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Qingping Sun - One of the best experts on this subject based on the ideXlab platform.

  • phase transition induced Interfacial Debonding in shape memory alloy fiber matrix system
    International Journal of Solids and Structures, 2015
    Co-Authors: Yin Chi, Qingping Sun
    Abstract:

    Abstract This paper investigates the phase transition induced Interfacial Debonding of an embedded superelastic NiTi shape memory alloy (SMA) fiber in an epoxy matrix. In situ Interfacial Debonding morphology and the stress–strain responses of the fiber are obtained for different fiber diameter and surface roughness. It is shown that, depending on these fiber parameters, a ductile or a brittle Debonding can occur. The ductile Debonding is caused by the phase transition of the fiber and took place together with the propagating necking front of the martensite domain. Compared with the tension of a free-standing fiber, the fiber–matrix bonding can lead to an increase in the front propagating force (plateau) of the fiber. By using Griffith’s energy balance approach, the crack surface energy is derived and the predictions of crack driving force agree well with the experimental data.

  • Phase transition induced Interfacial Debonding in shape memory alloy fiber–matrix system
    International Journal of Solids and Structures, 2015
    Co-Authors: Yin Chi, Qingping Sun
    Abstract:

    Abstract This paper investigates the phase transition induced Interfacial Debonding of an embedded superelastic NiTi shape memory alloy (SMA) fiber in an epoxy matrix. In situ Interfacial Debonding morphology and the stress–strain responses of the fiber are obtained for different fiber diameter and surface roughness. It is shown that, depending on these fiber parameters, a ductile or a brittle Debonding can occur. The ductile Debonding is caused by the phase transition of the fiber and took place together with the propagating necking front of the martensite domain. Compared with the tension of a free-standing fiber, the fiber–matrix bonding can lead to an increase in the front propagating force (plateau) of the fiber. By using Griffith’s energy balance approach, the crack surface energy is derived and the predictions of crack driving force agree well with the experimental data.

Yin Chi - One of the best experts on this subject based on the ideXlab platform.

  • phase transition induced Interfacial Debonding in shape memory alloy fiber matrix system
    International Journal of Solids and Structures, 2015
    Co-Authors: Yin Chi, Qingping Sun
    Abstract:

    Abstract This paper investigates the phase transition induced Interfacial Debonding of an embedded superelastic NiTi shape memory alloy (SMA) fiber in an epoxy matrix. In situ Interfacial Debonding morphology and the stress–strain responses of the fiber are obtained for different fiber diameter and surface roughness. It is shown that, depending on these fiber parameters, a ductile or a brittle Debonding can occur. The ductile Debonding is caused by the phase transition of the fiber and took place together with the propagating necking front of the martensite domain. Compared with the tension of a free-standing fiber, the fiber–matrix bonding can lead to an increase in the front propagating force (plateau) of the fiber. By using Griffith’s energy balance approach, the crack surface energy is derived and the predictions of crack driving force agree well with the experimental data.

  • Phase transition induced Interfacial Debonding in shape memory alloy fiber–matrix system
    International Journal of Solids and Structures, 2015
    Co-Authors: Yin Chi, Qingping Sun
    Abstract:

    Abstract This paper investigates the phase transition induced Interfacial Debonding of an embedded superelastic NiTi shape memory alloy (SMA) fiber in an epoxy matrix. In situ Interfacial Debonding morphology and the stress–strain responses of the fiber are obtained for different fiber diameter and surface roughness. It is shown that, depending on these fiber parameters, a ductile or a brittle Debonding can occur. The ductile Debonding is caused by the phase transition of the fiber and took place together with the propagating necking front of the martensite domain. Compared with the tension of a free-standing fiber, the fiber–matrix bonding can lead to an increase in the front propagating force (plateau) of the fiber. By using Griffith’s energy balance approach, the crack surface energy is derived and the predictions of crack driving force agree well with the experimental data.

Somnath Ghosh - One of the best experts on this subject based on the ideXlab platform.

  • modeling Interfacial Debonding and matrix cracking in fiber reinforced composites by the extended voronoi cell fem
    Finite Elements in Analysis and Design, 2007
    Co-Authors: Somnath Ghosh
    Abstract:

    This paper introduces an extended Voronoi cell finite element model (X-VCFEM) for modeling the initiation and propagation of Interfacial Debonding and matrix cracking in fiber reinforced composite materials. Bilinear and linear cohesive zone models are added for representing Interfacial Debonding and matrix crack propagation, respectively. A series of criteria based on cohesive zone models are proposed for assessing the direction of damage development, which includes the crack propagation in matrix and its deflection behavior at an interface. Comparisons of X-VCFEM simulations with reference results validate the effectiveness of this new model. The capability of predicting the development of microcracks in composites is of great importance to the design and evaluation of structure. Effect of stereographic features such as size and shape of heterogeneities on damage evolution is also discussed.

