Hybrid Composite Plates Research Articles

Weight optimization of hybrid composite laminate using learning-oriented artificial algae algorithm

The optimal design of parameters is vital for the effective use of hybrid composite laminated structures. This is due to a highly dependent property of laminated composite structures strength on its fiber orientation, stacking sequence and the number of ply in each laminate. The main aim of this study is to apply Learning-Oriented Artificial Algae Algorithm for optimization of the weight of rectangular hybrid composite laminated plate subjected to compressive in-plane loading. The design parameters are number of plies and stacking sequence of the laminate. The critical buckling factor is the constraint of the optimization process. The parameters of the hybrid composite plate are optimized using Learning-Oriented Artificial Algae Algorithm with the aim of minimizing weight. The performance of the algorithm was compared with previous studies that employed the GA and ACO algorithms. The Learning-Oriented method is integrated to reduce the number of functions evaluated and in turn reducing computational cost. The results showed that Learning-Oriented Artificial Algae Algorithm outperformed GA and ACO, and hence can be successfully applied in the optimization of laminated composite structures.

Effect of Natural Fiber Loading on Mechanical Properties and Thermal Characteristics of Hybrid Polyester Composites for Industrial and Construction Fields

In the present work tensile, flexural, impact and hardness properties of sorghum bicolor, sisal fiber and jute reinforced with polyester composites are described for the first time. The hybrid composite plates are fabricated for different fiber weights by hand lay-up method. To investigate the mechanical attributes tensile, flexural, impact and hardness tests were performed as per ASTM standard. The mechanical test results revealed a regular trend of an increase in tensile, flexural, impact and hardness properties to adding natural fibers. Good adhesion between the natural fibers and the polyester matrix is also responsible for the effective resistance capability. Further, thermal stability and thermal decomposition of the composite material observed by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The work concludes that sisal, jute, and sorghum bicolor fiber have high potential as reinforcement for composite production. This type of composite material can be useful for automobiles, industrial applications and construction fields.

Damage Behavior of Hybrid Composite Plates Exposed to Impacts at Different Energy Levels

The impact behavior of hybrid composite plates cured at 120°C were examined by dropping weights on them for three hours. Two groups of hybrid composite plates were considered. In the first group (TYPE1), all plies were staked symmetrically or antisymmetrically with orientation angle 0°, but in the second group (TYPE2), plies were staked symmetrically or antisymmetrically with orientation angles 0° and 45°. The plates were subjected to impact loadings with energies of 12, 16, and 20 J. Deflections, contact forces, and absorbed energies were determined and compared for plates in the different groups.

The effect of cold environment on the buckling behavior of hybrid composites prepared by using carbon/aramid/glass

In this study, the effect of cold environment on the buckling behavior of hybrid composites kept at −18°C for certain periods was investigated. For the buckling tests, hybrid composite plates with different fiber combinations were produced using three different fibers—carbon twill, E-glass twill, and aramid twill—and an epoxy resin (Araldite/Aradur) as the matrix material. Specimens for the buckling experiments were cut from the 12-layer hybrid composite plates and the hybrid composite specimens were then divided into three different groups. The specimens in Groups I and II were kept in a refrigerator for 90 days and 150 days, respectively, while Group III specimens were kept under room conditions as the control group. The hybrid composite specimens were subjected to buckling tests as soon as their waiting times were over. The buckling behaviors of hybrid composites with different stacking sequences were examined on the basis of the data obtained from the buckling experiments. The load–displacement curves obtained from the experiments were used to calculate the critical buckling loads ( Pcrs) for each hybrid configuration. The Pcr was found to be highest for the hybrid configuration CAG (carbon/aramid/glass) with the stacking sequence [(0/−90)3]s and lowest for the hybrid configuration CAG45 with the stacking sequence [(45/−45)3]s. The hybrid composite specimens kept in a cold environment were found to have higher Pcrs than those kept under room conditions. The difference was greater in the case of the hybrid specimens kept in the cold environment for 150 days.

