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

  • moisture absorption characteristics and mechanical degradation of Composite lattice truss core Sandwich Panel in a hygrothermal environment
    Composites Part A-applied Science and Manufacturing, 2019
    Co-Authors: Jie Mei, Jiayi Liu, P J Tan, Wei Huang
    Abstract:

    Abstract This paper investigates the impact of hygrothermal aging upon the compressive mechanical properties of carbon fiber reinforced plastics (CFRP) Composite Sandwich Panels with a tetrahedral truss core. Gravimetric absorption data, through accelerated moisture absorption tests, were presented for three different temperatures of 30 °C, 55 °C and 80 °C. Predictions by Fickian and Langmuir-type diffusion models were compared to evaluate which one best describe the moisture diffusion process in the Sandwich Panels. A subroutine implementing the Langmuir-type diffusion model in ABAQUS was developed to simulate the variations of moisture concentration. The compressive properties of Composite strut and tetrahedral truss cores Sandwich Panel after hygrothermal aging at different temperatures were tested, respectively. The experimental results indicated that the degradation of compressive properties of Composite Sandwich Panel was induced by the combined effect of temperature and moisture absorption. Analytical expressions were developed to predict the compressive strength and stiffness of the Sandwich Panel following hygrothermal aging. A good agreement was found between the predictions by finite element, analytical model and experimental results.

  • bending response and failure mechanism of Composite Sandwich Panel with y frame core
    Thin-walled Structures, 2019
    Co-Authors: Jialin Liu, Jiayi Liu, Wei Huang
    Abstract:

    Abstract The hot-press molding technique was developed to fabricate the Y-frame Sandwich core from carbon fiber reinforced polymer Composite. The three-point bending tests were conducted to investigate mechanical behavior of the Y-frame Sandwich core. The effects of the relative density on the mechanical behavior of the Y-frame Sandwich core were revealed by the experiments. The bending load-displacement curves were recorded, which indicated that the bending properties of the Y-frame Sandwich core were strongly influenced by the relative density. The bending failure load and the value of P / δ were analytically predicted. The discrepancy between the experimental results and the predictions was analyzed. Furthermore, the analytical prediction also revealed that the value of P / δ was dependent on the span length of the Composite Y-frame Sandwich core.

  • Temperature effects on the compressive properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores
    Composites Part A: Applied Science and Manufacturing, 2018
    Co-Authors: Junmeng Zhou, Jie Mei, Jiayi Liu, Jialin Liu, Yu Wang, Wei Huang, Yuling Tang
    Abstract:

    Abstract The effects of temperature on the mechanical properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores under out-of-plane compression have been studied in this paper. The carbon fiber Composite Sandwich Panel with Y-shaped cores was manufactured by a hot-press method using unidirectional carbon/epoxy prepregs. The out-of-plane compression tests of Composite Sandwich Panels were conducted at temperatures ranging from 20 °C to 200 °C. Then the stress-strain curves, failure modes, compressive stiffness and strength of Composite Sandwich Panel at high temperatures were analyzed and compared with those ones at room temperature. The results have shown that temperature had a significant effect on mechanical properties and failure behaviors of Composite Sandwich Panel. And high temperature resulted in the decreasing of compressive stiffness and strength. Finally, the analytical expressions were presented to predict the compressive stiffness and strength of Composite Sandwich Panel and compared with experimental results at different temperatures.

  • Temperature effects on the compressive properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores Part A Applied science and manufacturing
    Composites, 2018
    Co-Authors: Junmeng Zhou, Jie Mei, Jiayi Liu, Jialin Liu, Yu Wang, Wei Huang, Yuling Tang
    Abstract:

    The effects of temperature on the mechanical properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores under out-of-plane compression have been studied in this paper. The carbon fiber Composite Sandwich Panel with Y-shaped cores was manufactured by a hot-press method using unidirectional carbon/epoxy prepregs. The out-of-plane compression tests of Composite Sandwich Panels were conducted at temperatures ranging from 20 °C to 200 °C. Then the stress-strain curves, failure modes, compressive stiffness and strength of Composite Sandwich Panel at high temperatures were analyzed and compared with those ones at room temperature. The results have shown that temperature had a significant effect on mechanical properties and failure behaviors of Composite Sandwich Panel. And high temperature resulted in the decreasing of compressive stiffness and strength. Finally, the analytical expressions were presented to predict the compressive stiffness and strength of Composite Sandwich Panel and compared with experimental results at different temperatures.

