Effect Of Fiber Orientation Angle Research Articles

Investigation of patch application failure behaviors according to fiber orientation difference at notched composite plates

In this study, the damage behaviors of different type notched composite plates bonded with external composite patches were investigated experimentally under static tensile test. Eight-layer woven glass fiber reinforced epoxy resin matrix composite plates and epoxy based adhesive were used as materials. Notch type, fiber orientation angle, double side repair and single side repair were used as parameter. Effects of fiber orientation angle was investigated for 0 ° , 15 ° , 30 ° and 45 ° . Radial notch in the center (Type I), semicircular notch on the plate edge (Type II), a circular hole in the plate center (Type III) and U notch at the edges (Type IV) have been examined for 4 different notch types. The outstanding feature of this study is that many parameters were compared for many samples under the same experimental conditions. The composite plates and patches were used from same materials. Reducing of the damage loads has been observed for all notch types depending upon the increasing of fiber orientation angle significantly. In addition, that patch application to different fiber orientation plates is quite effective on damage loads. The extension was changed depending on the notch geometry at unrepaired composite. The load increasing rate is between + % 24 and + % 189 for one-sided bonded repair; + % 60 and + % 349 for two-sided bonded repair compared to the unrepaired samples. The results of this work can serve as a guide for workers to improve repair quality and durability in an understandable way.

Fundamental frequencies of composite rectangular plates with different cut-outs

This paper demonstrates the effects of various parameters on the fundamental frequency of a rectangular laminated composite plate with different shape of cutout (i.e. elliptical, rectangular and diamond shaped cutout). The shape and size of the cutout, fiber-orientation angle and boundary condition of the rectangular plate are considered parameters in the present study. Modal analysis was performed using finite element analysis to determine the fundamental frequency. The model has been validated using the published results. Fully clamped plate possesses the highest and cantilever plate possesses the lowest fundamental frequency. Plate with diamond shaped cutout shows the lower frequency than the plate with elliptical and rectangular cutout. The effect of fiber orientation angle depends on the boundary condition of the plate. As the cutout area increases, the fundamental frequency also increases, but for cantilever boundary, there is an inverse effect.

A computationally efficient C0 continuous finite element model for thermo-mechanical analysis of cross-ply and angle-ply composite plates in non-polynomial axiomatic framework

In the present article, the thermo-mechanical bending response of multi-layered composite plates is investigated in the framework of inverse-hyperbolic shear deformation theory using a generalized finite element model. The mathematical development is carried out under the assumptions of linear structural kinematics for the materials following generalized Hooke’s law. Energy-based finite element formulation and the principle of minimum potential energy are employed to develop the finite element governing equations. A computationally efficient C0 continuous finite element formulation is developed to examine the response of laminated composites subjected to constant, linear, and non-linear temperature change. Numerical analyses are carried out for composite laminates considering various lamination sequences (cross-ply as well as angle-ply), boundary conditions, loading conditions, span-thickness ratio, etc. The present results are compared with the existing analytical and numerical results and their agreement is observed. The effect of fiber orientation angle on bending response is analyzed to enable the optimal design of laminated composite structures under thermo-mechanical loading.

Effect of Fiber Orientation Angle on Stress Intensity Factor of Composite Plate Using Extended Finite Element Method (XFEM)

This paper presents the effect of fiber orientation angle on the stress intensity factor SIF for carbon epoxy composite plates with single-edge, center, and inclined cracks of varying lengths under tensile load. The stress intensity factor and shape factor were calculated individually for each case, with nine different fiber orientation angles computed using the extended finite element method XFEM concepts. It is found the stress intensity factor increases with increasing crack lengths while the shape factor decreases. In the case of single edge cracks, the SIF increases in the average value reached (173 %) for composite plates with different fiber orientation angles, while in the case of the center crack, the average value of SIF reaches (81 %). It was observed in this study that the increases in stress intensity factor and the decreases in the shape factor with different crack lengths were more stable in the composite plate with a fiber orientation angle of 75°. The higher values of SIF at an angle of 75° are because of the high probability of fiber slippage at 75° due to induced shear stresses in addition to the tensile stresses at the fiber-matrix interface. As a result, the crack tip has a high-stress intensity factor.

Modeling and implementation of finite element anisotropic flexural behavior of dielectric elastomer actuators reinforced with cross-angled fibers

The purpose of this paper is to investigate and develop the constitutive equation governing fiber-reinforced dielectric elastomers using finite element software because dielectric elastomers are a class of materials that undergo deformation when subjected to an electric field. As a result, due to this feature and widespread use in artificial muscles, it is very important to study their behavior. In the first step, the stress values are developed and calculated using invariants. Next, due to the nonlinearity of the material behavior, it is necessary to calculate the tangential modulus, which is one of the most important components in the analysis of the finite element model. Finally, according to the results, it is observed that the effect of fiber orientation angle on stress values is inevitable. How the anisotropic material bending rate will increase as the fiber orientation angle increases. Also, increasing the applied voltage, regardless of any orientation of the fibers, is associated with increasing the Kirchhoff stress in the direction shown in the figure.

