Fraction Of Carbon Nanotubes Research Articles

The role of agglomeration in the physical properties of CNTs/polymer nanocomposites: A literature review

The physical properties of nanocomposites may be improved by addition of low content of carbon nanotubes (CNTs). In contrast, for higher concentrations of CNTs, the physical properties of nanocomposites may be degraded owing to agglomeration. In recent years, due to the increasing applications of CNTs, many efforts have been performed to overcome the agglomerates, achieving the real potential of CNTs in improving the performance of nanocomposites. To this end, in this review paper, the impact of agglomeration on various physical properties of CNTs/polymer nanocomposites was investigated. Besides, the present work provides a review of the effective factors that lead to the CNTs agglomeration. The conventional and novel strategies adopted to control this phenomenon are also presented. The findings revealed that dense agglomerates negatively affect all physical properties of nanocomposites. It was observed that the elastic modulus and tensile strength of epoxy-based nanocomposites can be degraded around 25 and 35% when the weight fraction of CNTs is increased from 0.5 to 1.0 wt.%. Besides, in the case of fracture toughness, it was reported that by adding 0.1, 0.2, 0.3 and 0.4 wt.% of CNTs to an epoxy-based nanocomposites, the fracture toughness enhances around 17, 24, 30, and 4%, respectively. In addition, a 50% reduction in the thermal conductivity of the nanocomposite may be happened due to the formation of CNTs agglomeration. It was also concluded that in the presence of agglomerates, the coefficient of friction of a polymer-based nanocomposites can increases from 0.027 to 0.034. In contrast, slight agglomerates may improve electrical properties to a certain extent. It was also concluded some of the expensive strategies proposed to overcome the agglomeration may adversely affect the CNTs structure, may not be so effective to prevent the occurrence of agglomeration, or may not be applicable in high-volume production of nanocomposites. However, the implementation of novel strategies such as 3D porous structures could overcome this challenge significantly.

Free Vibrations and Flutter Analysis of Composite Plates Reinforced with Carbon Nanotubes

This paper considers the free vibration and flutter of carbon nanotube (CNT) reinforced nanocomposite plates subjected to supersonic flow. From the literature review, a great deal of research has been conducted on the free vibration and flutter response of high-volume CNT/nanocomposite structures; however, there is little research on the flutter instability of low-volume CNT/nanocomposite structures. In this study, free vibration and flutter analysis of classical CNT/nanocomposite thin plates with aligned and uniformly distributed reinforcement and low CNT volume fraction are performed. The geometry of the CNTs and the definition of the nanocomposite material properties are considered. The nanocomposite properties are estimated based on micromechanical modeling, while the governing relations of the nanocomposite plates are derived according to Kirchhoff’s plate theory with von Karman nonlinear strains. Identification of vibrational modes for nanocomposite thin plates and analytical/graphical evaluation of flutter are presented. The novel contribution of this work is the analysis of the eigenfrequencies and dynamic instabilities of nanocomposite plates with a low fraction of CNTs aligned and uniformly distributed in the polymer matrix. This article is helpful for a comprehensive understanding of the influence of a low-volume fraction and uniform distribution of CNTs and boundary conditions on the dynamic instabilities of nanocomposite plates.

Carbon nanotube-doped Ag[formula omitted]O ink: A cost-effective method for strengthening inkjet-printed flexible circuits

Silver ink demonstrates significant potential in the field of printed electronics due to its excellent electrical conductivity and stability. However, traditional silver electrodes still face issues such as microscopic fractures under mechanical stresses like bending, twisting, and stretching, which are common in conformal circuits and flexible electronic devices. This study introduces a cost-effective, one-step method for synthesizing high stability carbon nanotube (CNT)-doped Ag2O ink. The feasibility of using CNTs as a scaffold with silver as the conductive network is validated. The study investigated the microscopic structural characteristics and composition of the printed films. It also analyzed their electrical conductivity and mechanical properties before and after annealing. A special surfactant ratio was employed to ensure the ink remains stable for an extended period of time. In testing, CNT-doped silver films exhibit exceptional electrical conductivity, and the printed lines achieve extremely low resistance after low-temperature (200 °C) annealing. The ink with a 5.45% mass fraction of CNTs achieved a minimum resistivity of approximately 1.4×10−7Ωm. Under external twisting forces, CNTs enhance the yield strength of the conductors by transferring and absorbing stress, refining the grain structure within the conductive network, and increasing the dislocation density. The printed circuits maintained nearly the initial resistivity even after multiple twists. The CNT-doped Ag2O ink demonstrates outstanding mechanical strength and flexibility, showcasing its potential for practical applications.

