The Experts below are selected from a list of 8922 Experts worldwide ranked by ideXlab platform

Yonggang Huang - One of the best experts on this subject based on the ideXlab platform.

  • A Cohesive Law for interfaces between multi-wall carbon nanotubes and polymers due to the van der Waals interactions
    Computer Methods in Applied Mechanics and Engineering, 2007
    Co-Authors: Jizhou Song, Liying Jiang, Keh Chih Hwang, Yonggang Huang
    Abstract:

    We have established the Cohesive Law for interfaces between multi-wall carbon nanotubes (CNTs) and polymer that are not well bonded and are characterized by the van der Waals force. The Cohesive Law is obtained in terms of the area density of carbon atoms on CNT walls, number of CNT walls, volume density of CH2 units in the polymer, and parameters in the van der Waals force. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between multi-wall CNTs and polymer, such as in CNT-reinforced composites.

  • the effect of van der waals based interface Cohesive Law on carbon nanotube reinforced composite materials
    Composites Science and Technology, 2007
    Co-Authors: Liying Jiang, Yonggang Huang, Kuo Chu Hwang
    Abstract:

    Abstract The nonlinear Cohesive Law derived from the weak van der Waals force for carbon nanotube/polymer interfaces is incorporated in present study of CNT-reinforced composites. Carbon nanotubes can indeed improve the mechanical behavior of composite at the small strain, but such improvement disappears at relatively large strain because the completely debonded nanotubes behave like voids in the matrix and may even weaken the composite. The increase of interface adhesion between carbon nanotubes and polymer-matrix may significantly improve the composite behavior at the large strain.

  • A Cohesive Law for multi-wall carbon nanotubes
    Philosophical Magazine, 2007
    Co-Authors: Liying Jiang, Yonggang Huang, Kuo Chu Hwang, Bo Liu
    Abstract:

    We have established the Cohesive Law for carbon nanotube (CNT) walls in multi-wall CNTs. The interactions between CNT walls are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of CNT and parameters in the van der Waals force. For an infinitely long CNT, the shear Cohesive stress between CNT walls vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a finite CNT, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e. the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between walls in multi-wall CNTs.

  • a Cohesive Law for carbon nanotube polymer interfaces based on the van der waals force
    Journal of The Mechanics and Physics of Solids, 2006
    Co-Authors: Liying Jiang, Yonggang Huang, Keh Chih Hwang, Hanqing Jiang, G. Ravichandran, Huajian Gao, Bin Liu
    Abstract:

    We have established the Cohesive Law for interfaces between a carbon nanotube (CNT) and polymer that are not well bonded and are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of carbon nanotube and volume density of polymer, as well as the parameters in the van der Waals force. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a CNT in a finite polymer matrix, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e., the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between CNT and polymer, such as in CNT-reinforced composites. The effect of polymer surface roughness on the Cohesive Law is also studied.

  • A Cohesive Law for carbon nanotube/polymer interfaces based on the van der Waals force
    Journal of the Mechanics and Physics of Solids, 2006
    Co-Authors: Liying Jiang, Yonggang Huang, Keh Chih Hwang, Hanqing Jiang, G. Ravichandran, Huajian Gao, Bin Liu
    Abstract:

    We have established the Cohesive Law for interfaces between a carbon nanotube (CNT) and polymer that are not well bonded and are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of carbon nanotube and volume density of polymer, as well as the parameters in the van der Waals force. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a CNT in a finite polymer matrix, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e., the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between CNT and polymer, such as in CNT-reinforced composites. The effect of polymer surface roughness on the Cohesive Law is also studied.

Liying Jiang - One of the best experts on this subject based on the ideXlab platform.

  • A Cohesive Law for Carbon Nanotube/Polymer Interface Accounting for Chemical Covalent Bonds
    Mathematics and Mechanics of Solids, 2010
    Co-Authors: Liying Jiang
    Abstract:

    The influence of chemical bonds formed between a single-walled carbon nanotube (CNT) and a polymer matrix upon the interface behavior has been studied through the development of an interfacial Cohesive Law. By using the interatomic potential directly, the tensile Cohesive stress and Cohesive energy for the interface with opening mode separation are expressed in terms of the area density of the carbon atoms of the CNT, the volume density of the polymer molecules, the material constants of the CNT and the polymer matrix, the parameters in the van der Waals potential, and the Brenner potential and the chemical bond density. This Cohesive Law avoids any phenomenological assumption between the normal traction and interface opening displacement. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. The Cohesive properties, such as the total Cohesive energy, have increased significantly, which results in a stronger interfac...

