Composite Material Plate Research Articles

Comparison of experimental and numerical analysis of Quasi-Static punch shear test for stainless steel sheet material

In this study, Quasi-Static Punch Shear Test (QS-PST) for AISI-304 stainless steel sheet material with 0.5 mm thickness was performed experimentally and numerically, then the results were compared. QS-PST was designed non-standard according to the need and is especially used to determine the puncture resistance of composite plate materials against low-speed loading. Since the results obtained from QS-PST are similar to those from ballistic tests, this has attracted the attention of researchers. The experimental study was carried out by integrating the die and punch which were specially produced for this test, into an electromechanical tensile-compression test device with a capacity of 100 kN. In order to define the material properties correctly in numerical analysis, the tensile tests of the relevant material were also carried out with the same device. Then, the CAD model of the experimental system was generated and Finite Element Analysis (FEA) was performed. In FEA, the mesh structure was determined as tetrahedral, since it gave closer results in such tests and the analyzes were performed by increasing the number of mesh from 16700 to 151800 elements. Finally, the experimentally and numerically obtained results were compared and it was observed that the result were very close depending on increasing the number of mesh.

Plane waves in microstretch elastic solid with voids

A linear theory of microstretch elastic solid containing uniform distribution of uniform voids has been formulated. Constitutive relations are developed by constructing suitable strain energy density function from the basic state variables. Then using the principles of mechanics, the field equations are derived for isotropic homogeneous microstretch elastic medium containing voids. The possibility of propagation of plane waves is explored and found that there may exist four sets of coupled dilatational waves and two sets of coupled transverse waves traveling with distinct speeds. The coupled longitudinal waves are found to be attenuating and dispersive, while the coupled transverse waves are dispersive but non-attenuating in nature. The coupled transverse waves are found to be independent of the presence of stretch and voids in the medium. The attenuation of coupled longitudinal waves arises due to the presence of dissipation coefficient of void volume fraction. In case of Voigt model, only the coupled transverse waves arising due to the microrotation disappear below their respective critical frequency, while in case of non-Voigt model, three sets of coupled longitudinal waves and one set of coupled transverse waves corresponding to predominantly due to the microrotation are non-progressive waves below their respective critical frequencies. Some limiting cases have been discussed and explained. Numerical computations have been carried out for Gauthier composite plate material and the results are displayed graphically.

Analysis the dispersive nature of Love wave in fibre‐reinforced composite materials plate: A Green's function approach

The research article mainly focuses on investigating the dispersive behaviour of Love waves influenced by an impulsive point source in a fibre‐reinforced magnetoelastic (FRME) plate placed on functionally graded fibre‐reinforced visco‐elastic (FGFRVE) semi‐infinite stratum. The materials of the considered structure have been assumed under the influence of magnetic field and functionally graded. The functionally graded in the lower semi‐infinite space is caused by consideration of quadratic variation in the shear moduli and mass density. Maxwell's equation and generalised Ohm's law have been employed to calculate the Laurentz force in the fibre‐reinforced magnetoelastic (FRME) plate. For solving the coupled field equations, three‐dimensional Green's function and Fourier transform are applied; consequently, the closed‐form of the Love wave's dispersion relation is obtained. The obtained dispersion curve is plotted and compared in the numerical results and discussions by taking the different magnitude of materials quantities such as reinforcement parameter, magnetoelastic coupling parameter, functionally graded parameter, and visco‐elastic parameter. In some particular cases, the deduced dispersion equation is found to be identical to the classical Love wave equation for uniform homogeneous isotropic cases, indicating that the assumed structures are valid. The obtained results from the entire study can be utilised to better understand the dispersive nature of Love wave propagation in the considered systems containing fibre‐reinforced, magnetoelastic, viscoelastic, and point sources.