Enhanced Mechanical and Multifunctional Properties of GNPs/CNTs Hybridized PLA Nanocomposites by Implementing Dual‐Processing of Pickering Emulsion‐Melt Blending Methods

AbstractPolylactic acid (PLA) composites with multifunctional properties and minimal filler content are increasingly in demand across various industries. However, achieving a balance between high mechanical strength, electrical conductivity, thermal conductivity, and electromagnetic interference (EMI) shielding remains challenging. In this study, a dual‐processing strategy combining Pickering emulsion templating and melt blending is presented to hybridize 1D carbon nanotubes (CNTs) and 2D graphene nanoplatelets (GNPs) within a PLA matrix. This approach successfully forms a stable dual‐filler network, ensuring uniform dispersion of the fillers. The results show that this method significantly enhances the performance of the resulting PM‐PGxCy composites (P: Pickering emulsion; M: melt blending; x and y: mass fractions of GNPs and CNTs, respectively). Specifically, the PM‐PG1.43C1.43 composite exhibits remarkable improvements in mechanical strength (56.2 MPa), electrical conductivity (43.5 S m−1), EMI shielding effectiveness (20.1 dB), and thermal conductivity (0.34 W m·K−1), outperforming composites prepared using either method alone. These findings indicate that the dual‐processing strategy effectively combines 1D and 2D fillers, facilitating superior interfacial interactions and enhancing the multifunctional properties of PLA‐based composites. This study offers a new approach to achieving high‐performance PLA composites with low filler content, offering significant potential for applications in electronics, packaging, and EMI shielding technologies.

Improved micromechanics model for piezoresistive polymethyl methacrylate modified with carbon nanotubes: considering the effect of mineral fillers

ABSTRACT Polymethyl methacrylate (PMMA) modified with carbon nanotubes (CNTs) shows promise as a piezoresistive material for road pavements. The micromechanics model holds significance in designing and optimising the piezoresistive performance of CNTs-modified PMMA. In this paper, the excluded volume is introduced to characterise the effect of mineral fillers, as the main components in PMMA mastic, within the micromechanics model. The investigation integrates Scanning Electron Microscopy (SEM), Monte Carlo numerical simulation, and electrical conductivity tests. Subsequently, a parameter analysis is conducted to optimise the piezoresistive sensitivity. SEM results reveal two representative interphase morphologies and identify the excluded volume of mineral fillers. It is estimated as 19.4% of the solid volume of mineral fillers through the numerical simulation. Moreover, the modelled electrical conductivity of PMMA mastic using the improved model precisely aligns with experimental results. These could validate and quantify the excluded volume of mineral fillers and then improve the micromechanics model for piezoresistivity. The parameter analysis demonstrates that mineral fillers markedly enhance the piezoresistive sensitivity of PMMA mastic. It is suggested to prepare PMMA mastic with a lower Poisson’s ratio and volume fraction of CNTs. This improved micromechanics model could guide the design and optimisation of piezoresistive polymers in intelligent road systems.

Molecular Dynamics Simulation and Experimental Study of Friction and Wear Characteristics of Carbon Nanotube-Reinforced Nitrile Butadiene Rubber

Nitrile butadiene rubber (NBR) and its various composite materials are widely employed as friction materials in mechanical equipment. The use of carbon nanotube (CNT) reinforcement in NBR for improved friction and wear characteristics has become a major research focus. However, the mechanisms underlying the improvement in the friction and wear characteristics of NBR with different CNT contents remain insufficiently elucidated. Therefore, we conducted a combined analysis of NBR reinforced with varying CNT contents through molecular dynamics (MD) simulations and ring–block friction experiments. The aim is to analyze the extent to which CNTs enhance the water-lubricated friction and dry wear properties of NBR and explore the improvement mechanisms through molecular chain characteristics. The results of this study demonstrate that as the mass fraction of CNTs (0%, 1.25%, 2.5%, 5%) increases, the water-lubricated friction coefficient of NBR continuously decreases. Under water-lubricated conditions, CNTs improve the water storage capacity of the NBR surface and enhance lubrication efficiency. In the dry wear state, CNTs help reduce scratch depth and dry wear volume.

