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Buckling Strain
The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
C Q Ru – 1st expert on this subject based on the ideXlab platform
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Curvature effects on axially compressed Buckling of a small-diameter double-walled carbon nanotube
International Journal of Solids and Structures, 2005Co-Authors: H. Qian, K. Y. Xu, C Q RuAbstract:Abstract The curvature effects of interlayer van der Waals (vdW) forces on axially compressed Buckling of a double-walled carbon nanotube (DWNT) of diameter down to 0.7 nm are studied. Unlike most existing models which assume that the interlayer vdW pressure at a point between the inner and outer tubes depends merely on the change of the interlayer spacing at that point, the present model considers the dependence of the interlayer vdW pressure on the change of the curvatures of the inner and outer tubes at that point. A simple expression is derived for the curvature-dependence of the interlayer vdW pressure in which the curvature coefficient is determined. Based on this model, an explicit formula is obtained for the axial Buckling Strain. It is shown that neglecting the curvature effect alone leads to an under-estimate of the critical Buckling Strain with a relative error up to −7%, while taking the average radius of two tubes as the representative radius and the curvature effect leads to an over-estimate of the critical Buckling Strain with a relative error up to 20% when the inner radius downs to 0.35 nm. Therefore, the curvature effects play a significant role in axially compressed Buckling problems only for DWNTs of very small radii. In addition, our results show that the effect of the vdW interaction pressure prior to Buckling of DWNTs under pure axial stress is small enough and can be negligible whether the vdW interaction curvature effects are neglected or not.
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degraded axial Buckling Strain of multiwalled carbon nanotubes due to interlayer slips
Journal of Applied Physics, 2001Co-Authors: C Q RuAbstract:A multiple-shell model is presented for infinitesimal axially compressed Buckling of a multiwalled carbon nanotube embedded within an elastic matrix. In contrast to an existing single-shell model which treats the entire multiwalled nanotube as a singlelayer elastic shell, the present model assumes that each of the nested concentric tubes is an individual elastic shell and the deflections of all shells are coupled through the van der Waals interaction between adjacent nanotubes. By examining a doublewalled carbon nanotube, it is found that the change in interlayer spacing has a negligible effect on the axial Buckling Strain provided that the innermost radius is at least a few nanometers. Under this condition, a single equation is derived which determines the deflection of the multiwalled carbon nanotube, and it is shown that infinitesimal axial Buckling of a N-walled carbon nanotubes is equivalent to that of a single layer elastic shell whose bending stiffness is approximately N times the effective bending…
Otto Zhou – 2nd expert on this subject based on the ideXlab platform
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Deformation of carbon nanotubes in nanotube–polymer composites
Applied Physics Letters, 1999Co-Authors: Christopher A. Bower, R. Rosen, Otto ZhouAbstract:Composites of uniaxially oriented multiwalled carbon nanotubes embedded in polymer matrices were fabricated and investigated by transmission electron microscopy. In Strained composite films, Buckling was ubiquitously observed in bent nanotubes with large curvatures. By analyses of a large number of bent nanotubes, the onset Buckling Strain and fracture Strain were estimated to be ≈5% and ⩾18%, respectively. The Buckling wavelengths are proportional to the dimensions of the nanotubes. Examination of the fracture surface showed adherence of the polymer to the nanotubes.
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Deformation of carbon nanotubes in nanotube-polymer composites
Applied Physics Letters, 1999Co-Authors: Chris Bower, R. Rosen, L. Jin, J Han, Otto ZhouAbstract:Composites of uniaxially oriented multiwalled carbon nanotubes embedded in polymer matrices were fabricated and investigated by transmission electron microscopy. In Strained composite films, Buckling was ubiquitously observed in bent nanotubes with large curvatures. By analyses of a large number of bent nanotubes, the onset Buckling Strain and fracture Strain were estimated to be ≈5% and ⩾18%, respectively. The Buckling wavelengths are proportional to the dimensions of the nanotubes. Examination of the fracture surface showed adherence of the polymer to the nanotubes.
Quan Wang – 3rd expert on this subject based on the ideXlab platform
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Buckling and Vibration of Carbon Nanotubes Embedded in Polyethylene Polymers
Applied Mechanics and Materials, 2011Co-Authors: Quan WangAbstract:The discovery of Buckling instability and vibration of polyethylene/ carbon nanotube matrices is reported by molecular mechanics simulations. The research is aimed to acquire a high strength design of PE-CNT matrix with proper PE/CNT ratio as well as discovering the dynamic characteristics of the PE-CNT composites. The Buckling Strains and the resonance frequencies are found to decrease with an increase in the number of polyethylene chains in the polyethylene/carbon nanotube matrices. Van der Waals forces are collected to explain the relation of the PE chains to the Buckling Strain and the resonance frequency of the composites.
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Compressive Buckling of carbon nanotubes containing polyethylene molecules
Carbon, 2011Co-Authors: Quan WangAbstract:The instability of a carbon nanotube containing a polyethylene molecule subjected to compression is investigated using molecular dynamics. A decrease up to 35% in the Buckling Strain of the (6,6) and (10,10) carbon nanotube/polymer structures due to the attractive van der Waals interaction between the tube wall and the polymer molecule is reported. In particular, the decrease in the Buckling Strain of the (6,6) carbon nanotube/polymer structure is attributed to the initiation of two flattenings on the tube wall. Simulations show that the Buckling Strain of the structure is insensitive to the number of units of the polymer molecule.
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Buckling of carbon nanotubes wrapped by polyethylene molecules
Physics Letters A, 2011Co-Authors: Quan WangAbstract:Abstract The discovery of a Buckling instability of a single-walled carbon nanotube wrapped by a polyethylene molecule subjected to compression is reported through molecular mechanics simulations. A decrease up to 44% in the Buckling Strain of the nano-structure owing to the van der Waals interaction between the two molecules is uncovered. A continuum model is developed to calculate both the interaction between the tube and the polymer and the decreased Buckling Strain of the structure by fitting the molecular mechanics results.