Acoustic sources localization for composite pate using arrival time and BP neural network

This paper presents a machine learning approach to localizing a five-peak narrow-band modulated sinusoidal signal excitation source within a composite panel. In particular, the Back Propagation (BP) neural network is used. The idea is to use the arrival time of the first wave packet in a five-peak wave signal to locate their source. Specifically, this paper divides the composite material board into multiple regions, designs 8 receiving points to receive the signal from the excitation source, and finds the region where each source is located. The COMSOL numerical simulation platform is used to build a composite plate model and simulate the propagation of five-peak waves to train and test the machine learning network. Correspondingly, carry out experimental verification and use a scanning laser Doppler vibrometer (SLDV) to build a non-contact experimental platform to obtain the wave field information in the composite material plate. The results show that BP neural networks can learn to map signal features to their sources in both contexts.

Numerical simulation and constructal design applied to biaxial elastic buckling of plates of composite material used in naval structures

Thin plates when subjected to compressive loads can present a structural instability phenomenon known as buckling, causing displacements out of the plane of the plate. In addition, it is known that the use of composite materials in naval engineering can bring many benefits in the medium and long term, like the major corrosion resistance, when compared with steel structures. Moreover, for specific applications perforated plates are necessary, like passage of cables and pipes, inspection windows, among others. Therefore, to find the optimal geometry of a composite plate with a centered elliptical hole the Constructal Design (CD) was applied in association with the Exhaustive Search (ES) technique and Finite Element Method (FEM). The CD allows the evaluation of the geometry that provides the optimal distribution of imperfections, leading to the maximum value of the performance parameter used for the analysis of solids mechanics problems. Applying different laminations, it was observed an increase in the critical buckling load for a composite plate without perforations of up to 10.47%. In its turn, despite suffering a reduction in the critical load value if compared to the plate without holes, an improvement of 16.89% was observed when optimal and worst geometries for the perforated plates are compared.

Effects of carbon nanotubes on mechanical behavior of fiber reinforced composite under static loading

AbstractThe purpose of this research article is to show the effect of carbon nanotubes (CNTs) addition on fiber reinforced polymer matrix composites produced by the vacuum infusion method on tensile performance. In this study, glass, carbon, and fiber fabric reinforced polymer matrix composite plates were produced using glass, carbon and aramid fiber fabrics with the same weave type and similar areal density. Using the same production parameters, the composite plates reinforced with different fiber types were produced with CNTs addition by 0.5 wt% of total composite. Additionally, since it is thought that the effect of CNTs on performance in different fiber types may be different, hybrid fiber fabric reinforced composite plate material containing a composition of glass, carbon and fiber fabrics was produced and this material was produced with CNTs additive using the same production parameters as in previous fiber reinforced composite plate productions. In the study, composite plates with and without CNTs were produced in various compositions including glass, carbon, aramid, and hybrid fiber fabrics. As a result, CNTs reinforcement has increased the mechanical performance under tensile stress in glass, carbon, and hybrid reinforced fabric composite structures, but on aramid fiber, CNTs has decreased the performance.

Acoustic response analysis of periodic orthogonal stiffened composite sandwich structure with pyramidal truss cores

This paper presents analytical studies on the sound transmission loss behavior of functionally graded carbon nanotube reinforced composite (FG-CNTRC) truss core sandwich structure plates subjected to plane sound wave excitation, wherein three different functionally graded patterns are introduced for the carbon nanotubes through the thickness direction of structures. The effective CNTs material properties for each type are determined by the extended rule of mixture and the governing equations are based on the first order shear deformation theory. The compatibility of displacements on the interface between the plate and the stiffeners is employed to derive the governing equation of each stiffener. By using the modal expansion approach and Rayleigh integral, the sound transmission loss is described analytically. Since no existing results of sound insulation can be found for such composite material plate structure, experimental measurements of composite stiffener sandwich plate which is composed of carbon fiber reinforced composite material are subsequently carried out to validate the theoretical model, and good agreement is achieved. Based on the developed theoretical model, the influences of the volume fractions of CNT, truss core type, distribution type of CNT, stiffener spacing, and truss core height on sound transmission loss are subsequently presented.

