Advanced Composite Materials Research Articles

Smart and responsive nano copper oxide–PDMS composite for “three-in-one” synergistic adsorptive–oxidative / reductive degradation of the persistence of organic pollutants, elimination of nanoparticles and heavy metal ion

Copper-and silica-based materials have been used globally as environmental catalysts and adsorbents for centuries. Despite their differences in their properties and roles in the participation of environmental activity, both have been combined to create various types of functional materials, ranging from copper oxides and polydimethylsiloxane (PDMS) sponge (PS) cores to advanced hybrid composite materials. In this work, CuO was incorporated onto SiO2 (CPC) by calcination of PDMS-Cu2O sponge, and the physicochemical properties and application of CPC were investigated. The CPC was homogeneous in a surface area (326.69 m2g-1), pore size (33.16 Å), pore volume (0.056 cm³g−1), and particle size (183.66 Å). This CPC has been used for the degradation (oxidation/reduction) and adsorption of azithromycin (AZM), 1,4-dichlorobenzene (DCB), rhodamine B (RB), methylene blue (MB), 4-nitrophenol (4-NP), gold nanoparticles (AuNPs), and chromium (VI). Efficiencies of CPC for the above persistence of organic pollutants (POPs) and adsorption of AuNPs and Cr(VI) were ∼72–100% under optimized conditions. CPC followed the pseudo-second-order (PSO) degradation kinetics with a higher r2 (>0.99) with eight cycles of reusability. Moreover, this synthetic strategy can be tailored to produce nanostructured composite materials and/or those associated with other species for diverse environmental and industrial applications.

Exploratory Study on the Application of Graphene Platelet-Reinforced Composite to Wind Turbine Blade.

With the growth of the wind energy market and the increase in the size of wind turbines, the demand for advanced composite materials with high strength and low density for wind turbine blades has become imperative. Graphene platelets (GPLs) stand out as highly premising reinforcements due to their exceptional physical properties, resulting in their widespread adoption in the composite industry in recent years. The present study aims to analyze the applicability of a graphene-platelet-reinforced composite (GPLRC) to wind turbine blades in terms of structural performance. A finite element blade model is constructed by referring to the National Renewable Energy Laboratory (NREL) 5 MW wind turbine, and its reliability is verified through a convergence test. The performance of the wind turbine blade is quantitatively examined in terms of the deflection and stress, natural frequencies, and twist angle. The applicability of the GPL-reinforced wind blade is explored through a comparison with wind blades manufactured with glass fiber and carbon nanotubes (CNTs). The comparison indicates that the performance of a wind blade can be remarkably improved by reinforcing with GPLs instead of traditional fillers, and the weight of not only the wind blade itself but also the wind turbine system can be remarkably reduced. The present results can be useful in the development of next-generation high-strength lightweight wind turbine blades.

Novel computational model for the failure analysis of composite pipes under bending

This study presents a novel computational model to investigate the bending behaviour of thin- and thick-walled composite pipes made from fully bonded fibre-reinforced thermoplastic composite materials. The primary objective is to analyse the stress state and predict potential failure modes of these pipes, which have gained significant interest in the oil and gas industry due to their advantageous properties. The developed model is validated through comparisons with finite element analysis and published results, demonstrating its accuracy and adaptability. Utilising the validated computational model, safety zones for composite pipes with various stacking sequences are established, providing valuable insights into the optimal design of composite pipes under bending loads. Furthermore, the method is employed to determine the maximum bending moment and critical bendable radius of the pipe, revealing the direct correlation between maximum bending moment and bending stiffness, independent of the bending radius. The findings of this study offer practical guidance for the design and optimisation of composite pipes in the oil and gas industry, promoting their adoption as a viable alternative to traditional metal pipes. The developed computational model serves as an efficient and reliable tool for engineers to make informed decisions in the design and selection of advanced composite materials for pipe applications, enabling the optimisation of pipe performance under various bending load scenarios.