  • a continuum damage mechanics model for unidirectional composites undergoing Interfacial Debonding
    Mechanics of Materials, 2005
    Co-Authors: Prasanna Raghavan, Somnath Ghosh
    Abstract:

    Abstract A continuum damage mechanics (CDM) model is developed in this paper for fiber reinforced composites with Interfacial Debonding. The model is constructed from rigorous micromechanical analysis of the Representative Volume Element (RVE) using the Voronoi cell FEM (VCFEM) that is followed by homogenizing microscopic variables using asymptotic homogenization. The microstructural damage mode considered in this paper is fiber–matrix Interfacial Debonding that is simulated using cohesive zone models in VCFEM. Following a systematic consideration of various order damage tensors, an anisotropic CDM model using fourth order damage tensor with stiffness characterized as an internal variable, is found to perform most accurately for this class of materials. The comparison of this CDM results with those obtained by homogenization of micromechanical analysis show excellent agreement between the two. Hence the CDM model is deemed suitable for implementing in macroscopic finite element codes to represent damage evolution in composites with significant efficiency.

  • Analysis of Interfacial Debonding in Three-Dimensional Composite Microstructures
    Journal of Engineering Materials and Technology, 2005
    Co-Authors: Shriram Swaminathan, N.j. Pagano, Somnath Ghosh
    Abstract:

    This paper is aimed at analyzing stresses and fiber-matrix Interfacial Debonding in three-dimensional composite microstructures. It incorporates a 3D cohesive zone interface model based element to simulate Interfacial Debonding in the commercial code ABAQUS. The validated element is used to examine the potential Debonding response in the presence of fiber-fiber interactions. A two-fiber model with unidirectional fibers is constructed and the effect of relative fiber spacing and volume fraction on the stress distribution in the matrix is studied. In addition, the effect of fiber orientation and spacing on the nature of initiation and propagation of Interfacial Debonding is studied in a two-fiber model. These results are expected to be helpful in formulating future studies treating optimal fiber orientations and payoff in controlling fiber spacing and alignment.

  • Interfacial Debonding analysis in multiple fiber reinforced composites
    Mechanics of Materials, 2000
    Co-Authors: Somnath Ghosh, Yong Ling, Bhaskar S. Majumdar, Ran Kim
    Abstract:

    Decohesion at multiple fiber interfaces of elastic fiber reinforced composites is modeled by the Voronoi cell finite element model (VCFEM) in this paper. Interfacial Debonding is accommodated by cohesive zone models, in which normal and tangential springs tractions are expressed in terms of Interfacial separation. Model simulations are compared with results from experiments using cruciform specimens, of single and multiple fiber polymer-matrix composites. An inverse problem is solved to calibrate the cohesive zone parameters. Debonding at fiber-matrix interfaces is simulated for different architectures, volume fractions and boundary conditions, to understand the influence of microstructural morphology and boundary conditions on the decohesion process.

Chun-hway Hsueh - One of the best experts on this subject based on the ideXlab platform.

  • Interfacial Debonding versus fiber fracture in fiber-reinforced ceramic composites
    1998
    Co-Authors: Chun-hway Hsueh, P.f. Becher
    Abstract:

    Toughening of fiber-reinforced ceramic composites by fiber pullout relies on Debonding at the fiber/matrix interface prior to fiber fracture when composites are subjected to tensile loading. The criterion of Interfacial Debonding versus crack penetration has been analyzed for two semi-infinite elastic plates bonded at their interface. When a crack reaches the interface, the crack either deflects along the interface or penetrates into the next layer depending upon the ratio of the energy release rate for Debonding versus that for crack penetration. This criterion has been used extensively to predict Interfacial Debonding versus fiber fracture for a crack propagating in a fiber-reinforced ceramic composite. Two modifications were considered in the present study to address the Debonding/fracture problem. First, the authors derived the analysis for a strip of fiber, which had a finite width and was sandwiched between two semi-infinite plates of matrix. It was found that the criterion of Interfacial Debonding versus fiber fracture depended on the fiber width. Second, a bridging fiber behind the crack tip was considered where the crack tip initially circumvented the fiber. Subsequent to this, either the interface debonded or the fiber fractured. In this case, the authors have considered a bridging-fiber geometry to establish a new criterion.