  • a Cohesive Law for carbon nanotube polymer interface accounting for chemical covalent bonds
    Mathematics and Mechanics of Solids, 2010
    Co-Authors: Liying Jiang
    Abstract:

    The influence of chemical bonds formed between a single-walled carbon nanotube (CNT) and a polymer matrix upon the interface behavior has been studied through the development of an interfacial Cohesive Law. By using the interatomic potential directly, the tensile Cohesive stress and Cohesive energy for the interface with opening mode separation are expressed in terms of the area density of the carbon atoms of the CNT, the volume density of the polymer molecules, the material constants of the CNT and the polymer matrix, the parameters in the van der Waals potential, and the Brenner potential and the chemical bond density. This Cohesive Law avoids any phenomenological assumption between the normal traction and interface opening displacement. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. The Cohesive properties, such as the total Cohesive energy, have increased significantly, which results in a stronger interfac...

  • A Cohesive Law for interfaces between multi-wall carbon nanotubes and polymers due to the van der Waals interactions
    Computer Methods in Applied Mechanics and Engineering, 2007
    Co-Authors: Jizhou Song, Liying Jiang, Keh Chih Hwang, Yonggang Huang
    Abstract:

    We have established the Cohesive Law for interfaces between multi-wall carbon nanotubes (CNTs) and polymer that are not well bonded and are characterized by the van der Waals force. The Cohesive Law is obtained in terms of the area density of carbon atoms on CNT walls, number of CNT walls, volume density of CH2 units in the polymer, and parameters in the van der Waals force. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between multi-wall CNTs and polymer, such as in CNT-reinforced composites.

  • the effect of van der waals based interface Cohesive Law on carbon nanotube reinforced composite materials
    Composites Science and Technology, 2007
    Co-Authors: Liying Jiang, Yonggang Huang, Kuo Chu Hwang
    Abstract:

    Abstract The nonlinear Cohesive Law derived from the weak van der Waals force for carbon nanotube/polymer interfaces is incorporated in present study of CNT-reinforced composites. Carbon nanotubes can indeed improve the mechanical behavior of composite at the small strain, but such improvement disappears at relatively large strain because the completely debonded nanotubes behave like voids in the matrix and may even weaken the composite. The increase of interface adhesion between carbon nanotubes and polymer-matrix may significantly improve the composite behavior at the large strain.

  • A Cohesive Law for multi-wall carbon nanotubes
    Philosophical Magazine, 2007
    Co-Authors: Liying Jiang, Yonggang Huang, Kuo Chu Hwang, Bo Liu
    Abstract:

    We have established the Cohesive Law for carbon nanotube (CNT) walls in multi-wall CNTs. The interactions between CNT walls are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of CNT and parameters in the van der Waals force. For an infinitely long CNT, the shear Cohesive stress between CNT walls vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a finite CNT, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e. the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between walls in multi-wall CNTs.

Lincy Pyl - One of the best experts on this subject based on the ideXlab platform.

  • quasi static crush modelling of carbon epoxy composites with discontinuous galerkin anisotropic extrinsic Cohesive Law method
    Composite Structures, 2019
    Co-Authors: Xing Liu, Danny Van Hemelrijck, Lincy Pyl
    Abstract:

    Abstract Carbon/epoxy composites demonstrate significant promising improvements of weight to performance in the automotive industry. However, the design of carbon/epoxy composite components for crashworthiness remains challenging and normally requires laborious and repeated experimental work. This study adopts a predictive crush model of carbon/epoxy composites, which can partially replace the experimental work. The discontinuous Galerkin (DG) method with extrinsic Cohesive Laws is employed to simulate the failure patterns in the composite structures. The application of DG distinguishes the fracture model from the conventional approach where preset Cohesive elements are used on the location where cracks are expected. The mixed mode Cohesive Laws are used to simulate the delamination between each layer. To capture different crack propagations in different layups, the anisotropic Cohesive Law is used to simulate the intralaminar crack propagation in composites. To verify the adopted model, circular composite tube specimens with different layups have been simulated and compared with tests under quasi-static crush loadings. The comparisons of numerical results with experimental data show that the DG crush model can reproduce the experimental results with relatively high accuracy.

  • Quasi-static crush modelling of carbon/epoxy composites with discontinuous Galerkin/anisotropic extrinsic Cohesive Law method
    Composite Structures, 2019
    Co-Authors: Xing Liu, Danny Van Hemelrijck, Lincy Pyl
    Abstract:

    Abstract Carbon/epoxy composites demonstrate significant promising improvements of weight to performance in the automotive industry. However, the design of carbon/epoxy composite components for crashworthiness remains challenging and normally requires laborious and repeated experimental work. This study adopts a predictive crush model of carbon/epoxy composites, which can partially replace the experimental work. The discontinuous Galerkin (DG) method with extrinsic Cohesive Laws is employed to simulate the failure patterns in the composite structures. The application of DG distinguishes the fracture model from the conventional approach where preset Cohesive elements are used on the location where cracks are expected. The mixed mode Cohesive Laws are used to simulate the delamination between each layer. To capture different crack propagations in different layups, the anisotropic Cohesive Law is used to simulate the intralaminar crack propagation in composites. To verify the adopted model, circular composite tube specimens with different layups have been simulated and compared with tests under quasi-static crush loadings. The comparisons of numerical results with experimental data show that the DG crush model can reproduce the experimental results with relatively high accuracy.