On the measurement of the aerodynamic features of composite structures under subsonic airflow using mathematical modeling and machine learning method

This study investigates the aerodynamic features of functionally graded triply periodic minimal surface (FG-TPMS) structures under subsonic airflow using a combination of mathematical modeling and machine learning methods. The modified supersonic piston theory of Krumhaar is used to quantify the aerodynamic stiffness and damping matrices. Using characteristics and six distinct patterns of volume distribution of FG-TPMS materials in terms of their mechanical qualities, Hamilton’s principle, and parabolic shear deformation theory are used to extract the governing equations of the presented composite structure. After that, the differential quadrature method at the discrete places and Lagrange interpolated polynomials and Kronecker product are used to solve the governing equations in the numerical domain. This study highlights the potential of integrating advanced computational techniques with machine learning to address complex engineering problems. The findings provide valuable insights into the aerodynamic optimization of sandwich structures, paving the way for their more efficient and effective design in aerospace engineering. As an important outcome for related industries, the displacement field along with the Z direction increases by increasing the angle of airflow by approximately 9 % while this value for the X, and Y directions are 7 %, and 6 %, respectively. The proposed methodology offers a powerful tool for engineers and researchers seeking to optimize the performance of advanced composite materials under subsonic airflow conditions.

Effects of Graphene Reinforcement on Static Bending, Free Vibration, and Torsion of Wind Turbine Blades.

Renewable energy markets, particularly wind energy, have experienced remarkable growth, predominantly driven by the urgent need for decarbonization in the face of accelerating global warming. As the wind energy sector expands and turbines increase in size, there is a growing demand for advanced composite materials that offer both high strength and low density. Among these materials, graphene stands out for its excellent mechanical properties and low density. Incorporating graphene reinforcement into wind turbine blades has the potential to enhance generation efficiency and reduce the construction costs of foundation structures. As a pilot study of graphene reinforcement on wind turbine blades, this study aims to investigate the variations of mechanical characteristics and weights between traditional fiberglass-based blades and those reinforced with graphene platelets (GPLs). A finite element model of the SNL 61.5 m horizontal wind turbine blade is used and validated by comparing the analysis results with those presented in the existing literature. Case studies are conducted to explore the effects of graphene reinforcement on wind turbine blades in terms of mechanical characteristics, such as free vibration, bending, and torsional deformation. Furthermore, the masses and fabrication costs are compared among fiberglass, CNTRC, and GPLRC-based wind turbine blades. Finally, the results obtained from this study demonstrate the effectiveness of graphene reinforcement on wind turbine blades in terms of both their mechanical performance and weight reduction.

Multi-objective parametric optimization process of hybrid reinforced titanium metal matrix composite through Taguchi-Grey relation analysis (TGRA)

Hybrid titanium metal matrix composites (HTMMCs) are advanced composite materials that can be tailored to a variety of applications. Because of their decreased fuel consumption and cost, they are popular in the transportation industry. Using multi-objective optimization and Taguchi-based Grey relational analysis (TGRA), this study investigates the impact of hybrid reinforced HTMMCs synthesized using powder metallurgy on their physic mechanical properties. The research investigates reinforcements such as B4C, SiC, ZrO2, and MoS2 at various compaction pressures, milling durations, and sintering temperatures. The best powder metallurgy control parameters for HTMMC synthesis, with a milling time of 5 h, a compaction pressure of 40 MPa, a sintering temperature of 1200 °C, and a sintering time of 1 h, and a compaction time of 40 min. According to validation results, HTMMC material with optimized process parameters had experimental densities, porosities, hardness, compressive strength, and wear rates of 4.29 gm/cm3, 0.1178%, 71.53RHN, 2782.36 MPa, and 0.1519 mm3 correspondingly. The material hardness was increased by 1.99% and compressive strength by 2.87%. The use of Taguchi and GRA techniques strongly verified that the impact of milling duration and sintering temperature was the greatest of all five factors. The novel synthesized hybrid reinforcing HTMMCs outperformed pure Ti grade 5 and single and double fortified HTMMCs in terms of physic mechanical characteristics. As a result, the newly developed tetra hybrid reinforced HTMMC material is expected to be used in heavy-duty vehicles, aerospace, automobiles, maritime, and other industries.