  • a novel fabrication method and mechanical behavior of all Composite tetrahedral truss core Sandwich Panel
    Composites Part A-applied Science and Manufacturing, 2017
    Co-Authors: Jie Mei, Jiayi Liu, Jialin Liu
    Abstract:

    Abstract A novel hot-press molding method was developed to manufacture all-Composite Sandwich Panel with tetrahedral truss cores in this paper. The out-of-plane compressive and in-plane shear behaviors of this structure were investigated by experiments. The results have shown that the tetrahedral truss core Sandwich Panel had a high compressive specific strength compared to metallic truss core Sandwich Panels. The node failure was observed in the experimental process. Finite element analysis (FEA) with a progressive failure model was involved to simulate the damage evolution process and predict the mechanical properties. The analytical formulae were also presented to predict the stiffness and strength of Sandwich Panel. Good agreement was found between FEA calculated results and the experimental results. It is expected that this study can provide useful information for the fabrication and application of all-Composite tetrahedral truss core Sandwich Panel.

Zhen-gong Zhou - One of the best experts on this subject based on the ideXlab platform.

  • The compressive responses of glass fiber Composite pyramidal truss cores Sandwich Panel at different temperatures
    Composites Part A: Applied Science and Manufacturing, 2015
    Co-Authors: Jiayi Liu, Wufeng Qiao, Jingxi Liu, De Xie, Zhen-gong Zhou
    Abstract:

    Abstract A new method for fabricating glass fiber Composite Sandwich Panel with pyramidal truss cores was developed based on the vacuum assisted resin transfer molding technology. The microstructure and organizations of fabricated Sandwich Panels were examined by the scanning electron microscope. The out-of-plane compressive tests of Composite Sandwich Panels were performed throughout the temperature range from −60 °C to 125 °C. Then the effects of temperature on the compressive strength, compressive modulus and failure mechanism were investigated and analyzed. Our results indicated that cryogenic temperature resulted in the increasing of the compressive modulus and strength, while high temperature caused the degradation of the compressive modulus and strength. The effect of temperature on failure mode of Composite Sandwich Panel was also observed. Analytical expressions were presented to predict the compressive modulus and strength of Composite Sandwich Panels at different temperatures.

  • effects of thermal exposure on mechanical behavior of carbon fiber Composite pyramidal truss core Sandwich Panel
    Composites Part B-engineering, 2014
    Co-Authors: Jiayi Liu, Xiang Zhu, Zhen-gong Zhou
    Abstract:

    Abstract An experimental study was performed to investigate the effect of high temperature exposure on mechanical properties of carbon fiber Composite Sandwich Panel with pyramidal truss core. For this purpose, Sandwich Panels were exposed to different temperatures for different times. Then Sandwich Panels were tested under out-of-plane compression till failure after thermal exposure. Our results indicated that both the thermal exposure temperature and time were the important factors affecting the failure of Sandwich Panels. Severe reductions in residual compressive modulus and strength were observed when Sandwich Panels were exposed to 300 °C for 6 h. The effect of high temperature exposure on failure mode of Sandwich Panel was revealed as well. Delamination and low fiber to matrix adhesion caused by the degradation of the matrix properties were found for the specimens exposed to 300 °C. The modulus and strength of Sandwich Panels at different thermal exposure temperatures and times were predicted with proposed method and compared with measured results. Experimental results showed that the predicted values were close to experimental values.

  • mechanical behavior and failure mechanisms of carbon fiber Composite pyramidal core Sandwich Panel after thermal exposure
    Journal of Materials Science & Technology, 2013
    Co-Authors: Jiayi Liu, Zhen-gong Zhou
    Abstract:

    An attempt has been made here to evaluate the effect of thermal exposure on the mechanical behavior and failure mechanisms of carbon fiber Composite Sandwich Panel with pyramidal truss core under axial compression. Analytical formulae for the collapse strength of Composite Sandwich Panel after thermal exposure were derived. Axial compression tests of Composite laminates and Sandwich Panels after thermal exposure were conducted at room temperature to assess the degradation caused by the thermal exposure. Experimental results showed that the failure of Sandwich Panel are not only temperature dependent, but are time dependent as well. The decrease in residual compressive strength is mainly attributed to the degradation of the matrix and the degradation of fiber–matrix interface, as well as the formation of cracks and pores when specimens are exposed to high temperature. The measured failure loads obtained in the experiments showed reasonable agreement with the analytical predictions.

