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Jizhou Song - One of the best experts on this subject based on the ideXlab platform.

  • Buckling of a stiff thin film on a bi-layer compliant substrate of finite thickness
    International Journal of Solids and Structures, 2020
    Co-Authors: Chengjun Wang, Zhang Shun, Shuang Nie, Weiqiu Chen, Jizhou Song
    Abstract:

    Abstract The Buckling of a stiff thin film on a compliant substrate has been widely studied over the past decade due to its wide applications such as stretchable electronics, micro- and nano-metrology, and surface engineering. Instead of a single-layer compliant substrate, a bi-layer compliant substrate is usually encountered in practical applications. In this paper, the Buckling of a stiff thin film on a bi-layer compliant substrate of finite thickness is studied theoretically, numerically and experimentally. The theoretical models based on the small-deformation theory and the simple finite-deformation theory accounting for the geometry change by using the energy method are both developed and presented. The good agreement among theoretical predictions, finite element analysis and experimental measurements of the Buckling behavior validates the theoretical model. The influences of finite thickness of the bi-layer substrate and substrate modulus ratio on the Buckling wavelength and Critical Buckling Strain are systematically investigated. The Buckling configurations at various applied Strains are also measured to further validate the theoretical model. These results shed light on the influence of finite substrate thickness on Buckling of the bi-layer substrate-supported thin films and are helpful to provide design guidelines in practical applications.

  • Buckling of a stiff thin film on an elastic graded compliant substrate
    Proceedings of The Royal Society A: Mathematical Physical and Engineering Sciences, 2017
    Co-Authors: Zhou Chen, Weiqiu Chen, Jizhou Song
    Abstract:

    The Buckling of a stiff film on a compliant substrate has attracted much attention due to its wide applications such as thin-film metrology, surface patterning and stretchable electronics. An analytical model is established for the Buckling of a stiff thin film on a semi-infinite elastic graded compliant substrate subjected to in-plane compression. The Critical compressive Strain and Buckling wavelength for the sinusoidal mode are obtained analytically for the case with the substrate modulus decaying exponentially. The rigorous finite element analysis (FEA) is performed to validate the analytical model and investigate the postBuckling behaviour of the system. The Critical Buckling Strain for the period-doubling mode is obtained numerically. The influences of various material parameters on the results are investigated. These results are helpful to provide physical insights on the Buckling of elastic graded substrate-supported thin film.

  • Surface effects on the wrinkles in a stiff thin film bonded to a compliant substrate
    Thin Solid Films, 2012
    Co-Authors: Yuhang Li, Jiazhong Zhang, Bo Fang, Jizhou Song
    Abstract:

    Abstract Surface effects are important to predict the mechanical behavior of nanostructures. In this paper, the wrinkling of a stiff thin film bonded to a compliant substrate is studied using an energy method accounting for surface elasticity and residual surface tension. The wavelength, Critical Buckling Strain and amplitude are obtained analytically. These results provide valuable guide to the precise design and control of the wrinkling profile in many applications ranging from stretchable electronics to micro/nano scale surface patterning and precision metrology.

Xi Chen - One of the best experts on this subject based on the ideXlab platform.

  • Buckling patterns of thin films on compliant substrates the effect of plasticity
    Journal of Physics D, 2011
    Co-Authors: Jie Yin, Xi Chen
    Abstract:

    Most previous studies on spontaneous Buckling pattern formations in thin films on compliant substrates were limited to elastic deformation, where the herringbone mode is the most often observed under equi-biaxial compression. In practice, plastic deformation is often encountered in ductile metal and polymer films. The effect of plasticity on Buckling patterns is explored in this paper using extensive finite element simulations, where the film is assumed to be elastic–perfectly plastic. It is found that upon equi-biaxial compression, depending on the competition among the yield Strain, Critical Buckling Strain and applied Strain, three new types of patterns may emerge: the plastic diamond-like pattern, the elastoplastic square lattice pattern and the elastoplastic sharp herringbone pattern, and their characteristics are compared with the elastic herringbone mode. Moreover, unique features including the asymmetry in crests and troughs, the sharp saw-like undulation profile and varying wavelengths with applied Strain are observed for some types of the new patterns. The study may find its potential applications in the design of stretchable electronics, fabrication of micro/nanofluid channels or channel networks, and morphogenesis of tissues and plants, among others.

  • The effect of the displacement increment on the axial compressive Buckling behaviours of single-walled carbon nanotubes
    Nanotechnology, 2006
    Co-Authors: Xi Chen
    Abstract:

    We carry out systematic molecular mechanics (MM) analyses to study the effect of the displacement increment on the Critical Buckling Strain of single-walled carbon nanotubes (SWCNTs) under axial compression. The SWCNT geometric parameters, such as the tube length, diameter, and chirality, are varied in the numerical studies. The results show that the Critical Buckling Strain of the SWCNTs deduced from the atomistic analyses is highly sensitive to the displacement increment used in the numerical simulation, and such an effect is more obvious for tubes with smaller diameters. Therefore, a reasonable compressive displacement increment should be selected in the atomistic simulations in order to obtain the intrinsic values of the Critical Buckling Strain, which is suggested in this paper. The studies in this paper may be used to explain the contradicting results of the Critical compressive Buckling Strains computed by other MM analyses in the literature.

Zhixin Chen - One of the best experts on this subject based on the ideXlab platform.