Introducing a computer simulation to model flexural vibrations of sandwich structures reinforced by advanced nanocomposites surrounded by auxetic concrete foundation

This study introduces a computer simulation framework aimed at analyzing the flexural vibrations of sandwich structures comprising a polymer core sandwiched between two face sheets reinforced with graphene oxide powder (GOP) nanocomposites. The sandwich structures are situated on an auxetic concrete foundation, incorporating sophisticated theoretical formulations to approximate the three-dimensional displacement fields of GOP-reinforced rectangular plates under varying loading conditions. The research addresses the complex interplay of material properties and geometric configurations, crucial for optimizing the structural performance of advanced composite materials in practical applications. The computational model integrates analytical techniques to predict the dynamic behavior of the sandwich structure’s flexural vibrations. Key parameters such as the dispersion of GOP within the polymer matrix, and the auxetic properties of the concrete foundation are systematically varied and analyzed to understand their impact on the overall structural response. Results from the simulations provide insights into the natural frequencies of the GOP-reinforced sandwich structures, offering valuable data for design engineers and materials scientists. The study underscores the potential of graphene oxide powder nanocomposites in enhancing the mechanical performance of sandwich structures, particularly when supported by innovative foundation materials like auxetic concrete. Future research directions include validation and further refinement of the computational model to accommodate additional complexities and real-world conditions.

Investigation on Mechanical Properties of Agro and Industrial Waste Reinforcement in Aluminium 7075 Composite with Liquid Metal Stir Casting Route

Day-to-day life advanced composite materials usage is increasing continuously and replacing the existing monolithic materials. These composite materials are designed and fabricated for human needs with specific applications and also meet the standard requirements. In present study, the agro and industrial wastes derived ceramic reinforcements based Aluminium metal matrix composites, i.e. AA7075/welding slag and AA7075/Rice husk ash are fabricated through liquid metal stir casting route with varying the reinforcement contents from 2 to 12 (wt.%) in the matrix. Mechanical and microstructural characterization of the AA 7075 metal matrix composite were measured and compared to the base material. The results show an improved mechanical strength and high hardness in composites. Impact energy has also significantly improved at higher concentrations of reinforcement particles. Impact energy of the composites increases to 3 J for 9% and 12%, the maximum tensile strength obtained is 173 MPa for 12% Weld Slag MMC. The highest hardness achieved is 98 BHN for 12% Weld Slag MMC. Furthermore, the microstructural results reflect significant grain refinement with stir casting process with good interface characteristics in the matrix and uniform dispersion of agro reinforcement’s particles.

Bending, free vibration and buckling finite element analysis of porous functionally graded plates with various porosity distributions using an improved FSDT

Functionally graded materials (FGMs) are advanced composite materials with spatially varying properties, and their porosity distribution further enhances their complexity. The distribution pattern of porosity within a porous material plays a crucial role in determining the mechanical response of these structures. Therefore, the main objective of this study is to analyze the bending, free vibration, and buckling characteristics of porous FG plates by considering different porosity distributions and their effects on the overall behavior. To achieve this goal, a new finite element model is developed in the framework of an improved first-order shear deformation theory (IFSDT). In contrast to the conventional Mindlin–Reissner theory, the present IFSDT incorporates an improved mathematical formulation and provides a more realistic parabolic depiction of shear strain throughout the plate’s thickness without using any shear correction factors. In the present study, five types of porosity distribution functions are considered for the analysis. The material characteristics of the FGM porous plate change gradually in the thickness direction based on a power-law function. The governing equations are derived here using Hamilton’s principle, and a finite element method is employed for numerical analysis. Comparative analyses with previously published literature underscore the precision and simplicity of our developed finite element model. Moreover, the effects of various types of loads, porosity parameters, power-law index, side-to-thickness ratio, aspect ratio, porosity distributions and boundary conditions on the deflections, natural frequencies, and critical buckling loads are thoroughly analyzed in detail. Finally, the findings of this research contribute to the understanding of the mechanical behavior of FGMs and pave the way for designing and optimizing novel porous functionally graded structures.

Frontal Polymerization for the Rapid Obtainment of Polymer Composites.