Investigating the effects of flax fibers application on multi-objective optimization of laminated composite plates for simultaneous cost minimization and frequency gap maximization

In recent years, the application of flax fiber reinforced composites has attracted much attention from the automobile and construction industries. From the composites reinforcement point of view, the flax fiber is an efficient alternative to the glass fiber in terms of the cost, mechanical properties and environmental effects. The current study investigates the multi-objective optimization of hybrid laminated composite plates with objective functions of minimizing the cost and maximizing frequency gaps. In order to assess the capabilities of the flax fibers in reinforcing composites, a set of multi-objective design optimization problems of hybrid composite plates with discrete design variables of material types and fiber orientations are investigated. Numerical results obtained from the hybrid graphite-glass/epoxy and graphite-flax/epoxy composite plates with different aspect ratios demonstrate that the application of flax fibers can not only reduce the cost and increase the fundamental frequency, but also provide the optimum designs with bigger gaps between two consecutive natural frequencies.

Investigation of the Acoustic and Mechanical Properties of Homogenous and Hybrid Jute and Luffa Bio Composites

ABSTRACT Design and development of new biomaterials has become a necessity due to adverse effects of chemical materials on people and nature. As the mechanical properties of biomaterials are not as good as those of chemical materials, their different configurations should be developed and tested before considering them for practical applications. Acoustic and mechanical properties of homogenous and hybrid jute and luffa biocomposites are investigated here. Homogenous and hybrid composites using jute and luffa fibers and epoxy are designed and manufactured and methods for identification of the acoustic and mechanical properties are summarized. Acoustic and structural frequency response functions are measured using homogenous and hybrid composite plates to determine their natural frequencies and loss factors. Using the experimental modal parameters of the plates and their theoretical models, elasticity moduli of biomaterials are determined. The acoustic absorption properties and transmission losses of homogeneous and hybrid composites are determined using impedance tube method. Results show that homogenous and hybrid jute and luffa composites can have moderate absorption coefficients (0.1 for a thickness of 4 mm) and superior damping performance of luffa and stiffness property of jute can be used together to produce hybrid composites with high damping (2.2–2.6%) and elasticity modulus (3–5 GPa).

The dynamic performance of novel multilayered hybrid composite laminate

Due to an increase in the need for improvement of impact resistance of conventional composites, hybrid composites are evolved. This research article presents the dynamic characteristics of a novel two-component hybrid composite plate under transverse impact loading. The multilayered hybrid composite laminate is fabricated using woven fibreglass fabric as skin material and thermoplastic polycarbonate sheet as the core. High strength, medium viscous epoxy matrix is used for bonding the skin and core materials. The hand layup followed by a compression molding technique is used for producing the laminate. The test samples are impacted with a minimum energy of 45 J to a maximum energy of 60 J to obtain rebound, penetration and perforation phenomenon at room temperature. Load–energy–displacement–time curves are plotted to understand the transient behaviour of the composite plates. Results are compared with the pure counterparts available in the literature in terms of impact resistance. It is inferred that the novel multilayered laminate being in lightweight about 19.17% as compared to conventional laminate presented by Evci and Gulgec (J Compos Mater 48:3215–3236). Further, the novel composite has provided less damage area with 16.66% of enhanced impact resistance in terms of energy required for complete perforation. The investigation revealed the possibility of replacing conventional materials with hybrid laminates in structural, defense and automotive applications, where impact resistance and light weight has much importance.

Vibration and stability of initially stressed functionally graded carbon nanotube-reinforced hybrid composite plates in thermal environments

The vibration and stability of hybrid functionally graded (FG) composite plates subject to an arbitrary initially stress in thermal environments is investigated. The plate is reinforced by single walled carbon nanotubes (CNTs). Various profiles of CNTs distributions and volume fractions of hybrid nanocomposite plates are considered. Based on the perturbation method, the governing equations for the hybrid nanocomposite plate considering the effects of non-uniform initial stresses are established. The effects of the CNTs volume fraction, CNTs distribution type, layer thickness ratio, temperature and initial stress on the buckling loads and natural frequencies of hybrid nanocomposite plates are studied in detail.

The nonlinear deflection response of CNT/nanoclay reinforced polymer hybrid composite plate under different loading conditions

The carbon nanotubes (CNTs) are used as significant reinforcement materials in the advanced composites due to their improved mechanical properties. The carbon nanotubes reinforced nanocomposites have improved mechanical strength, and stiffness properties in addition to their reduced weight. Only a few percentages of CNTs (2–5% by weight) could be added to these nanocomposites as more volume fraction will deteriorate their mechanical properties. A computational approach is used in the present investigation to find the mechanical properties of the hybrid nanocomposite which is modeled by adding nanoclay particles into the conventional CNTs reinforced epoxy system. Using Halpin-Tsai approach (which is based on the micromechanical modeling) the mechanical properties of hybrid nanocomposites are evaluated. The effect of the CNTs and the nanoclay particles on the nonlinear transverse central deflection response of nanocomposite plate under different loading conditions is studied in detail. The simulation results of present investigation have been validated with the data sets of the deflection responses available in the references.