  • A study on mechanical behavior of the carbon fiber Composite Sandwich Panel with pyramidal truss cores at different temperatures
    Science China-physics Mechanics & Astronomy, 2012
    Co-Authors: Zhen-gong Zhou, Linzhi Wu, Li Ma
    Abstract:

    A series of compression tests were conducted to investigate the mechanical properties and failure mechanisms of carbon fiber Composite Sandwich Panels using pyramidal truss cores subjected to temperatures ranging from −100°C to 350°C. The compressive strength and stiffness of Sandwich Panels decreased as temperature increased. Cryogenic temperatures caused an increase in strength and stiffness, while elevated temperatures resulted in a reduction of strength and stiffness. The effect of temperature on the failure mode of the Sandwich Panel was revealed as well. The interface between the fiber and matrix was examined by a scanning electron microscope (SEM) in order to study the effect of temperature on strengthening the mechanism and good bonding conditions within the fiber-matrix interface was observed at cryogenic temperatures. The comparison of the predicted and experimental data indicated that the stiffness and strength of the Composite Sandwich Panels for temperature variation was consistent.

  • High Temperature Residual Properties of Carbon Fiber Composite Sandwich Panel with Pyramidal Truss Cores
    Applied Composite Materials, 2012
    Co-Authors: Jiayi Liu, Zhen-gong Zhou, Shidong Pan
    Abstract:

    A study on the mechanical property degradation of carbon fiber Composite Sandwich Panel with pyramidal truss cores by high temperature exposure is performed. Analytical formulae for the residual bending strength of Composite Sandwich Panel after thermal exposure are presented for possible competing failure modes. The Composite Sandwich Panels were fabricated from unidirectional carbon/epoxy prepreg, and were exposed to different temperatures for different time. The bending properties of the exposed specimens were measured by three-point bending tests. Then the effect of high temperature exposure on the bending properties and damage mechanism were analyzed. The results have shown that the residual bending strength of Composite Sandwich Panels decreased with increasing exposure temperature and time, which was caused by the degradation of the matrix property and fiber-matrix interface property at high temperature. The effect of thermal exposure on failure mode of Composite Sandwich Panel was observed as well. The measured failure loads showed good agreement with the analytical predictions. It is expected that this study can provide useful information on the design and application of carbon fiber Composite Sandwich Panel at high temperature.

Dushyanth Sirivolu - One of the best experts on this subject based on the ideXlab platform.

  • Foam-core, curved Composite Sandwich Panels under blast
    Journal of Sandwich Structures & Materials, 2013
    Co-Authors: Michelle S. Hoo Fatt, Yifei Gao, Dushyanth Sirivolu
    Abstract:

    An elastic-plastic model was developed for predicting the blast response of a foam-core, curved Composite Sandwich Panel. A multi-layered approach was used to distinguish facesheets and core deform...

  • a wave propagation model for the high velocity impact response of a Composite Sandwich Panel
    International Journal of Impact Engineering, 2010
    Co-Authors: M. S. Hoo Fatt, Dushyanth Sirivolu
    Abstract:

    A solution methodology to predict the residual velocity of a hemispherical-nose cylindrical projectile impacting a Composite Sandwich Panel at high velocity is presented. The term high velocity impact is used to describe impact scenarios where the projectile perforates the Panel and exits with a residual velocity. The solution is derived from a wave propagation model involving deformation and failure of facesheets, through-thickness propagation of shock waves in the core, and through-thickness core shear failure. Equations of motion for the projectile and effective masses of the facesheets and core as the shock waves travel through Sandwich Panel are derived using Lagrangian mechanics. The analytical approach is mechanistic involving no detail account of progressive damage due to delamination and debonding but changes in the load-bearing resistance of the Sandwich Panel due to failure and complete loss of resistance from the facesheets and core during projectile penetration. The predicted transient deflection and velocity of the projectile and Sandwich Panel compared fairly well with results from finite element analysis. Analytical predictions of the projectile residual velocities were also found to be in good agreement with experimental data.

  • a wave propagation model for the high velocity impact response of a Composite Sandwich Panel
    International Journal of Impact Engineering, 2010
    Co-Authors: M. S. Hoo Fatt, Dushyanth Sirivolu
    Abstract:

    A solution methodology to predict the residual velocity of a hemispherical-nose cylindrical projectile impacting a Composite Sandwich Panel at high velocity is presented. The term high velocity impact is used to describe impact scenarios where the projectile perforates the Panel and exits with a residual velocity. The solution is derived from a wave propagation model involving deformation and failure of facesheets, through-thickness propagation of shock waves in the core, and through-thickness core shear failure. Equations of motion for the projectile and effective masses of the facesheets and core as the shock waves travel through Sandwich Panel are derived using Lagrangian mechanics. The analytical approach is mechanistic involving no detail account of progressive damage due to delamination and debonding but changes in the load-bearing resistance of the Sandwich Panel due to failure and complete loss of resistance from the facesheets and core during projectile penetration. The predicted transient deflection and velocity of the projectile and Sandwich Panel compared fairly well with results from finite element analysis. Analytical predictions of the projectile residual velocities were also found to be in good agreement with experimental data.