  • Research on the Critical Buckling Strain Criterion for Pipelines
    2008 7th International Pipeline Conference Volume 3, 2008
    Co-Authors: Hua Zhang, Xinwei Zhao, Guangli Zhang, Zhixin Chen
    Abstract:

    The local Buckling of pipelines is regarded as a kind of failure. The Critical Buckling Strain is an important parameter in Strain-based design of pipelines. According to the grey system theory, the factors affecting the Critical Buckling Strain were analyzed and the correlation between these factors and the Critical Buckling Strain was quantitatively measured based on test data. According to the dimension analysis theory, the factors affecting the Critical Buckling Strain were analyzed and the correlation between the factors and a new Critical Buckling Strain equation was proposed based on test data. And some advice was provided for the improvement of Critical Buckling Strain equations. Comparing the results with data from full scale tests, these as-obtained equations could provide a higher precision.Copyright © 2008 by ASME

Samer Adeeb - One of the best experts on this subject based on the ideXlab platform.

  • the effect of material stress Strain characteristics on the ultimate stress and Critical Buckling Strain of flat plates subjected to uniform axial compression
    Construction and Building Materials, 2018
    Co-Authors: Onyekachi Ndubuaku, Michael Martens, J Roger J Cheng, Samer Adeeb
    Abstract:

    Abstract The Buckling capacity of uniformly compressed flat plates has been investigated in this study. Material properties were characterized based on parameterization of the stress-Strain curves using a simple and novel mathematical expression. Idealized stress-Strain relationships were developed using the proposed material model and extensive parametric numerical analyses were conducted to investigate the effect of the material stress-Strain properties on the Buckling capacity of flat plates. For stress-Strain curves with a yield plateau, the results of the parametric study showed a minimal influence of the material properties on the Buckling capacity of the plates whereas a significant effect of the Strain-hardening properties was observed in plates with round-house curves. Ultimately, the proposed stress-Strain model was shown to be remarkably useful for capturing the relevant intricacies associated with material nonlinearity when predicting the Buckling capacity and post-Buckling behavior of uniformly-compressed flat plates.

  • Critical Buckling Strain in high strength steel pipes using isotropic kinematic hardening
    2010 8th International Pipeline Conference Volume 4, 2010
    Co-Authors: A. Fathi, J Roger J Cheng, Samer Adeeb, Joe Zhou
    Abstract:

    High strength steel pipes (HSSP) have become more popular recently for highly pressurized pipelines built to transport natural gas from remote fields to energy markets. Material tests on HSSP showed significant material anisotropy caused by the pipe making process, UOE. A combined isotropic-kinematic hardening material model is developed based on observations made on longitudinal and transverse stress Strain data of HSSP. This material model combines linear isotropic hardening with Armstrong-Fredrick kinematic hardening and can be easily calibrated by longitudinal and transverse tension coupon test results. The proposed material model is used to show how considering material anisotropy affects the Critical Buckling Strain of HSSP in the longitudinal direction. Finite element (FE) models are developed to simulate one pressurized and one unpressurised HSSP tested under monotonic displacement-controlled bending. Isotropic and anisotropic material modeling methods are used for each HSSP models. In the isotropic material model, longitudinal stress-Strain data of HSSP material is used to define the stress-Strain relationship. In the anisotropic model combined hardening material model, calibrated by longitudinal and transverse HSSP stress-Strain data, is used. Critical Buckling Strain predictions by isotropic and anisotropic models of these pipes are compared with test results and also with some available criteria in standards and literatures. These comparisons show that anisotropic models give predictions closer to test results.Copyright © 2010 by ASME

Weiqiu Chen - One of the best experts on this subject based on the ideXlab platform.

  • Buckling of a stiff thin film on a bi-layer compliant substrate of finite thickness
    International Journal of Solids and Structures, 2020
    Co-Authors: Chengjun Wang, Zhang Shun, Shuang Nie, Weiqiu Chen, Jizhou Song
    Abstract:

    Abstract The Buckling of a stiff thin film on a compliant substrate has been widely studied over the past decade due to its wide applications such as stretchable electronics, micro- and nano-metrology, and surface engineering. Instead of a single-layer compliant substrate, a bi-layer compliant substrate is usually encountered in practical applications. In this paper, the Buckling of a stiff thin film on a bi-layer compliant substrate of finite thickness is studied theoretically, numerically and experimentally. The theoretical models based on the small-deformation theory and the simple finite-deformation theory accounting for the geometry change by using the energy method are both developed and presented. The good agreement among theoretical predictions, finite element analysis and experimental measurements of the Buckling behavior validates the theoretical model. The influences of finite thickness of the bi-layer substrate and substrate modulus ratio on the Buckling wavelength and Critical Buckling Strain are systematically investigated. The Buckling configurations at various applied Strains are also measured to further validate the theoretical model. These results shed light on the influence of finite substrate thickness on Buckling of the bi-layer substrate-supported thin films and are helpful to provide design guidelines in practical applications.

  • Buckling of a stiff thin film on an elastic graded compliant substrate
    Proceedings of The Royal Society A: Mathematical Physical and Engineering Sciences, 2017
    Co-Authors: Zhou Chen, Weiqiu Chen, Jizhou Song
    Abstract:

    The Buckling of a stiff film on a compliant substrate has attracted much attention due to its wide applications such as thin-film metrology, surface patterning and stretchable electronics. An analytical model is established for the Buckling of a stiff thin film on a semi-infinite elastic graded compliant substrate subjected to in-plane compression. The Critical compressive Strain and Buckling wavelength for the sinusoidal mode are obtained analytically for the case with the substrate modulus decaying exponentially. The rigorous finite element analysis (FEA) is performed to validate the analytical model and investigate the postBuckling behaviour of the system. The Critical Buckling Strain for the period-doubling mode is obtained numerically. The influences of various material parameters on the results are investigated. These results are helpful to provide physical insights on the Buckling of elastic graded substrate-supported thin film.