Balistik Darbe Yükleri Altındaki Nano Yapılı Hibrit Plakaların Davranışları Üzerine Bir Çalışma

Hybrid composites are the material group largely preferred for use in space, aerospace and ballistic applications, where superior mechanical properties and low density are required. Hybrid composites produced using high-strength Kevlar fiber and S-glass fiber materials and nano particle added matrix in this study. Nineteen combinations of hybrid composite materials were produced using three matrix materials—nano-calcite, nano-clay and carbon nano-tube which have high-energy absorption properties. To compare the ballistic test results of hybrid composites, 1 control sample were tested. Nano particles were added into the composites in the ratio of 0.5, 1 to 2 percent, corresponding to the ratios that achieved the most desirable mechanical properties in other literature. Deflections occurring at composites’ back surfaces were measured after tests and evaluation of whether there would be perforation was done. As a result of this study, was seen that ballistic strength positively affected with nano particle addition and different stacking sequences of composite layers. In hybrid composites produced by S-glass reinforcement, the weight decreased by 20% while the ballistic strength decreased significantly. It was found that calcites adding hybrid composite plates at the front sites and clay added plates at the back sites showed superior ballistic performance. It was observed that the ballistic strength of hybrid composites increased with increasing calcite ratio at the front sites.

Finite element modelling of carbon fiber - carbon nanostructure - polymer hybrid composite structures

The present study deals with the numerical modelling of hybrid laminated composites, which can be proved especially useful in the engineering and maintenance of advanced aerospace primary structures. The lamina is comprised of continuous carbon fibers, thermosetting epoxy polymer matrix, as well as carbon nanostructures, such as graphene or carbon nanotubes, inclusions. Halpin-Tsai equations combined with results obtained from nanomechanical analysis are employed in order to evaluate the elastic properties of the carbon nanostructure/polymer matrix. Then, the obtained elastic properties of the hybrid matrix are used to calculate the orthotropic macro-mechanical properties of the unidirectional composite lamina. A hybrid composite plate is modelled as a 2D structure via the utilization of 4-node, quadrilateral, stress/displacement shell finite elements with reduced integration formulation. The convergence and analysis accuracy are tested. The mechanical performance of the hybrid composites is investigated by considering specific configurations and applying appropriate loading and boundary conditions. The results are compared with the corresponding ones found in the open literature, where it is possible.

Buckling Analysis of Inter-ply Hybrid Composite Plate

Abstract Present work mainly deals with the buckling analysis of inter-ply hybrid composite plate which is made by the combination of one natural and two synthetic unidirectional fabrics and epoxy resin. Finite element method is used to predict the buckling behavior of composite plate with [(0/90)3]S , [(45/-45)3]S , [(30/-60)3]S symmetrical and [(0/90)3]US , [(45/-45)3]US , [(30/-60)3]US un-symmetrical ply orientation and FCA, FAC, CFA, CAF, AFC and ACF ply sequence (order) . Modelling and analysis of composite plate are performed in ANSYS 16.0 software to determine the best ply orientation and sequence of ply under buckling case. It is concluded that symmetric [(0/90)3]s ply orientation and CAF ply sequence is best suited for buckling of composite plate

Concurrent multi-scale optimization of hybrid composite plates and shells for vibration

In this paper, a concurrent multi-scale optimization framework is established for hybrid composite plates and shells, where fiber volume, fiber orientation and stacking sequence can be optimized simultaneously. Firstly, a finite element model of shell structure that contains patches is established. Then, the candidate material set of hybrid composites is calculated and assembled by different combinations of fiber volume, fiber orientation and stacking sequence at the material and laminate scales. Furthermore, the Discrete Material Optimization (DMO) method is employed to perform the concurrent multi-scale optimization. Two illustrative examples are used to verify the effectiveness of the proposed optimization framework, including a simple example of a hybrid composite plate and a complex engineering example of a double serpentine nozzle. In comparison to optimal results by the traditional constant-stiffness design method, the optimal results of the proposed framework achieve significant 19.8% and 14.0% improvements in the fundamental frequency under the constraint of material cost, respectively. It can be concluded that the proposed concurrent multi-scale optimization framework has huge potential in adaptive stiffness tailoring for hybrid composite plates and shells with complex multi-scale design variables, which can make full use of hybrid composite materials to improve the structural performance against vibration while maintaining the low material cost.