  • High Velocity Impact of a Composite Sandwich Panel
    Sustainability, 2008
    Co-Authors: M. S. Hoo Fatt, Dushyanth Sirivolu
    Abstract:

    This paper presents analytical solutions for the deformation response of a Composite Sandwich Panel subjected to high velocity impact by a rigid blunt, cylindrical projectile. The solution is derived from a 2-degrees-of-freedom model for the Sandwich Panel involving local indentation, core crushing, and global bending/shear deformations. An example is given for a Composite Sandwich Panel consisting of orthotropic E-glass vinyl ester facesheets and PVC H100 foam core and subjecting to the high velocity impact of a blunt cylindrical projectile. The analytical solution for the local indentation and global deflection under the projectile was found to be within 15% of finite element analysis results.

Evgeny V. Morozov - One of the best experts on this subject based on the ideXlab platform.

  • influence of shear keys orientation on the shear performance of Composite Sandwich Panel with pvc foam core numerical study
    Materials & Design, 2013
    Co-Authors: Ahmed Mostafa, Krishna Shankar, Evgeny V. Morozov
    Abstract:

    Abstract The present study explores the effect of introducing shear key inserts between the face sheet and the foam core of the Composite Sandwich structure on the shear performance. Parametric finite element (FE) investigation using ABAQUS software has been performed to evaluate the effect of the shear key orientation (bi-axial model) on the shear response and the failure mode of the Composite Sandwich Panel under in-plane shear load and comparing the results with the zero orientation shear key model (uni-axial). Polyvinylchloride (PVC) foam has been used as a core material which Sandwiched between two thin strong face sheets of glass fibre reinforced polymer (GFRP) to build a high performance Sandwich Panel. Chopped strand glass fibre (CS) impregnated with epoxy resin was used as shear key material. A comprehensive material testing program was first carried out on the constituent materials in order to characterise its elastic response under different types of load. Different orientations of the shear keys, namely ±15°,±30°,±45°,±60° and 90/0°, have been investigated. The FE results showed an improvement in the initial stiffness and ultimate stress of the Sandwich Panel as a result of introducing the shear keys. The FE model precisely captured the failure mode and demonstrated that the model with ±60° was the most sustainable model among the other bi-axial models. In comparison with the bi-axial model, uni-axial model offered a remarkable enhancement in the shear performance compared with the bi-axial model and accordingly selected for the future investigation.

  • In-plane shear behaviour of Composite Sandwich Panel incorporated with shear keys methodology at different orientations: finite element study
    Journal of Composite Materials, 2013
    Co-Authors: Ahmed Mostafa, Krishna Shankar, Evgeny V. Morozov
    Abstract:

    The effect of introducing semi-circular shear keys in at the skin-core interface of the Composite Sandwich Panels is illustrated numerically in the current study using ABAQUS software. Particularly...

  • effect of shear keys diameter on the shear performance of Composite Sandwich Panel with pvc and pu foam core fe study
    Composite Structures, 2013
    Co-Authors: Ahmed Mostafa, Krishna Shankar, Evgeny V. Morozov
    Abstract:

    Abstract The present paper addresses the most dominant failure mode of Composite Sandwich Panels with foam core, where the prevention and limitation of debonding failure between skin and core is highly important design issues. This paper presents a semi-circular shear keys inserting between the skin and the foam core to improve the shear performance and skin–core debonding resistance for Sandwich Panels with foam core. Polyvinylchloride (PVC) and polyurethane (PU) foam core are chosen for the current study and Sandwiched between glass fibre reinforced polymer (GFRP) skins, while the chopped strand (CS) glass fibre impregnated with epoxy resin is used for the shear key. A parametric investigation on the effect of the shear keys diameter on the in-plane shear performance has been performed numerically. In order that, a comprehensive experimental testing program was performed on the constituents to obtain the basic parameters used in the finite element (FE) model. The FE model of the ordinary Sandwich Panel was validated experimentally and proved its capability to represent the shear response of the Sandwich Panel. The suggested design was numerically investigated to select the most effective diameter for the shear key under in-plane shear load. For all investigated Sandwich model configurations the suggested shear keys were able to stop skin–core debonding and to redirect it to diagonal orientation with a significant improvement in the overall shear performance.

Jie Mei - One of the best experts on this subject based on the ideXlab platform.