The Study on Collapse Behavior and Crashworthiness Capacity of AL/CFRP Tubes Focusing on Fiber Angles and Stacking Sequence

This study has been aimed to investigate the effect of fiber orientation angle and stacking sequence on the collapse behavior and impact absorption capacity of hybrid tube. The specimens have been AL/CFRP composite materials made of cylindrical aluminum tubes (6063 -T5). The outer surface of the aluminum tube has been reinforced by wrapping with 1, 2 and 3 layers of Carbon Epoxy Fiber. The specimens have been tested with a dropped hammer of 30 kg weight and an impact speed of 6.905 m/s. Failure mode, maximum load, and average load from the test have been recorded. The FEA models of specimens have been also developed and tested with the same condition of experiment. The results have revealed that the AL/CFRP hybrid tube could resist higher impact loads than naked aluminum tube. The values maximum load and mean load were likely to increase according to the number of fiber layers, especially for the 3 layers hybrid tubes. It has been found out that the fiber angle of 45 degree had slightly effect to the load whereas the 0 and 90 degree angles have been much more effective. It has been also found out that stacking sequence has affected the pattern of failure and impact capacity considerably. The specimens with 90 degree fiber in the outer layers i.e. [0/90/90] and [0/0/90/90] have been found to provide the most crashworthy. It could be concluded that the combination and the stacking sequence of the fiber angles of 0 and 90 degree have highly affected the collapse mode and the crashworthiness capacity of hybrid tube.

Effect of fiber orientation angle on patch repaired composite plates

Abstract Stress intensity factors numerically investigated the Mode I loading of composite plates with an edge crack and repaired with a patch on a single side. The effect of the fiber orientation angle for both composite plate and the patch were analyzed with regard to crack length, adhesive properties, and plate thickness. The stress intensity factors were calculated by using the quarter point element that can be applied to 3D crack problems of homogeneous anisotropic materials.It was observed in this study that the fiber orientation angle affects the stress intensity factors significantly.

Elastic Buckling Response of a Composite Panel Stiffened Around Cutouts

Perforated composite panels are widely used in many engineering applications as subcomponents of complex structures including aircraft, ships, and other transport vehicles. In many of these applications, the primary objective of using the panel is to resist buckling. In this present study, a finite element analysis is performed adopting popular commercial software code Ansys on the buckling behavior of a simply supported quasi-isotropic symmetric composite panel with central circular cutouts, reinforced with stiffeners on both sides of the cutouts under uniaxial, biaxial and combined loading conditions. The main objective is to achieve the elastic buckling response of the perforated composite panels considering some important aspects of the stiffener as follows: (1) effect of the presence of reinforcement, (2) effect of stiffener area, (3) effect of stiffener thickness, (4) effect of stiffener material and (5) effect of fiber orientation angle. It is observed that reinforcement can significantly improve the critical buckling load of a panel, which is already reduced due to cutouts. Then, increasing the area of the stiffener does not have a major impact on the buckling stability of the panels. However, increasing the thickness can play a crucial role to strengthen the buckling stability. Finally, it is found that in comparison to aluminum and titanium alloys, epoxy-carbon is more practical as a stiffener material with correct fiber orientation angle (90°), considering the low weight increment and higher buckling achievability.

LOW VELOCITY IMPACT BEHAVIORS OF BASALT/EPOXY REINFORCED COMPOSITE LAMINATES WITH DIFFERENT FIBER ORIENTATIONS

The current study aims to explore the effects of fiber orientation angle on the low velocity impact behaviors of the basalt fiber reinforced composite laminates. Samples with four different orientation angles (0º/90º, 15º/-75º, 30º/-60º and 45º/- 45º) fabricated by vacuum assisted resin transfer molding have being tested on the Charpy impact test machine. Furthermore, failure modes of notched/unnotched samples subjected to impact loadings in the flatwise and edgewise directions have been examined to detailly understand fracture behavior. The results showed that the fiber orientation angle has substantial effects on the energy absorption capability and impact toughness of the samples. The increment in fiber orientation angle was led to increases in impact energy and toughness, and the reduction in impact damage. The best values as 3.07 J and 34.82 kJ/m2 for impact energy and impact toughness, respectively, are obtained from the notched samples in edgewise impact loading that having (45º/-45º) fiber orientation angle. Almost all of the samples exhibited failure modes as matrix fragmentation, delamination, fiber cracking and fiber pull-out, respectively. The most destructive results were observed as laminate fracture on the samples having (0º/90º) fiber orientation angle.

