Mechanical Response of Carbon Nanotube Bundle to Lateral Compression

Structure evolution and mechanical response of the carbon nanotube (CNT) bundle under lateral biaxial compression is investigated in plane strain conditions using the chain model. In this model, tensile and bending rigidity of CTN walls, and the van der Waals interactions between them are taken into account. Initially the bundle in cross section is a triangular lattice of circular zigzag CNTs. Under increasing strain control compression, several structure transformations are observed. Firstly, the second-order phase transition leads to the crystalline structure with doubled translational cell. Then the first-order phase transition takes place with the appearance of collapsed CNTs. Further compression results in increase of the fraction of collapsed CNTs at nearly constant compressive stress and eventually all CNTs collapse. It is found that the potential energy of the CNT bundle during deformation changes mainly due to bending of CNT walls, while the contribution from the walls tension-compression and from the van der Waals energies is considerably smaller.

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ELASTIC DAMPER BASED ON THE CARBON NANOTUBE BUNDLE

Facta Universitatis Series Mechanical Engineering ◽

10.22190/fume200128011r ◽

2020 ◽

Vol 18 (1) ◽

pp. 001 ◽

Cited By ~ 2

Author(s):

Leysan Kh. Rysaeva ◽

Elena A. Korznikova ◽

Ramil T. Murzaev ◽

Dina U. Abdullina ◽

Aleksey A. Kudreyko ◽

...

Keyword(s):

Phase Transition ◽

Carbon Nanotube ◽

Order Phase Transition ◽

Degrees Of Freedom ◽

High Efficiency ◽

Mechanical Response ◽

Compressive Strain ◽

Period Doubling ◽

Chain Model ◽

Nanotube Bundle

Mechanical response of the carbon nanotube bundle to uniaxial and biaxial lateral compression followed by unloading is modeled under plane strain conditions. The chain model with a reduced number of degrees of freedom is employed with high efficiency. During loading, two critical values of strain are detected. Firstly, period doubling is observed as a result of the second order phase transition, and at higher compressive strain, the first order phase transition takes place when carbon nanotubes start to collapse. The loading-unloading stress-strain curves exhibit a hysteresis loop and, upon unloading, the structure returns to its initial form with no residual strain. This behavior of the nanotube bundle can be employed for the design of an elastic damper.

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Chain Model for Carbon Nanotube Bundle under Plane Strain Conditions

Materials ◽

10.3390/ma12233951 ◽

2019 ◽

Vol 12 (23) ◽

pp. 3951 ◽

Cited By ~ 6

Author(s):

Elena A. Korznikova ◽

Leysan Kh. Rysaeva ◽

Alexander V. Savin ◽

Elvira G. Soboleva ◽

Evgenii G. Ekomasov ◽

...

Keyword(s):

Mechanical Properties ◽

Plane Strain ◽

Degrees Of Freedom ◽

High Pressures ◽

Mechanical Response ◽

Solid Lubricants ◽

Equilibrium Structure ◽

Van Der Waals Interactions ◽

Chain Model ◽

Bending Rigidity

Carbon nanotubes (CNTs) have record high tensile strength and Young’s modulus, which makes them ideal for making super strong yarns, ropes, fillers for composites, solid lubricants, etc. The mechanical properties of CNT bundles have been addressed in a number of experimental and theoretical studies. The development of efficient computational methods for solving this problem is an important step in the design of new CNT-based materials. In the present study, an atomistic chain model is proposed to analyze the mechanical response of CNT bundles under plane strain conditions. The model takes into account the tensile and bending rigidity of the CNT wall, as well as the van der Waals interactions between walls. Due to the discrete character of the model, it is able to describe large curvature of the CNT wall and the fracture of the walls at very high pressures, where both of these problems are difficult to address in frame of continuum mechanics models. As an example, equilibrium structures of CNT crystal under biaxial, strain controlled loading are obtained and their thermal stability is analyzed. The obtained results agree well with previously reported data. In addition, a new equilibrium structure with four SNTs in a translational cell is reported. The model offered here can be applied with great efficiency to the analysis of the mechanical properties of CNT bundles composed of single-walled or multi-walled CNTs under plane strain conditions due to considerable reduction in the number of degrees of freedom.

