Woven Fabric Composite Materials Research Articles

Optimization of Uniaxial Tensile Stress-Strain Response of 3D Angle Interlock Woven Fabric Composite using Weft Density and Draw-In Plan Variables

Currently, 2D woven composites are extensively incorporated into a variety of technical automotive body parts and protective body armor owing to their excellent fabric strength performance. However, there is still a lack of attempts to utilize 3D woven fabrics for the same technical application. Hence, it is vital to examine the fundamental tensile strength of woven fabric composite materials when determining their suitability for end-use applications. This study aimed to investigate the novel effects of two parameters on the uniaxial tensile strength of a high-tenacity polyester three-layer 3D angle interlock (3DAI) woven fabric composite, namely, weave drafting draw-in insertion and weave density. Four different drafting patterns were considered: pointed (DRW 1), broken (DRW 2), broken mirror (DRW 3), and straight (DRW 4), for weft density at 14 and 25 pick.cm-1. Samples of the 3DAI woven fabric reinforced with epoxy composite at different drafting patterns and weft density combinations were produced and tested. Consequently, the maximum tensile stress and strain were recorded in the woven fabric composite sample with DRW 4 and 25 pick.cm-1 at 113 MPa and 11%, respectively. The study shows that different weft densities and draw-in plan settings play a significant role in the tensile strength performance of the 3DAI woven composite.

Fractographic analysis of scarf repaired carbon/epoxy laminates submitted to tensile strength

This study presents the main fractographic aspects and failure modes involved on the fracture of scarf repaired laminates submitted to tensile test, using scanning electron microscopy (SEM) technique. A detailed analysis of the fractographic aspects was carried out correlating them to the failure modes, the local crack propagation, and the mechanical performance of the scarf joint. SEM analyses showed cohesive failure of the adhesive film associated with a strong mechanical anchoring between the adhesive and the laminate, as well as a good patch ply consolidation on the adhesive interface, showing the joining mechanism efficiency. Fiber pull-out mechanism associated with the translaminar fracture, combined with intralaminar fracture were the predominant failure modes observed in the parent laminate and in the patch repaired region, evidencing the complexity on crack growing in woven fabric composite materials. Fractographic analyses provide evidences that justify the good mechanical behavior of the repaired laminates that is attributed to high interfacial shear strength of the scarf joint and overall good quality of the repair manufacturing process.

Analysis for thermal deformation of cylindrical structural member made of woven fabric composite material

Analysis for thermal deformation of cylindrical structural member made of woven fabric composite material

Contribution for a better characterization of the tensile mechanical behaviour of flax/PP biocomposite materials

This work aims to characterize the mechanical behaviour in tension of biocomposite (polypropylene/flax fibres), using a digital image correlation device The preliminary results show that the strain level at the surface of the tested specimen is not uniform. It also appears that the position of the observation area greatly affects the measured strain level. This is attributed to both the inhomogeneity in the internal structure in the woven fabric composite materials and the change in the local damage process from one area to another within the loaded specimen, as confirmed by the microscopic observations of fracture facies of broken specimens. To overcome these drawbacks, the observation area is enlarged to the entire surface of the loaded specimen. In this case, the results clearly indicate that the tensile stress strain curves of the woven flax/PP specimen loaded in wrap and weft directions show a bi-linearity mechanical behaviour, characterized, as generally reported in the literature, with a knee point at 20 MPa in stress and 0.2% in strain. In the shear plan direction, however, a nonlinear behaviour is obtained. Finally, based on the SEM observations, the dominating damage mechanisms in tension of this composite (kink bands, splitting cracks at flax bundles, fiber failure, and matrix cracks) are identified.

