on a coarse-grained model on an open-source computational platform, oxDNA. We calculated the energies needed to overcome the initial curvature and induce mechanical deformation by applying linear spring forces. We found that the initial curvature may be overcome gradually during cyclization and a total of ~33.1 kcal/mol is required to complete the deformation. These results provide insights into the DNA origami mechanics and should be useful for diverse applications such as adaptive reconfiguration and energy absorption.

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