Among the different polymerization techniques, frontal polymerization (FP) has gained high interest from the scientific community because of its peculiar characteristics: in particular, compared to classic polymerization reactions, FP allows for a better exploitation of the heat of polymerization involved, without requiring any external energy input apart from an initial photo or thermal ignition that triggers the reaction. The latter usually propagates in a few tenths of seconds or (at most) minutes through a hot self-sustaining polymerization front, giving rise to the formation of fully cured thermosetting networks or thermoplastic polymers. Furthermore, different polymerization mechanisms can be involved in FP reactions, comprising cationic or anionic, ring-opening metathesis, and free-radical polymerization, among others. Further, it is possible to run FP reactions in bulk, in solution, or even using solid monomers if they are melted at the temperature of the front, notwithstanding the possibility of using reactive systems containing fillers or fiber/fabric reinforcements. In this context, the use of FP is becoming very important also for the design and production of advanced (nano)composite materials, saving processing time and achieving the completeness of the curing reaction, even in the presence of high filler/reinforcement loadings. Therefore, this mini-review aims to provide the reader with the basics of FP and its main peculiarities, even in the context of preparing high-performing composites. In this respect, some recent case studies witnessing the potentialities of frontal polymerization for the design of advanced (nano)composite systems will be elucidated. Finally, some perspectives about possible future developments will be proposed.

Low-flammability carbon fiber reinforced composites based on low-viscosity phosphorus-containing epoxy binders for transfer molding methods

This study is the first investigation into the possibility of low viscosity phosphorus-containing epoxy binders using triglycidyl phosphate for carbon fiber-reinforced polymers (CFRPs) production by resin transfer molding (RTM). Rheological studies and flammability evaluations were carried out to determine the optimum concentrations of triglycidyl phosphate in the epoxy binder. The introduction of triglycidyl phosphate into the epoxy composition was shown to produce self-extinguishing epoxy polymers. In addition, the curing kinetics of the phosphorus-containing epoxy binder was evaluated using differential scanning calorimetry (DSC) to optimize the curing process. The impregnation process of the product in the PAM-RTM software package was modeled to evaluate the possibility of obtaining large-size CFRP parts based on the developed binder by transfer molding methods. The physical-mechanical and fire-resistant tests of CFRPs showed significant improvement in flame-retardant properties in the modified samples, while maintaining high values of strength and elastic modulus. The study concluded that the introduced triglycidyl phosphate significantly affects the binder properties by reducing the viscosity, and increasing the flame retardancy, thus opening a promising direction for developing advanced composite materials.

Improved interfacial adhesion of carbon fiber‐reinforced polydicyclopentadiene layered composite material by modification of norbornene derivatives

AbstractSurface chemical grafting modifications of carbon fibers (CFs) using 5‐(triethoxysilyl)norbornene (TOS), norbornene carboxylic acid tert‐butyl ester (NB‐TBE), and 5‐norbornene‐2,3‐dicarboxylic anhydride (NA) improved interfacial interactions between CFs and poly(dicyclopentadiene) (PDCPD) resin. The ring‐opening metathesis polymerization (ROMP) of DCPD, catalyzed by Grubbs catalyst II, enabled the fabrication of PDCPD/CF layered composite materials with resin and fibers tightly adhered. The optimal composite exhibited remarkable mechanical properties, with a tensile strength of 654.6 MPa and flexural strength of 510.7 MPa. Excellent thermal stability with a maximum weight loss rate in temperatures above 450°C and good chemical resistance with a weight change of about 1% in both acidic and alkaline media highlight the promising potential of these materials for use in harsh environments. The simple yet efficient approach of TOS, NB‐TBE, and NA‐enhanced layered CF shows great promise as advanced composite materials for industrial applications.Highlights Norbornene derivatives such as TOS, NB‐TBE, and NA are suitable modifiers for CF. ROMP of DCPD and norbornene group onto CFs, fabrication of PDCPD/CF composite materials. The composite exhibited remarkable interfacial adhesion and mechanical properties.

Non-geodesic winding design method for the composite shell of unequal-pole-hole solid rocket motor

Advanced composite materials have the advantages of high specific strength, high specific modulus, good fatigue resistance, good shock absorption performance, and strong designability. They are widely used in the fields of national defense science and technology and civil engineering. To make a more accurate winding design of the composite shell of the non-equidistant solid rocket motor, based on the ANSYS ACP composite structure design and analysis software, this paper uses the cubic spline function method to design the fiber winding thickness of the shell head section for a solid rocket motor. The Runge-Kutta method is used to calculate the changing winding angle of the non-geodesic line, and the changing winding angle and winding thickness on the head are simulated based on the look-up table interpolation table module in ACP. Finally, the mechanical properties of the designed shell under certain internal pressure are simulated and analyzed. Through the simulation analysis of the designed engine model, it is found that the connection between the front head and the barrel section is a weak profit, and the follow-up study should reinforce this area.