Viscoelastic modelling and dynamic characteristics of CNTs-CFRP-2DWF composite shell structures

Abstract The carbon nanotubes (CNTs) are well known for its application in the areas of advanced composite materials for their improved elastic properties. The large specific interfacial surface area owing to tiny dimensions of CNTs may greatly escalation the interfacial sliding which may promote the dissipation of energy in a dynamic situation that makes them very ideal for damping applications in engineering structures/systems. The present article investigates the viscoelastic modelling and dynamic responses of the CNTs – based carbon fiber reinforced two dimensional woven fabrics (CNTs-CFRP-2DWF) composite spherical shell panels where CNTs are reinforced in the polymer matrix phase. The Mori – Tanaka (MT) micromechanics in conjunction with weak interface (WI) theory has been developed for the mathematical formulations of the viscoelastic modelling of CNTs-based polymer matrix phase. Further, strength of material (SOM) method has been employed to formulate viscoelastic material behavior of the yarn and finally the viscoelastic properties of the representative unit cell (RUC) is established based on the unit cell method (UCM). An eight-node shell element with five degree of freedom per node has been formulated to study the vibration damping characteristics of spherical shell structures made by CNTs-CFRP-2DWF composite materials. The shell finite element formulation is based on the transverse shear effect as per the Mindlin's hypothesis, and stress resultant-type Koiter's shell theory. Frequency and temperature dependent material properties of such CNTs-CFRP-2DWF composite materials have been obtained and analysed. Impulse and frequency responses of such structures have been performed to study the effects of various important parameters such as volume fraction of CNTs, interfacial condition, agglomeration, temperature, geometries of shell panel on the material properties and such dynamic responses. Obtained results demonstrate that quick vibration mitigation may be possible using such CNTs-CFRP-2DWF composite material which is desirable to overcome the drawbacks of conventional CFRP woven fabric composite materials.

Modeling and analyses of thermo-elastic properties of radially grown carbon nanotubes-based woven fabric hybrid composite materials

ABSTRACTCarbon nanotubes (CNTs) may be useful due to their sound thermo-mechanical properties. The present work deals with the evaluation and analysis of elastic properties and coefficient of thermal expansions (CTEs) of a CNTs-based 2D plane woven fabric composite material system where the CNTs are radially grown on the surface of the carbon fiber. Detailed constructional features of the proposed trans-scale composite material system is explained in detail. The mathematical modeling for the material properties of each constituent or building block of the hybrid composite is developed. The mathematical model for the thermo-elastic properties of yarns is also formulated based on strength of material method whereas the thermo-elastic properties of representative unit cell is based on the unit cell method. Various numerical results have been obtained by varying the CNTs content, carbon fiber contents, and temperatures. Effects of different geometrical parameters (such as yarn thickness, yarn width, and the ratio of gap length to yarn width of the yarn) on the elastic properties as well as the CTEs are also investigated.

On the fabrication of carbon fabric reinforced epoxy composite shell without joints and wrinkling

This article describes a simple and cost effective fabrication procedure by using hand lay-up technique that is employed for the manufacturing of thin-walled axi-symmetric composite shell structures with carbon, glass and hybrid woven fabric composite materials. The hand lay-up technique is very commonly used in aerospace and marine industries for making the complicated shell structures. A generic fabrication procedure is presented in this paper aimed at manufacture of plain Carbon Fabric Reinforced Plastic (CFRP) and Glass Fabric Reinforced Plastic (GFRP) shells using hand lay-up process. This paper delivers a technical breakthrough in fabrication of composite shell structures without any joints and wrinkling. The manufacture of stiffened CFRP shells, laminated CFRP shells and hybrid (carbon/glass/epoxy) composite shells which are valued by the aerospace industry for their high strength-to-weight ratio under axial loading have also been addressed in this paper. A fabrication process document which describes the major processing steps of the composite shell manufacturing process has been presented in this paper. A study of microstructure of the glass fabric/epoxy composite, carbon fabric/epoxy composite and hybrid carbon/glass/fabric epoxy composites using Scanning Electron Microscope (SEM) has been also carried out in this paper.