Composite-to-metal multi-bolt joints: a simplified FE analysis method

This paper presents a modified version of the Composite Bolted Joint Element (CBJE) that can be employed for the finite element analysis of double-lap joints made up of metal and composite material plates. The CBJE makes use if the theoretical definition of composite bolted region that is solved to analytically define the behavior of the joint. The solution is utilized to obtain the stiffness of the bolted region and the bolt-hole contact stiffness that are transferred to the CBJE. The definition based on the analytical solution allows to balance the accuracy and the computational effort of the solution. The results of CBJE for hybrid double-lap joints is compared with a 3D FE solid demonstrating a highly remarkable matching.

The effect carbon nanotube on three-point bending behavior of fiber reinforced composite

The aim of this research article is to show the effect of Carbon Nanotube (CNT) additive on the performance of composite plate materials with fiber reinforced polymer matrix produced by vacuum infusion method under bending test. In this study, multiple layered composite plates have produced by glass, carbon, and aramid fiber reinforcements with 0.5% CNT addition by mass. In addition, a hybrid composite plate containing glass, carbon and aramid (Kevlar) fiber has produced with CNT addition by using the same production parameters. Three point bending test has performed on the composite plates under 1 mm/min bending with ASTM D7264 standard. As a result, CNT addition has increased the flexural performance but has decreased the elongation of glass and carbon fiber reinforced systems. In aramid reinforced system, both flexural strength and elongation has increased. However, in the hybrid fiber reinforced system, different fiber types have damaged at different elongation distances within the structure under different loads, and gradually more than one failure have observed. When the CNT has added to the hybrid system, the elongation increased but the flexural strength has decreased.

Modeling of thermal stresses in thin-walled composite structures with phase transformation

An asymptotic theory modified version for calculating thin elastic multilayer plates made of high-temperature composites with multistage phase transformations, considering the composites shear characteristics finite values has been developed. Proposed in this work method version does not contain any assumptions about the kind of the unknown functions and allows ones to find all 6 stress tensor components while ensuring the high mathematical accuracy that symbolic for asymptotic method. Using the developed model, it became possible to calculate temperature non-stationary field and thermal stresses in thin multilayer plates of fabric composite materials on an inorganic binder. For material properties calculation were used multiscale averaging method and finite element modeling for periodical cells. Some change stresses numerical simulation results for composite plate during heating and loading are given.

Analysis of nonlinear vibration of magneto-electro-elastic plate on elastic foundation based on high-order shear deformation

Considering the condition of the elastic foundation and obeying Reddy's third-order shear deformation theory, the nonlinear forced vibration behavior of the magneto-electro- elastic composite materials (MEE) plate is studied. Combined with von Karman's nonlinear principle and Hamilton's principle for model derivation, the nonlinear partial differential equations of the MEE plate are obtained, and then the equations obtained are dimensionless. Based on the mechanical model of the nonlinear forced vibration of the MEE plate and the Galerkin method, the nonlinear high-order partial differential equations are reduced the two-degree-of-freedom nonlinear ordinary differential equations and the model is analyzed by the multi-scale method. In the numerical calculation, the influence of the geometrical parameters, loads, damping, magnetic and electric field strength of the MEE plate on the nonlinear amplitude-frequency response curve (AFRC) of the MEE plate is discussed.

Pin loading effect on 3D spacer fabric-laminated composites produced vacuum infusion

In this study, pin-loading behavior of laminated composites reinforced with three-dimensional (3D) spacer fabric was investigated, experimentally. Failure loads and modes of 3D-woven glass fiber epoxy composites, which are mostly preferred in automotive, machinery, and building production, are determined and compared with the mechanical properties of two-dimensional (2D)-woven fabric-reinforced composite materials. For this purpose, 2D plane and 3D spacer fabric composite plates were produced using the vacuum infusion method. The effect of pin geometry on joint strength and failure mechanism of composite was determined by tensile tests using test apparatus of single and two serial pin joint. In addition, low velocity impact tests of 2D and 3D plates were performed to explain the failure behavior. For mono-layer 3D-woven fabrics, the existence of out-of-plane fiber increases failure strength up to 50% compared to 2D fabrics. On the other hand, the use of multi-layer 3D fabric does not affect changes-specific failure load according to 2D fabrics significantly. Increasing in the specific load is only 9% for two-layers 3D. This situation has also been observed in impact tests.