An Analytical Analysis of the Hydrostatic Bending to Design a Wastewater Treatment Plant by a New Advanced Composite Material

An Analytical Analysis of the Hydrostatic Bending to Design a Wastewater Treatment Plant by a New Advanced Composite Material

Facile fabrication of multifunctional aramid fibers for excellent UV resistance in extreme environments

Aramid fibers (AFs) are widely applied as structural material, cordage, and versatile protection in many harsh environments, including space and deep sea. However, intense ultraviolet (UV)/ irradiation, high/low temperatures, and/or chemical solvent with strong acid/alkali/corrosion feature seriously affect their mechanical properties, thus severely shorten the life cycle of AF-based products. Inspiration by the principle of multiple refractions and partly reflections, an innovative strategy by depositing of laminated Al2O3/TiO2 composite onto the surface of poly(m-phenylene isophthalamide) (PMIA) via atomic layer deposition (ALD) technique was presented. The tenacity of ALD-coated PMIA only decreases by ∼ 8 %, and the yellowness index (YI) only increasing to 129.24 %, far lower than 321.63 % of pristine PMIA fabric under the combination of intense UV irradiation (4260 W/m2) and high temperature (200 °C + ) for 6 h, which equals to continuous strong sunlight exposure for approximately 7.5 years. Meanwhile, ultraviolet protection factor (UPF) value increased to 126.4, which is double that of the pristine PMIA fabric, exhibiting an impressive UV-resistance property. Furthermore, the ALD-coated PMIAs also shows a significant enhancement in both chemical and thermal stabilities. In all, this work not only forge a new route for the functionalization of fibrous materials, but also exhibits great promise for next generation advanced composite material and cutting-edge equipment in harsh environment.

The Effect of Load Steps and Initial Crack Length on Stress Distribution of Fiber Metal Laminates

Fiber Metal Laminates (FMLs) are advanced composite materials composed of alternating layers of fiber-reinforced composites and metal sheets, offering a unique blend of high strength, stiffness, and fatigue resistance. Understanding the behavior of FMLs under different loading conditions, particularly in the presence of initial cracks, is crucial for predicting their structural integrity and performance. This study investigates the effect of initial crack length and load steps on the stress distribution within FML structures through numerical simulation. A glass fiber-reinforced epoxy (GFRE) composite is constituted by glass fibers in off-axis directions of 0o/90o. The crack length of 3 mm, 6 mm, 9 mm, and 12 mm is initially defined on the side of fiber metal laminates. The tensile load was gradually applied to the laminates for five different ratios. The ratios are defined by dividing the tensile load with the area of the laminates which is then called stress ratio. The results show that the greater the initial crack length and load step ratio, the greater the stress around the crack tip. The stress distribution in each layer of the laminates shows different characteristics between tensile and compressive. This will affect the crack propagation behavior of the laminates. Moreover, the findings also provide valuable insights for optimizing FML design, improving damage tolerance, and extending service life in diverse engineering applications.

Exploring dielectric properties and polarization relaxation processes in ionic liquid crystals with synthesized carbon and gold nanoparticles

The main goal is to study the structural and dielectric characteristics of advanced composite materials based on ionic metal alkanoates with various types of nanoparticles. The matrix Cd+2(C7H15COO)−2 formed as a result of the reaction of cadmium with the carboxylate groups of alkanoate (C7H15COO)−2 is used for the synthesis of nanoparticles. At room temperature, the matrix of the ionic crystalline material represents multilayer structure with each layer thickness of 1.8 nm. However, when heated in the temperature range from 100 °C to 180 °C, the matrix undergoes a phase transition into the liquid crystalline smectic A phase, preserved after cooling to room temperature. This transition opens up possibilities for the synthesis of carbon and gold nanoparticles. The temperature treatments of the matrix allow to control of the size and shape of nanoparticles during synthesis and create highly stable nanocomposites. The structural features and dielectric properties of these nanocomposites are studied using transmission electron microscopy, enabling to determine of the sizes of nanoparticles and their dispersion and impedance spectroscopy, respectively. Dielectric properties of nanocomposite materials were studied at different temperatures corresponding to two material phases. We carried out an analysis of the dielectric characteristics of the pure matrix in comparison with nanocomposite materials, containing carbon and gold nanoparticles to identify the role of the nanoparticles. Based on our experimental data, we proposed a model to explain the charge transfer process, taking into account relaxation processes and polarization of nanocomposite materials.