Buckling and postbuckling response of hybrid composite plates under uniaxial compressive loading

In this study, experimental and numerical investigations of buckling and postbuckling responses of square symmetric plates configured with innovative layup sequences have been conducted under uniaxial compressive loading. Effect of stacking sequences and orientation of fibers on buckling and postbuckling responses of fiber reinforced polymer (FRP) plates made of unidirectional carbon and glass fibers are investigated. Initially, plates with fiber aligned in (0/90) directions are fabricated and tested under uniaxial compressive loading, with simply supported boundary conditions. Later, the plates are modeled and analyzed with FEM based software ABAQUS, and a parametric study is performed with various fiber orientations. The plates considered are plain CFRP, plain GFRP, functionally graded hybrid (FH) and sandwich hybrid (SH). Amongst the stacking sequences, such as (0/90)4s, (-45/+45)4s, and (-45/+45/0/90)2s, the functionally graded hybrid (FH) plate with fiber stacked in (-45/+45/0/90)2s directions showed highest buckling and postbuckling strengths. First ply failure was predicted by incorporating the Tsai-hill failure criterion in the numerical analysis. It is observed that plates with glass fibers in the core region have high strength, and the strength significantly depends on the type of plate and fiber orientation. This type of strength enhancement has been observed in all the plate types, i.e., functionally graded hybrid and sandwich hybrid plates. It is further observed that the numerically investigated results are in good agreement with experimentally obtained values. Buckling and postbuckling responses are also investigated for functionally graded hybrid plates with various shaped and sized cutouts, using similar loading and boundary conditions. Circular, diamond, horizontal ellipse, vertical ellipse, and square shaped cutouts were considered in three different sizes (small, medium, and large). It is observed that plates with a smaller size elliptical shaped cutout aligned horizontally and located at the center of the plate have highest buckling, first failure, and ultimate failure loads.

Primary and Secondary Instability Region Analysis of Rotating Carbon Nanotube–Reinforced Non-Uniform Hybrid Composite Plates

In this work, the primary and secondary instability region analysis of rotating multi-walled carbon nanotube (MWCNT) reinforced non-uniform hybrid composite plates (CNT-FRP) under uniaxial periodic loads is performed. First-order shear deformation theory has been used to derive the kinetic and potential energy equations of the various configurations of non-uniform composite plates by including the effect of rotary inertia, shear deformation, varying centrifugal stiffness and non-uniformity along the transverse direction of the plate. The governing differential equations of motion are derived in the form of Mathieu–Hill equations using the Hamilton’s principle. The efficacy of the developed finite-element formulation has been verified by comparing the natural frequencies of the rotating composite plates evaluated using the numerical simulation with the experimental results and available literature. This study also investigates the influence of the CNT vol%, CNT aspect ratio, angular rotation of plate and static load on the primary and secondary instability region of various non-uniform configurations of CNT-FRP hybrid composite plates. It was noticed that the primary and secondary regions of parametric instability of CNT-FRP hybrid composite plates shift upward when CNT vol% increases from 0 to 2%. It was further noticed that primary and secondary instability regions of various non-uniform configurations shift to the lower excitation frequency when MWCNT vol% increases beyond the saturation limit. It was observed that the effect of angular rotation and static load is significant on the primary and secondary regions of instability.

Investigation of Ballistic Behavior of Agricultural Waste Doped Hybrid Composite Plates in Vacuum Infusion Method

The vacuum infusion method is used in the production of ballistic composite materials, in the repair of aircraft parts and in the production of layered hybrid composite materials. In this study, production of hybrid composite materials including apricot kernel shell powder, hazelnut shell powder, walnut shell powder and graphene nanopowder added layer were made by vacuum infusion method. Layered hybrid composite samples with pure graphene nanopowder added and different shell powder added were produced. Then the produced hybrid composite samples were subjected to ballistic experiments. Due to the security, only the photographs of the ballistic test results were allowed to be shared.