RETRACTED: Thermal characterization of composite material plates ceramic/metal FGM

The sudden change in material properties across the interface between various materials can cause solid interlayer focuses on that lead to boundary, breaking, and other harm instruments. To address these inadequacies, Functional Gradation Materials have been proposed, through which the properties of the materials are reliably unique. The point of this article is to dissect the mechanical warm twisting conduct of thick artistic/metal sheets. This work presents a layout that utilizes the new cross-over shear usefulness. The mathematical outcomes got through the current investigation are introduced and contrasted and those accessible in the writing. It very well may be inferred that this hypothesis is viable and straightforward for static plate investigation in warm conditions.

Piezoelectric Transducer-Based Diagnostic System for Composite Structure Health Monitoring

This paper focuses on the investigation of the diagnostic system for health monitoring and defects, detecting in composite structures using a piezoelectric sensor. A major overview of structural defects in composite materials that have an influence on product performance as well as material strength is presented. Particularly, the proposed diagnostic (health monitoring) system enables to monitor the composite material plate defects during the exploitation in real-time. The investigated health monitoring system can indicate the material structure defects when the periodic test input signal is provided to excite the plate. Especially, the diagnostic system is useful when the defect placement is hard to be identified. In this work, several various numerical and experimental studies were carried out. Particularly, during the first study, the piezoelectric transducer was used to produce mechanical excitation to the composite plate when the impact response is measured with another piezoelectric sensor. The second study focuses on the defect identification algorithms of the raw hologram data consisting of the recorded oscillation modes of the affected composite plate. The main paper results obtained in both studies enable us to determine whether the composite material is characterized by mechanical defects occurring during the response to the periodic excitation. In case of damage, the observed response amplitude was decreased by 70%. Finally, using the time-domain experimental results, the frequency response functions (FRFs) are applied to damage detection assessment and to obtain extra damage information.

Coupling mechanism of highly nonlinear solitary waves with damaged composite material plates

The coupling interaction between nonlinear solitary waves in one-dimensional granular chains and damaged composite material plates is considered. Based on Hertz contact law and meso-mechanical model of stiffness reduction of composite material plates when the fiber breakage is the main damage mode, the coupled differential equations of particle chains and damaged composite material plates are derived. By solving the differential equations with Runge–Kutta method to get the velocity and displacement curves of particles and analyzing the delays and amplitude ratios of reflected waves, it is found that the damage quantity, fiber volume fraction, and thickness of damaged composite material plates as well as gravity have an effect on solitary waves. The preliminary research results provide a theoretical basis for nondestructive testing of damaged composite material plates by using solitary waves.

Research on flexural performance of damaged RC beams strengthened by FPR plates

Combining two technologies of pasting fiber reinforced composite board (FRP) and externally reinforced steel plate concrete structure, fiber-reinforced composite material and steel plate composite reinforced concrete structure technology can effectively improve the stress performance of concrete reinforced structure. To explore the effect of the new technology steel plate anchoring FRP slab concrete beams and the effect of different damage levels on the reinforcement effect, in this paper, the author made 3 FRP reinforced beams with damage rates of 20%, 40%, and 60%, 1 RC beam with FRP plate only and an ordinary RC beam to analyze the reinforcement effect of the new process steel plate anchored FRP plate and the bearing capacity and plastic performance of the reinforced beam with different damage rates. The results show that the new technology steel plate anchoring FRP plate reinforcement technology can effectively prevent the occurrence of early peeling failure, improve the ductility and bearing capacity of the reinforced beam, and significantly increase the utilization rate of the FRP plate; as the damage rate increases, the ultimate bearing capacity of the reinforced beam increases, but the ductility is significantly reduced.