Static mechanical properties of GFRP laminates with fly ash and graphite as filler material

Glass fiber reinforced polymer matrix (GFRP) woven fabric composite material was tested to determine tensile, Flexural and Impact strength. In this paper a comparison study is done for Tensile, Flexural and Impact strength taking two different materials such as (i) woven glass fibre Aralide LY 556epoxy matrix laminates and (ii) woven glass fibre Vinyl Ester epoxy matrix laminates. 1% Graphite and 1% Ash clay are used as filler material as the use of fillers in the matrix, gives rise to many combinations that provide increasing load withstanding capability, reduced coefficient of friction, improved wear resistance and improved thermal properties.

Thermo-mechanical properties of 5-harness satin fabric composites

The use of woven textile reinforcements in composite structures increased significantly in the past decades due to their interesting properties over unidirectional fibres. Therefore, the prediction of the thermo-mechanical properties of woven fabric composites is essential from a design and manufacturing standpoint. A micromechanical approach based on finite element method that utilizes three-dimensional unit cell was applied to predict the effective properties of a periodic woven fabric composite material. Using the resin processing properties models such as cure kinetics, shrinkage, glass transition temperature and elastic modulus models, the development of the periodic woven fabric composite material thermo-mechanical properties, as the cure progresses was predicted. The residual strains and stresses generated in the composite unit cell during the cure were also predicted and linked with the development of the material properties. The effective properties of the cured woven fabric composite material were compared to the one of an equivalent cross-ply composite material to verify the validity of neglecting the fibre waviness while modelling woven fabric composite.

Copper, stainless steel, glass core yarn, and ply yarn woven fabric composite materials properties

A study on physical and mechanical properties of copper core yarn, stainless core yarn, glass core yarn, and copper ply yarn woven fabric composite materials through ANOVA has been reported. Copper, stainless steel, and glass filaments are selected as the core, and cotton is selected as the sheath. The various combinations of copper, stainless, and glass core yarns are produced by DREF II Friction spinning machine, and core yarns are converted into woven fabric composite materials by loom. The physical and mechanical properties of copper core yarn, stainless core yarn, glass core yarn, and copper ply yarn woven fabric composite materials have been measured using various instruments. It is observed that there is strong and significant difference between the tensile strength of warp direction and weft direction of core yarn woven fabric composite materials. The flexural rigidity and bending modulus of core yarn fabric increases with an increase in core content of copper, stainless steel, and glass filament.

복합재료의 기계적 거동에 염수환경이 미치는 영향에 관한 연구

본 연구에서는 염수 침수 실험과 염수 분무 실험이라는 두 가지의 실험을 위그선의 구조재료로 사용될 3가지 다른 복합재료 시스템에 대해서 해수와의 접촉에 의한 물성저하를재현하기 위해 수행하였다. 140일간 염수환경하에서 노화시킨 후 탄소섬유 복합재료와유리섬유 복합재료의 인장, 압축, 전단 강성과 강도 및 층간 전단 강도를 측정하였다. 기본 물성파의 비교를 통해서 염수환경이 복합재료의 기계적 물성에 미치는 영향이 평가되었다. 실험을 통해 염수 분무환경과 침수 환경의 차이는 거의 영향을 미치지 않음을 확인하였다. 탄소섬유 복합재료의 경우 인장 물성에 적은 손실이 발생한 반면 유리섬유 복합재료에서는 인장물성의 저하률이 탄소섬유 복합재료에 비해서 큼을 확인하였다. 그리고 모재 지배적 물성들의 큰 물성저하가 관찰되었다. 이를 통해, 염수는 복합재료의 섬유와 모재 사이의 계면을 퇴화시키고, 또한 모재 자체 물성과 유리섬유의 물성을 저하시킬 수 있음을 확인하였다. In this paper, two different experiments, namely, salt water spray and salt water immersion, were performed to reproduce the contact of composites with the seawater for three kinds of woven fabric composite material systems which would be used for the WIG(wing in ground effect)craft. After aging 140 days in the salt water environment, material properties of carbon/epoxy and glass/epoxy composite such as tensile, compressive and shear stiffness and strength, and inter-laminar shear strength (ILSS) were measured. By comparing baseline material properties with degraded ones, the effects of the salt water environment on the composite mechanical properties were evaluated. From the experiments, it was confirmed that the difference in aging conditions had very small influence on composite properties. And it was found that tensile strength of carbon/epoxy composites showed little degradation, but much more degradation was observed in glass/epoxy composites. And large degradations on matrix dominant properties were observed. The salt water could damage the fiber-matrix interface, matrix properties and the glass fiber.