  • Crack-wake Interfacial Debonding criteria for fiber-reinforced ceramic composites
    Acta Materialia, 1996
    Co-Authors: Chun-hway Hsueh
    Abstract:

    The condition for progressive Debonding with friction along the debonded interface is considered for the bridging fiber in the crack-wake of fiber-reinforced ceramic composites. The energy-based criterion is adopted in the present study to analyze the debond length, the crack-opening displacement, and the displacement of the composite due to Interfacial Debonding. The results are identical to the previous results obtained from a simple approach, in which Interfacial Debonding is assumed to occur when the mismatch in the axial strain between the fiber and the matrix reaches a critical value. Furthermore, the mismatch-strain criterion is found to bear the same physical meaning as the strength-based criterion.

  • Criteria For Progressive Interfacial Debonding With Friction In Fiber-Reinforced Ceramic Composites
    MRS Proceedings, 1995
    Co-Authors: Chun-hway Hsueh
    Abstract:

    Criteria for progressive Debonding at the fiber/matrix interface with friction along the debonded interface are considered for fiber-reinforced ceramic composites. The energy-based criterion is adopted to analyze the debond length, the crack-opening displacement, and the displacement of the composite due to Interfacial Debonding. The analytical solutions are identical to those obtained from the mismatch-strain criterion, in which Interfacial Debonding is assumed to occur when the mismatch in the axial strain between the fiber and the matrix reaches a critical value. Furthermore, the mismatch-strain criterion is found to bear the same physical meaning as the strength-based criterion.

  • Interfacial Debonding and fiber pull-out stresses of fiber-reinforced composites, X: with an elastic Interfacial coating
    Materials Science and Engineering: A, 1993
    Co-Authors: Chun-hway Hsueh
    Abstract:

    Abstract Pull-out of a fiber with an elastic Interfacial coating, which has been used to facilitate Interfacial Debonding for ceramic composites, from a matrix is considered. The effects of the Interfacial coating on the stress transfer, and the Interfacial shear stresses at both the fiber-coating and the coating-matrix interfaces are analyzed. The stress transfer by Interfacial stress depends on both the effectiveness of the stress transfer and the loading stress carried by the coating. This loading stress decreases with decreasing Young's modulus of the coating when a constant load is applied on the fiber-coating system. Hence, depending on the balance between the above two factors, a moderately soft coating is required to maximize the Interfacial shear which, in turn, promotes Interfacial Debonding. The effects of coating thickness on stress transfer are also addressed.

  • Interfacial Debonding and fiber pull-out stresses of fiber-reinforced composites Part VI. Interpretation of fiber pull-out curves
    Materials Science and Engineering: A, 1991
    Co-Authors: Chun-hway Hsueh
    Abstract:

    Abstract The stress-displacement relationship of the fiber during the fiber pull-out process in a fiber-reinforced composite ( i.e. the fiber pull-out curve) is considered. Understanding of both Interfacial Debonding and friction at the debonded interface is essential in interpreting the fiber pull-out curve. The behavior of Interfacial Debonding, which can be unstable, partially stable or stable, is characterized in the present study. The debonded interface can be either subjected to Coulomb friction, or free of friction which is contingent upon the comparison between the residual clamping stress and the Interfacial radial tension induced by Poisson's contraction of the axially tensile-loaded fiber. The important parameters controlling the characteristics of Interfacial Debonding and friction are studied, and various fiber pull-out curves are elucidated.

Zhenhan Yao - One of the best experts on this subject based on the ideXlab platform.

  • Modeling of Interfacial Debonding crack in particle reinforced composites using Voronoi cell finite element method
    Computational Mechanics, 2003
    Co-Authors: Ran Guo, Hui Ji Shi, Zhenhan Yao
    Abstract:

    In this paper, Voronoi cell finite element method (VCFEM), introduced by Ghosh and coworkers (1993), is applied to describe the matrix-inclusion Interfacial Debonding for particulate reinforced composites. In proposed VCFEM, the damage initiation is simulated by partly Debonding of the interface under the assumption of the critical normal stress law, and gradual matrix-inclusion separations are simulated with an interface remeshing method that a critical Interfacial node at the crack tip is replaced by a node pairs along the debonded matrix-inclusion interface and a more pair of nodes are needed to be added on the crack interface near the crack tip in order to better facilitate the free-traction boundary condition and the jumps of solution. The comparison of the results of proposed VCFEM and commercial finite element packages MARC and ABAQUS. Examples have been given for a single inclusion of gradually Interfacial Debonding and for a complex structure with 20 inclusions to describe the Interfacial damage under plane stress conditions. Good agreements are obtained between the VCFEM and the general finite element method. It appears that this method is a more efficient way to deal with the Interfacial damage of composite materials.