Experimental study of thermal behavior of heated Natural Composite Materials

An experimental investigation was carried out for the thermal behavior of horizontal heated natural composite material plates; (polyester resin mixed with seed dates, or egg shells, or and feathers) with different volume fraction (10%, 20%, and 30%). Natural composite materials are heated with different heat flux (1078W/m2, 928W/m2, 750W/m2, 608W/m2 and 457W/m2). Experimental test rig is used to measure the temperature distribution upper surface of composite materials. Also the thermal properties (thermal conductivity, specific heat, and thermal diffusivity) of natural composite materials are studied. The results show that the maximum value of temperature occurs at the mid- point of the all types of natural composite material plate when the volume fraction equal to 30% and the heat flux equal to 1078 W/m2. Results show that the thermal conductivity for seed dates composite material, the specific heat for feathers composite material and the thermal diffusivity for seed dates composite material are higher value when the volume fraction equal to 30%.

Investigation of cotton fabric composites as a natural radar-absorbing material

PurposeThe purpose of this paper is to investigate cotton fabric behavior that is exposed to radar waves between selected operation frequencies as an alternative radar-absorbing material (RAM) response. Cotton fabric biocomposite materials were compared with carbon fabric composite materials, which are good absorbers, in terms of mechanical and electromagnetic (EM) properties for that purpose.Design/methodology/approachThe laminated composite plates were manufactured by using a vacuum infusion process. The EM tests were experimentally performed with a vector network analyzer to measure reflection, transmission and absorption ability of cotton fabric, carbon fabric and cotton–carbon fabric (side by side) composite plates between 3 and 18 GHz. The tensile and low-velocity impact tests were carried out to compare the mechanical properties of cotton fabric and carbon fabric composite plates. A scanning electron microscope was used for viewing the topographical features of fracture surfaces.FindingsThe cotton fabric composite plate exhibits low mechanical values, but it gives higher EM wave absorption values than the carbon fabric composite plate in certain frequency ranges. Comparing the EM absorption properties of the combination of cotton and carbon composites with those of the carbon composite alone, it appears that the cotton–carbon combination can be considered as a better absorber than the carbon composite in a frequency range from 12 to 18 GHz at Ku band.Originality/valueThis paper shows how cotton, which is a natural and easily supplied low-cost raw material, can be evaluated as a RAM.

Optimisation of the lateral buckling strength of corrugated composite material plate by neural networks method

Enhancing the buckling strength of laminated composite materials can be achieved in numerous ways. One method involves corrugating the laminated composite material in one direction. Corrugation provides good buckling strength in the direction perpendicular to the corrugation but a low buckling strength in the same direction as the corrugation. This investigation used composite materials strips implanted in the direction of the laminate’s corrugation to modify the ability to buckle without excessive weight on the laminate. Finite elements were applied to analyse the problem. In addition, to overcome the extensive computational requirements, a neural network (NN) system was utilised to model the study case and then optimise the structure. The NN was trained by the results of the finite elements. The parameters examined and their effects on buckling strength include the number of strips, number of layers of strips and dimension of strips. Results confirmed that the technique of strengthening the laminate using strips in the direction of corrugation waves is beneficial for increasing the critical buckling load. Specifically, the optimisation result presented an increase of 52 times in the buckling load strength versus approximately twice the increase in the mass of the plate. Using the NN to simulate and optimise the structure is a powerful approach that consumes less time than employing the finite element method.

Design of resonant structures in resin matrix to mitigate the blast wave with a very wide frequency range

In this work, resonant structures (RSs) are embedded in the resin matrix to form the micro-scale artificial composite materials to mitigate the blast wave with a very wide frequency range (BWR). The propagation of stress waves in the resin and composite materials is described, and the composite materials exhibit stronger blast wave attenuation characteristic compared with the pure resin material. The attenuation mechanism of the composite materials is explained in detail through the absorption, storage and conversion of impact energy. In addition, the influences of materials of the RSs on the performances of the composite materials are analyzed, and the RS is redesigned to further improve the attenuation effect of the composite material. Equivalent model of the composite material is first proposed and established based on the weakly nonlinear lattice system (WNLS). At the same time, artificial tree algorithm is applied to design its spring stiffness parameters. Based on the WNLS, a three-dimensional composite material plate structure is built to mitigate the overpressure of blast wave at the macro-scale. Compared with traditional materials, the composite material exhibits superior attenuation effect and greater lightweight.