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Nematic first order phase transition for liquid crystals in the van der Waals–Kac limit

Journal of Mathematical Physics ◽

10.1063/5.0007613 ◽

2020 ◽

Vol 61 (10) ◽

pp. 103306

Author(s):

Clément Erignoux ◽

Alessandro Giuliani

Keyword(s):

Phase Transition ◽

Liquid Crystals ◽

Order Phase Transition ◽

Van Der Waals ◽

First Order ◽

First Order Phase Transition ◽

First Order Phase

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EVOLUTION OF THE CARBON NANOTUBE BUNDLE STRUCTURE UNDER BIAXIAL AND SHEAR STRAINS

Facta Universitatis Series Mechanical Engineering ◽

10.22190/fume201005043r ◽

2020 ◽

pp. 525

Author(s):

Leysan Kh. Rysaeva ◽

Dmitry V. Bachurin ◽

Ramil T. Murzaev ◽

Dina U. Abdullina ◽

Elena A. Korznikova ◽

...

Keyword(s):

Carbon Nanotube ◽

Shear Strain ◽

Cross Sections ◽

Degrees Of Freedom ◽

Shear Bands ◽

Volumetric Strain ◽

Structural Evolution ◽

Biaxial Compression ◽

Chain Model ◽

Nanotube Bundle

Close packed carbon nanotube bundles are materials with highly deformable elements, for which unusual deformation mechanisms are expected. Structural evolution of the zigzag carbon nanotube bundle subjected to biaxial lateral compression with the subsequent shear straining is studied under plane strain conditions using the chain model with a reduced number of degrees of freedom. Biaxial compression results in bending of carbon nanotubes walls and formation of the characteristic pattern, when nanotube cross-sections are inclined in the opposite directions alternatively in the parallel close-packed rows. Subsequent shearing up to a certain shear strain leads to an appearance of shear bands and vortex-like displacements. Stress components and potential energy as the functions of shear strain for different values of the biaxial volumetric strain are analyzed in detail. A new mechanism of carbon nanotube bundle shear deformation through cooperative, vortex-like displacements of nanotube cross sections is reported.

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Insight into the effect of methylated urea on the phase transition of aqueous solutions of poly(N -isopropylacrylamide) by microcalorimetry: Hydrogen bonding and van der Waals interactions

Journal of Polymer Science Part B Polymer Physics ◽

10.1002/polb.24018 ◽

2016 ◽

Vol 54 (12) ◽

pp. 1145-1151 ◽

Cited By ~ 3

Author(s):

Yating Gao ◽

Jinxian Yang ◽

Haiyan Fan ◽

Yanwei Ding ◽

Xiaodong Ye

Keyword(s):

Phase Transition ◽

Hydrogen Bonding ◽

Aqueous Solutions ◽

Van Der Waals ◽

Van Der Waals Interactions ◽

Insight Into

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Holographic van der Waals Phase Transition for a Hairy Black Hole

Advances in High Energy Physics ◽

10.1155/2017/2356174 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Xiao-Xiong Zeng ◽

Yi-Wen Han

Keyword(s):

Phase Transition ◽

Black Hole ◽

Order Phase Transition ◽

Phase Structure ◽

Van Der Waals ◽

Thermal Entropy ◽

First Order Phase Transition ◽

Geodesic Length ◽

First Order Phase ◽

Hairy Black Hole

The van der Waals (VdW) phase transition in a hairy black hole is investigated by analogizing its charge, temperature, and entropy as the temperature, pressure, and volume in the fluid, respectively. The two-point correlation function (TCF), which is dual to the geodesic length, is employed to probe this phase transition. We find the phase structure in the temperature-thermal entropy plane besides the scale of the horizontal coordinate (geodesic length plane resembles that in the temperature). In addition, we find the equal area law (EAL) for the first-order phase transition and critical exponent of the heat capacity for the second-order phase transition in the temperature-thermal entropy plane (geodesic length plane is consistent with that in temperature), which implies that the TCF is a good probe to probe the phase structure of the back hole.

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