Assessment of dynamic properties of hybrid ribbon reinforced multifunctional composite sandwich plates: Numerical and experimental investigation

Abstract This study investigates numerically and experimentally the effect of longitudinal ribbon reinforcement in conventional honeycomb structure on the various dynamic characteristics of a hybrid composite sandwich plate. Longitudinal strips are considered to be embedded along the transverse directions at various locations of a honeycomb core material without and with carbon nanotubes (CNT) reinforcement in a composite sandwich plate. The governing differential equations of motion of the various hybrid honeycomb composite sandwich plate configurations with strips inserted in conventional honeycomb structures as core layer having top and bottom face composite layers are derived using higher order shear deformation theory (HSDT) and solved numerically using a four noded rectangular finite element. Further, experimental investigations are performed by fabricating the various strips embedded hybrid honeycomb core material with and without CNT reinforcement to evaluate the shear and loss moduli using the alternative dynamic approach. The efficacy of the developed finite element formulation is demonstrated by comparing the experimental and numerical results obtained in terms of natural frequencies and loss factors for the various prototypes of honeycomb composite sandwich plates. Also, the effect of variation in CNT content and thickness of longitudinal ribbon reinforcement in conventional honeycomb core material and ply orientation of the face sheets on the various dynamic properties of hybrid composite structures are studied under various end conditions. This study proposes that the ribbon reinforcement location and the addition of CNTs in honeycomb core materials strongly influence the stiffness, damping and transverse vibration displacements of the ribbon reinforced hybrid composite sandwich plates.

Modeling the Dynamic Bending of Rigid-Plastic Hybrid Composite Curvilinear Plates with a Rigid Inclusion

A general method has been developed for calculating the dynamic behavior of rigid-plastic composite layered fibrous plates with a rigid inclusion and with the hinged or clamped arbitrary smooth non-concave curvilinear contour subject to a uniformly distributed short dynamic explosive loading of high-intensity. The distribution of layers is symmetric with respect to the middle surface, and in each layer there is a family of reinforcement curvilinear fibers in the directions parallel and normal to the plate contour. The structural model of the reinforcement layer with a one-dimensional stress state in the fibers is used. Depending on the loading amplitude, different types of plate deformation are possible. Based on the principle of virtual power in combination with the d’Alembert principle, the equations of dynamic deformation are derived and their implementation conditions analyzed. The analytical expressions for assessing the limiting loads, deformation time, and residual deflections of the plates are obtained. It is shown that the variation in the reinforcement parameters significantly affects both the loading capacity of such plates and the residual deflections. Examples of numerical solutions are provided.

Concurrent Patch Optimization of Hybrid Composite Plates Based on Proper Orthogonal Decomposition

Hybrid composite materials, which contain more than one type of reinforcing fiber, have been gaining ever-increasing popularity. They can keep superior mechanical properties while greatly reducing the material cost. To fully explore the load-carrying potential, it is crucial to develop a series of corresponding optimization methods for hybrid composites design. In this paper, the concurrent patch optimization of hybrid composite plates is investigated, where fiber orientation, the stacking sequence, and material topology are optimized simultaneously. Discrete material optimization (DMO) is performed to optimize the hybrid composite plates, with the buckling load as the objective and the material cost as the constraint. Because the effectiveness of DMO has been demonstrated to perform the discrete variable optimization of composite structures. Furthermore, an innovative DMO framework based on proper orthogonal decomposition is established to reduce the computational cost, with the aim being to improve the optimization efficiency by reducing the order of the corresponding finite element model, and thus the time needed for the finite element analysis. The effectiveness of the proposed method is demonstrated by means of an illustrative example wherein both the material cost and the time needed for the buckling analysis are reduced dramatically.

Damage investigation and assessment due to low-velocity impact on flax/glass hybrid composite plates

There is limited information available in the body of knowledge regarding to the low velocity impact damage characteristics of sustainable bio-based such as flax fibre reinforced composites. This paper presents the results of full investigation of impact damage mechanisms on flax/vinyl ester laminated composite and flax-glass/vinyl ester hybrid composite laminates caused by low-velocity impact using a drop weight impact machine. The specimens were subjected to incident energy levels of 25 J and 50 J, in order to achieve a damage up to perforation and complete penetration. A 3D Finite Element Analysis (FEA) model was also developed using Hashin failure criteria. The damage and the predicted delaminations were compared using a high-resolution micro-Computed Tomography (μ-CT) technique. The results of the numerical analysis correlated well with the experiments and the imaging, which provided a full verification of the exact position of delaminations due to impact within the composite laminates.