Application of Mesh Free Method to Evaluation of Woven Fabric Composite Elastic Moduli

A computational method for the micro-mechanical material model of woven fabric composite material was developed in this paper based on a repeated unit cell approach and two smooth fibre modes were presented. The stiffness matrix was evaluated with a domain integral by the use of radial basis function interpolations without element mesh. The applications of mesh free method to evaluate woven fabric composite elastic moduli have been presented and good accuracy has been achieved compared with the results by other approaches.

The Simulation of Dual Layer Fuel Tank During the Impact With the Ground Based on Parallel Computing

The crashworthiness of a dual layer fuel tank, with the outer layer made of metal and the inner layer made of woven fabric composite material, is fundamental for the survivability of an impact with the ground in emergency. In this research, the simulation of a three-dimensional dual layer fuel tank in the impact with the ground is achieved through the multimaterial arbitrary Lagrangian-Eulerian (ALE) finite element method because of its ability to control mesh geometry independently of geometry. At the same time, the naked flexible tank in the impact with the ground is simulated for the evaluation of the outer metal tank. The ALE description is adopted for the fluid domain, while for the structural domain the Lagrangian formulation is considered. The computation of the fluid-structure interaction and the impact contact between the tank and the ground are realized by the penalty-based coupling method. Then, the dynamic behaviors of the dual layer fuel tank and the naked flexible tank in the impact are analyzed. In the meantime, the parallelism of the dual layer fuel tank is discussed because the computation of the fluid-structure interaction and the impact contact is quite time consuming. Based on domain decomposition, the recursive coordinate bisection (RCB) is improved according to the time-consuming characteristics of fluid-filled tank in the impact. The result indicates, comparing with the RCB algorithm, that the improved recursive coordinate bisection algorithm has improved the speedup and parallel efficiency.

Moisture Effect on the Interlaminar Resistance of Woven Fabric Thermoplastic Composite

In the present study, the effect of moisture on the interlaminar fracture toughness of two woven fabric composite materials has been investigated. The composites used are made of a woven fabric 8H Satin glass fiber and 8H Satin carbon fiber. The matrix is a polyetherimide (PEI). The composites are used in aeronautical and aerospace applications. The interlaminar fracture behavior is analyzed using the mode I, double cantilever beam (DCB) test, and the mode II, end notched flexure (ENF), in order to determine the energy required for the initiation and growth of an artificial crack. The composites are subjected to a relative humidity (95%) and a constant temperature (70° C) in a climatic chamber for 30, 60, 120, and 180 days. The delamination energies are calculated using the corrected beam, Berry theories, and the experimental calibration method at the characteristic points. The result shows that the decrease in the fracture behavior is more important in the material CD342 8H Satin weave. The fracture mechanism was also analyzed by means of scanning electron microscopy.

Progressive failure modeling of woven fabric composite materials using multicontinuum theory

Failure of composite materials often results from damage accumulation in the individual constituents (fiber and matrix) of the composite. At times, damage may even be limited to a single constituent. The ability to accurately predict not only ultimate strength values but also intermediate constituent level failures is crucial to the success of introducing composite materials into demanding structural applications. In this paper, we develop two progressive failure models for the analysis of a plain weave composite material. The formulations are based on treating the weave as consisting of separate but linked continua representing the warp fiber bundles, fill fiber bundles, and pure matrix pockets. Retaining constituent identities allows one to access constituent (phase averaged) stress fields that are used in conjunction with both a stress based and damage based failure criterion to construct a nonlinear progressive failure algorithm for the woven fabric composite material. The MCT decomposition and the nonlinear progressive failure algorithm are incorporated within the framework of a traditional finite element analysis. The constituent based progressive failure algorithm combined with both the stress based and damage based failure criteria are compared against experimental data for a plain weave, woven fabric composite under various loading conditions. The analytical results from the damage based approach show a marked improvement over the stress based predictions and are in excellent agreement with the experimental data.