  • moisture absorption characteristics and mechanical degradation of Composite lattice truss core Sandwich Panel in a hygrothermal environment
    Composites Part A-applied Science and Manufacturing, 2019
    Co-Authors: Jie Mei, Jiayi Liu, P J Tan, Wei Huang
    Abstract:

    Abstract This paper investigates the impact of hygrothermal aging upon the compressive mechanical properties of carbon fiber reinforced plastics (CFRP) Composite Sandwich Panels with a tetrahedral truss core. Gravimetric absorption data, through accelerated moisture absorption tests, were presented for three different temperatures of 30 °C, 55 °C and 80 °C. Predictions by Fickian and Langmuir-type diffusion models were compared to evaluate which one best describe the moisture diffusion process in the Sandwich Panels. A subroutine implementing the Langmuir-type diffusion model in ABAQUS was developed to simulate the variations of moisture concentration. The compressive properties of Composite strut and tetrahedral truss cores Sandwich Panel after hygrothermal aging at different temperatures were tested, respectively. The experimental results indicated that the degradation of compressive properties of Composite Sandwich Panel was induced by the combined effect of temperature and moisture absorption. Analytical expressions were developed to predict the compressive strength and stiffness of the Sandwich Panel following hygrothermal aging. A good agreement was found between the predictions by finite element, analytical model and experimental results.

  • Temperature effects on the compressive properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores Part A Applied science and manufacturing
    Composites, 2018
    Co-Authors: Junmeng Zhou, Jie Mei, Jiayi Liu, Jialin Liu, Yu Wang, Wei Huang, Yuling Tang
    Abstract:

    The effects of temperature on the mechanical properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores under out-of-plane compression have been studied in this paper. The carbon fiber Composite Sandwich Panel with Y-shaped cores was manufactured by a hot-press method using unidirectional carbon/epoxy prepregs. The out-of-plane compression tests of Composite Sandwich Panels were conducted at temperatures ranging from 20 °C to 200 °C. Then the stress-strain curves, failure modes, compressive stiffness and strength of Composite Sandwich Panel at high temperatures were analyzed and compared with those ones at room temperature. The results have shown that temperature had a significant effect on mechanical properties and failure behaviors of Composite Sandwich Panel. And high temperature resulted in the decreasing of compressive stiffness and strength. Finally, the analytical expressions were presented to predict the compressive stiffness and strength of Composite Sandwich Panel and compared with experimental results at different temperatures.

  • Temperature effects on the compressive properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores
    Composites Part A: Applied Science and Manufacturing, 2018
    Co-Authors: Junmeng Zhou, Jie Mei, Jiayi Liu, Jialin Liu, Yu Wang, Wei Huang, Yuling Tang
    Abstract:

    Abstract The effects of temperature on the mechanical properties and failure mechanisms of Composite Sandwich Panel with Y-shaped cores under out-of-plane compression have been studied in this paper. The carbon fiber Composite Sandwich Panel with Y-shaped cores was manufactured by a hot-press method using unidirectional carbon/epoxy prepregs. The out-of-plane compression tests of Composite Sandwich Panels were conducted at temperatures ranging from 20 °C to 200 °C. Then the stress-strain curves, failure modes, compressive stiffness and strength of Composite Sandwich Panel at high temperatures were analyzed and compared with those ones at room temperature. The results have shown that temperature had a significant effect on mechanical properties and failure behaviors of Composite Sandwich Panel. And high temperature resulted in the decreasing of compressive stiffness and strength. Finally, the analytical expressions were presented to predict the compressive stiffness and strength of Composite Sandwich Panel and compared with experimental results at different temperatures.

  • a novel fabrication method and mechanical behavior of all Composite tetrahedral truss core Sandwich Panel
    Composites Part A-applied Science and Manufacturing, 2017
    Co-Authors: Jie Mei, Jiayi Liu, Jialin Liu
    Abstract:

    Abstract A novel hot-press molding method was developed to manufacture all-Composite Sandwich Panel with tetrahedral truss cores in this paper. The out-of-plane compressive and in-plane shear behaviors of this structure were investigated by experiments. The results have shown that the tetrahedral truss core Sandwich Panel had a high compressive specific strength compared to metallic truss core Sandwich Panels. The node failure was observed in the experimental process. Finite element analysis (FEA) with a progressive failure model was involved to simulate the damage evolution process and predict the mechanical properties. The analytical formulae were also presented to predict the stiffness and strength of Sandwich Panel. Good agreement was found between FEA calculated results and the experimental results. It is expected that this study can provide useful information for the fabrication and application of all-Composite tetrahedral truss core Sandwich Panel.