Free vibration studies on skew sandwich plates by FEM

Present study mainly deals with the extraction of fundamental frequencies using simply supported and clamped isotropic and laminated faced skew sandwich plates with the orthotropic core. Available literature values were referred to validate the fundamental frequencies obtained using the finite element method. The effects of aspect ratio, skew angle, a ratio of the length-to total thickness of the sandwich plate, and the ratio of a thickness of the core to a thickness of face sheet on the free vibration of skew sandwich plates were examined. The present method is also used to study the effect of fiber orientation angle and laminate stacking sequence on free vibration of antisymmetric cross-ply laminated skew sandwich plates are also extracted. CQUAD8 type of element gives converged, accurate results than the CQUAD4 element in the present study. The variation of frequencies is directly proportional with the skew angle.

Investigation of Effects of Fiber Orientation Angles on Deflection Behavior of Cantilever Laminated Composite Square Plates

In this study, the deflection response of cantilever laminated composite square plates subjected to the weight of itself was analyzed using finite element and Taguchi methods. The plates with 12 plies were made of glass fiber reinforced polymer composites (GFRP). The arrangements and fiber orientation angles of the plies were conducted using Taguchi’s L9 (33) orthogonal array. Each four plies was assumed to be control factor. Fiber orientation angles were varied from 10 to 90 in degree. Plates were modelled using finite element software ANSYS Parametric Design Language. Analysis of signal-to-noise (S/N) ratio was used in order to evaluate the control factors with the optimum levels for minimum deflection response. Analysis of variance was carried out in order to analyze the powerful influential control factors and their percent contributions on responses.

Numerical and statistical buckling analysis of laminated composite plates with functionally graded fiber orientation angles

The aim of this numerical and statistical study was to investigate the buckling analysis of laminated composite plates containing functionally graded fiber orientation angles. The laminated composite plates had functionally graded fiber orientation angles based on Taguchi’s L18 (21 × 32) orthogonal array. The fiber orientation angles were considered to be control factors. Numerical analyses were performed using finite element software ANSYS. The optimum critical buckling load and the effects of fiber orientation angles for maximum data were determined using the analysis of the signal-to-noise ratio. The importance levels of laminates and their percent contribution on the buckling characteristics were calculated using analysis of variance. Regression analysis was employed to investigate the effects of control factors on buckling responses mathematically. The effects of laminate stacking sequence, mesh size, element type, mode number, and boundary condition were carried out using laminates with the optimum levels.

BUCKLING TEMPERATURE ANALYSIS OF LAMINATED COMPOSITE PLATES WITH CIRCULAR AND SEMICIRCULAR HOLES

This statistical and numerical study deals with buckling temperature behavior of laminated composite plates with central circular and semicircular holes. Numerical buckling temperature analyses were performed using finite element software ANSYS based on Taguchi L18 orthogonal array. The plates were designed from graphite/epoxy systems. Fiber orientation angles and cutout shapes of the plates were assumed to be the control factors. Analysis of signal-to-noise ratio was used in order to investigate of the effects of fiber orientation angles and cutout shapes on the critical buckling temperature of the plates. Also, analysis of variance was performed in order to see percentage contribution rates and significance levels of control factors.

First Ply Failure Analysis of Laminated Composite Beam for Different Boundary Conditions Under Thermo Mechanical Loading

Failure analysis of a laminated composite beam subjected to uniformly distributed load and thermal load is studied for different boundary conditions and fiber orientation angles, based on first ply failure load. Three different boundary conditions are studied: simply supported, fixed-fixed and fixed-free. The strength ratio is computed and compared for different failure theories. The effect of fiber orientation angle and aspect ratio on the strength ratio based on first ply failure load is presented in the paper. The strength ratio and transverse deflection are determined for Graphite/Epoxy and Glass/Epoxy composite and their hybrid combinations to find out the optimum hybrid composite beam with minimum weight, deflection and cost. The problem is solved in MATLAB platform. The mode of failure of the composite beam is determined by using maximum stress theory.

Axial and lateral buckling analysis of fiber reinforced S-glass/epoxy composites containing nano-clay particles

In the present study, lateral and axial buckling characteristics of the S-glass/epoxy composites were investigated incorporating nano-clay (NC) particles within the common matrix of epoxy resin. Critical axial and lateral buckling loads of the composite samples were experimentally determined for different weight contents of NC particles (1, 1.5, 2 and 3 wt %). The effects of fiber orientation angles on critical buckling loads were investigated for both of axial and lateral buckling analyses, and it was shown that maximum axial and lateral buckling loads were obtained with fiber orientation angle of [0°/90°] and [15°/-75°], respectively. In addition, influence of NC particles on tensile and flexural properties were examined only for NC content of 1 wt %. It is concluded that incorporation of NC particles by 1 wt % in the composites resulted in 8.6% improvement axial buckling load, and further increasing NC content did not significantly effects on axial and lateral buckling values implying poor interfacial stress between NC particles and epoxy resin.