Bin Liu - One of the best experts on this subject based on the ideXlab platform.

  • a Cohesive Law for carbon nanotube polymer interfaces based on the van der waals force
    Journal of The Mechanics and Physics of Solids, 2006
    Co-Authors: Liying Jiang, Yonggang Huang, Keh Chih Hwang, Hanqing Jiang, G. Ravichandran, Huajian Gao, Bin Liu
    Abstract:

    We have established the Cohesive Law for interfaces between a carbon nanotube (CNT) and polymer that are not well bonded and are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of carbon nanotube and volume density of polymer, as well as the parameters in the van der Waals force. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a CNT in a finite polymer matrix, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e., the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between CNT and polymer, such as in CNT-reinforced composites. The effect of polymer surface roughness on the Cohesive Law is also studied.

  • A Cohesive Law for carbon nanotube/polymer interfaces based on the van der Waals force
    Journal of the Mechanics and Physics of Solids, 2006
    Co-Authors: Liying Jiang, Yonggang Huang, Keh Chih Hwang, Hanqing Jiang, G. Ravichandran, Huajian Gao, Bin Liu
    Abstract:

    We have established the Cohesive Law for interfaces between a carbon nanotube (CNT) and polymer that are not well bonded and are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of carbon nanotube and volume density of polymer, as well as the parameters in the van der Waals force. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a CNT in a finite polymer matrix, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e., the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between CNT and polymer, such as in CNT-reinforced composites. The effect of polymer surface roughness on the Cohesive Law is also studied.

Keh Chih Hwang - One of the best experts on this subject based on the ideXlab platform.

  • A Cohesive Law for interfaces between multi-wall carbon nanotubes and polymers due to the van der Waals interactions
    Computer Methods in Applied Mechanics and Engineering, 2007
    Co-Authors: Jizhou Song, Liying Jiang, Keh Chih Hwang, Yonggang Huang
    Abstract:

    We have established the Cohesive Law for interfaces between multi-wall carbon nanotubes (CNTs) and polymer that are not well bonded and are characterized by the van der Waals force. The Cohesive Law is obtained in terms of the area density of carbon atoms on CNT walls, number of CNT walls, volume density of CH2 units in the polymer, and parameters in the van der Waals force. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between multi-wall CNTs and polymer, such as in CNT-reinforced composites.

  • a Cohesive Law for carbon nanotube polymer interfaces based on the van der waals force
    Journal of The Mechanics and Physics of Solids, 2006
    Co-Authors: Liying Jiang, Yonggang Huang, Keh Chih Hwang, Hanqing Jiang, G. Ravichandran, Huajian Gao, Bin Liu
    Abstract:

    We have established the Cohesive Law for interfaces between a carbon nanotube (CNT) and polymer that are not well bonded and are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of carbon nanotube and volume density of polymer, as well as the parameters in the van der Waals force. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a CNT in a finite polymer matrix, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e., the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between CNT and polymer, such as in CNT-reinforced composites. The effect of polymer surface roughness on the Cohesive Law is also studied.

  • A Cohesive Law for carbon nanotube/polymer interfaces based on the van der Waals force
    Journal of the Mechanics and Physics of Solids, 2006
    Co-Authors: Liying Jiang, Yonggang Huang, Keh Chih Hwang, Hanqing Jiang, G. Ravichandran, Huajian Gao, Bin Liu
    Abstract:

    We have established the Cohesive Law for interfaces between a carbon nanotube (CNT) and polymer that are not well bonded and are characterized by the van der Waals force. The tensile Cohesive strength and Cohesive energy are given in terms of the area density of carbon nanotube and volume density of polymer, as well as the parameters in the van der Waals force. For a CNT in an infinite polymer, the shear Cohesive stress vanishes, and the tensile Cohesive stress depends only on the opening displacement. For a CNT in a finite polymer matrix, the tensile Cohesive stress remains the same, but the shear Cohesive stress depends on both opening and sliding displacements, i.e., the tension/shear coupling. The simple, analytical expressions of the Cohesive Law are useful to study the interaction between CNT and polymer, such as in CNT-reinforced composites. The effect of polymer surface roughness on the Cohesive Law is also studied.