Estimation Method of Damping Properties for Woven Fabric Composites

An estimation method of damping properties for woven fabric composite materials has been proposed. To obtain the material damping of woven fabric composites, the maximum strain energy and kinetic strain energy are calculated by finite element method based on the strain energy method. The proposed method has been applied to plain woven fabric composites plates and compared with experimental results to evaluate the validity of the method. It is recognized that the computational results have agreed well with the experimental ones. Next, the effect of the angle of fiber bundles on material damping properties of plain woven fabric composites has been investigated by proposed method. From these points of view, the proposed simulation method is very useful for the estimation of material damping properties.

1744 三次元織構造の有限要素モデリングと織物複合材料の力学的特性評価システムの構築(S16-4 複合材料(2),S16 先進材料の強度・機能評価とメゾメカニックス)

As woven fabric composite materials have the excellent impact resistance and ductility, it is used for many industrial and aerospace fields. However, it is very difficult to evaluate the mechanical behavior because of the complicated geometrical architecture. We have proposed the evaluation system for the mechanical behaviors by FEM with the finite element mesh generation of the microstructure. In this paper, a finite element mesh generator based on the fiber bundle data obtained by WiseTex and a simulation system for the mechanical behaviors of woven composites have been described. As an example, the mechanical behavior of H Shape structure with 3D woven composites is carried out. It is revealed that the mechanical characterization of textile composites can be evaluated by the proposed system.

Micromechanics of fabric reinforced composites with periodic microstructure

A model to predict the effective stiffness of woven fabric composite materials is presented. Taking advantage of the inherent periodicity of woven fabric architecture, periodic microstructure theory is used at the mesoscale for the case of a two-phase heterogeneous material with multiple periodic inclusions. For plain weave fabrics, the representative volume element (RVE) is discretized into fiber/matrix bundles and the pure matrix regions that surround them. The surfaces of the fiber/matrix bundles are fit with sinusoidal equations using two approaches. The first is based on measurements taken from photomicrographs of composite specimens and the second is based on an idealized representation of the plain weave structure. Three-dimensional sinusoidal surfaces are generated from the face equations and weave shape for the real and idealized cases in order to mathematically describe the fiber/matrix bundle regions, which are treated as unidirectional composites. Model results from the idealized geometry are compared to experimental data from the literature and show good agreement, including interlaminar material properties. From a comparison of the real and idealized geometry results for similar material RVE dimensions, it is seen that the model is capable of predicting significant changes in the in-plane material properties from slight mismatch in the fiber/matrix bundle shape and crimp, which can be captured using the geometric surfaces generated from photomicrograph measurements.

損傷力学に基づいた綾織強化複合材料の3次元有限要素解析(S07-3 複合材料I,S07 メゾスケールにおける先進材料の力学と強度・機能評価)

損傷力学に基づいた綾織強化複合材料の3次元有限要素解析(S07-3 複合材料I,S07 メゾスケールにおける先進材料の力学と強度・機能評価)

124 織物複合材料構造物の減衰予測(減衰の評価と予想手法,OS-11:ダンピング(1))

The estimation method of the damping properties for woven fabric composite materials has proposed. The proposed method has been applied to the plain woven fabric composites. Experiments have been conducted to evaluate the validity of the proposed method. It is recognized that the computational results have agreed with the experimental ones. -Next, it has evaluated the effect of angle of fiber bundle on material damping of plain woven fabric composites. The results show that the damping ratio is highest at angle of 45 degree.