Stability analysis of composite thin-walled pipes conveying fluid

Stability analysis of a composite thin-walled cantilever pipe conveying fluid supported at free end by linear translational and rotational springs is considered in this paper. The governing equations of the system are developed by extended Hamilton's principle for open systems. Applying extended Galerkin technique, eigenvalue analysis is implemented and the critical fluid velocity and consequently stability of the system are obtained. The critical velocity and eigenvalue are validated by comparison with the results in available literature. The numerical results are presented to investigate the effects of fiber orientation angle, volume fraction of fiber, composite lay-up, size of fiber, structural damping coefficient, mass fluid ratio and elastic boundary conditions on eigenvalue and critical fluid velocity of the system. It is revealed that by increasing the value of fiber orientation angle, the critical fluid velocity of the system is decreased. Furthermore, it is found that the volume fraction of fiber and size of fiber have stabilizing effects on the dynamic behavior of the system. Moreover, it is demonstrated that by increasing the value of linear spring constant at the free end, the pipe loses stability by either divergence or flutter.

Effect of Fiber Orientation Angle on Stress Intensity Factor of Composite Laminated Crack Plate

Effect of Fiber Orientation Angle on Stress Intensity Factor of Composite Laminated Crack Plate

Effects of fiber orientation angles of fiber-reinforced plastic on sand solid particle erosion behaviors

Solid particle erosion in industrial applications has been a serious problem in many engineering fields. Earlier studies on fiber-reinforced plastic (FRP) composites were mainly focusing on the erosive wear behavior at several different impact angles. However, the effect of fiber orientation on FRP composites has not been thoroughly investigated. Since fiber orientation is one of the important factors in which causing erosive wear damages to FRP composites, in order to understand the virtue of this problem, it is important to investigate the effect of fiber orientation at different impact angles. In this research, the effect of fiber orientation of unidirectional fiber-reinforced plastic composites on erosive wear behavior was studied. Sandblasting-type erosion tests were conducted on the FRP composites with fiber orientation ranging at three impact angles to clarify the relation between fiber orientation and erosive wear behavior. The Dyneema fiber (ductile material) and the carbon fiber (brittle material) were used for the reinforcement fiber in FRP. From the result, it is confirmed that CFRP composites with higher fiber orientation angle erode faster than the composites with lower fiber orientation angle. But the erosion characteristic of DFRP was almost the same regardless of the fiber orientation angle. The damaged surfaces of the FRP composites were then analyzed using scanning electron microscopy and the possible erosion wear mechanisms were investigated.

Meso-scale study of non-linear tensile response and fiber trellising mechanisms in woven composites

The non-linear deformation response of plain woven carbon fiber-reinforced composites is experimentally studied at meso-scales. Stereovision digital image correlation is utilized to capture the full-field strain distribution over a 10 × 10 mm2 area of interest located at the center of the specimens. The evolution of local strains on the fiber bundles and matrix-rich regions as a function of loading is extracted. The effect of fiber orientation angle on fiber bundles stretch ratio and their angle of rotation (fiber trellising) and the related underlying failure mechanisms are analyzed using the measured full-field displacement data. The results indicate that the local load-bearing mechanisms are different in on-axis and off-axis loading conditions, whereas the larger global failure strain noticed in off-axis conditions is attributed to the occurrence of fiber rotation. The fiber trellising is also shown to promote high local shear strain and consequently leads to the protrusion of the matrix material on the deformed specimen surface.

A modified Fourier–Ritz solution for vibration and damping analysis of sandwich plates with viscoelastic and functionally graded materials

Most of the existing methods for sandwich plates are only suitable for a particular type of boundaries which typically require modifications in solution procedures to adapt different boundary cases. The main aim of this paper is to provide a unified yet accurate solution for vibration and damping analysis of viscoelastic and functionally graded (FG) sandwich plates with arbitrary boundary conditions. The two-parameter power-law distributions in terms of volume fractions are used for FG layer and a lamination theory is applied in composite laminated layers. The formulation is derived by the modified Fourier series in conjunction with Rayleigh–Ritz method according to the first-order shear deformation theory. The modified Fourier series is expressed in the form of the linear superposition of a double Fourier series and auxiliary functions which are introduced to ensure and accelerate the convergence of the series representations. The current method can be universally applicable to all classical boundaries, elastic boundaries and their combinations. New results about natural frequencies and loss factors of common and new types of sandwich plates are calculated, which may serve as benchmark solutions in future. The effects of some key parameters such as the boundary conditions, geometric properties and power-law indices on free vibration and damping characteristics of the plates are illustrated and analyzed. The effect of fiber orientation angle of composite facings on modal shapes is also investigated.