Optimal Molecular Dynamics System Size for Increased Precision and Efficiency for Epoxy Materials.

Molecular dynamics (MD) simulation is an important tool for predicting thermo-mechanical properties of polymer resins at the nanometer length scale, which is particularly important for efficient computationally driven design of advanced composite materials and structures. Because of the statistical nature of modeling amorphous materials on the nanometer length scale, multiple MD models (replicates) are typically built and simulated for statistical sampling of predicted properties. Larger replicates generally provide higher precision in the predictions but result in higher simulation times. Unfortunately, there is insufficient information in the literature to establish guidelines between MD model size and the resulting precision in predicted thermo-mechanical properties. The objective of this study was to determine the optimal MD model size of epoxy resin to balance efficiency and precision. The results show that an MD model size of 15,000 atoms provides for the fastest simulations without sacrificing precision in the prediction of mass density, elastic properties, strength, and thermal properties of epoxy. The results of this study are important for efficient computational process modeling and integrated computational materials engineering (ICME) for the design of next-generation composite materials for demanding applications.

Inverse Differential Quadrature Based Model for Static Behaviour of Variable Stiffness Curved Composite Beams

Recent advancements in fibre placement technologies have expanded the potential applications of variable stiffness curved composite beams in industries such as aerospace, automotive, and naval engineering. Accurate solution techniques for examining these beams, especially those composed of advanced composite materials, are indispensable. In view of this demand, this study proposes a new high-order computational tool that combines the higher-order accuracy of the emerging inverse differential quadrature method (iDQM) and the simple kinematics of the Timoshenko beam theory for efficient and accurate prediction of the static behaviour of both constant stiffness and variable stiffness curved beam structures. This novel application of iDQM to curved beam analysis is leveraged upon its excellent potential to mitigate differentiation-induced errors by using the so-called indirect approximation strategy. Simple procedures for implementing different orders of iDQM models are presented to analyse curved beam problems, and are independently benchmarked against closed-form Navier's solutions, as well as numerical solutions obtained through the differential quadrature method (DQM) and finite element method (FEM), demonstrating excellent spectral accuracy. Furthermore, the iDQM scheme offers outstanding potential in recovering transverse shear stress, achieving superior accuracy over lower-order FEM in approximating higher-order derivatives. Remarkably, iDQM predictions for variable stiffness curved beams exhibit satisfactory agreement with the Strong Unified Formulation, achieving over 98% computational efficiency. Finally, convergence analysis of iDQM solutions reveal up to three orders of improved accuracy and faster convergence rates compared to the DQM, constituting a new benchmark for curved beam analysis.

Advanced composite material for high-performance supercapacitors: integrating graphene oxide and barium chromate

Graphene oxide-based Barium chromate (BaCr2O4@GO) composites were successfully synthesized through sonication assisted by a hydrothermal process designed for supercapacitor applications. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and morphological analyses were employed to characterize the nanostructured composites. The XRD and FTIR results reveal that the GO nanoparticles are arranged in a honeycomb-like configuration. Moreover, the TEM images reveal the presence of cauliflower-like structures in the morphology of the composites, which is attributed to the effective intercalation of GO during the thermal reduction process. The electrochemical properties of the nanocomposite were compared to those reported in previous studies on metal chromite materials aimed at enhancing supercapacity applications. The analysis of Galvanostatic Charge–Discharge (GCD) data indicates a significant increase in power density values from 292 W kg−1 to 495.5 W kg−1 for the Nanocomposites. The ability to achieve a balance between enhanced power density and efficient ion transport positions the -nanocomposites as a valuable candidate for advancing the performance of supercapacitors.