The effect of CNT grafting on the mechanical properties of the UHMWPE fiber/HDPE composite

In order to improve the mechanical properties of the ultra‐high molecular weight polyethylene (UHMWPE) fiber‐reinforced high‐density polyethylene (HDPE) composite, carbon nanotube (CNT) was grafted on the UHMWPE fiber. The UHMWPE fiber/HDPE composite was prepared by injection molding process, and the effects of CNT contents on the mechanical properties of composite materials were studied. The results show that the mass fraction of CNT will significantly affect the mechanical properties of the composite. When the CNT content is 4 wt%, the tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength of the UHMWPE fiber/treated CNT/HDPE composite increased compared to the UHMWPE fiber/CNT/HDPE composite and UHMWPE fiber/HDPE composite. When the CNT content is 4 wt%, the above‐mentioned performance is the best. Pull‐out and fracture, bridging effect, and crack deflection effect are the main mechanisms of CNTs in UHMWPE fiber/HDPE composites. This study provides new insights into the interface design of UHMWPE fiber/HDPE composites and paves the way for their further development.

Effect of carbon nanotubes on mechanical properties of aluminum matrix composites: A review

Abstract Carbon nanotubes (CNTs) are renowned for their low density, high elastic modulus, and exceptional electrical and thermal properties. The continuously developing applications of CNTs provide higher specific stiffness and strength for composite materials. The unique characteristics of CNTs make them ideal reinforcing particles in aluminum matrix composites (AMMCs), which generally exhibit excellent mechanical properties. CNTs/AMMCs are usually prepared using methods such as powder metallurgy, casting, spray deposition, and reactive melting. The uniform diffusion of CNTs in composites is crucial for enhancing the properties of CNTs/AMMCs. The properties of CNTs/AMMCs largely depend on the content, morphology, and distribution of reinforcements in the matrix and the interaction between reinforcements and the matrix. By adding an appropriate volume fraction of CNTs, the hardness, tensile strength, compressive strength, and electrical properties of CNTs/AMMCs were significantly improved. The effects of CNT content on the mechanical properties of CNTs/AMMCs, including the tensile strength, yield strength, compressive strength, stress–strain curve behavior, elastic modulus, hardness, creep, and fatigue behavior, were revealed. The design of microstructure, optimization of the preparation process, and optimization of composition can further improve the mechanical properties of CNTs/AMMCs and expand their application in engineering. The design concept of integrating material homogenization and functional unit structure through biomimetic design of novel gradient structures, layered structures, and multi-level twin structures further optimizes the composition and microstructure of CNTs/AMMCs, which is the key to further obtaining high-performance CNTs/AMMCs. As a multifunctional composite material, CNTs/AMMCs have broad application prospects in fields such as air force, military, aerospace, automation, and electronics. Moreover, CNTs/AMMCs have potential applications in cell therapy, tissue engineering, and other areas.

Experimental free vibration and tensile test results of a five-layer sandwich plate by comparing various carbon nanostructure reinforcements with SMA

Considering to need for the sensitive and destructive industries for high stiffness and low weight, an experimental free vibration and tensile test results of a five-layer sandwich plate by comparing various carbon nano structures reinforcements with SMA is discussed. The effect of various reinforcements, including carbon nanostructures (carbon nanotubes (CNT), carbon nanorods (CNRs), Graphene platelets (GPLs)) and nitinol shape memory alloy (SMA) wire on the vibration behavior of a five-layer sandwich plate with a foam core is investigated. The purpose and novelty of this work are to compare the effect of different reinforcements on the vibrations of a five-layer plate so that by using this comparison, one can choose the best reinforcements according to the needs of the desired industry and more suitable economic conditions. Considering a 1 % weight fraction of epoxy resin, GPLs, CNTs, and CNRs increase Young's modulus of face sheets by 30 %, 25 %, and 5.8 %, respectively. In this work, a five-layer sandwich structure model can be suggested, and numerically analyzed. The special advantage novelty of this research compared to previous research is the construction of this five-layer model. This is a simple modeling structure for the construction and preliminary examination of structures with five layers experimentally. Also, the composite structure is made by the vacuum pump method, which does not have the disadvantages of the manual method, and the method is completely optimal. At first, the Young's and shear moduli of unidirectional glass fiber (UGF) are calculated by performing a tensile test. To examine all aspects of the construction of five-layer structures during construction, in this article first, the face sheets are made separately using resin, UGF, and various reinforcements, and then the layers of face sheets and the cores are connected using glue. In the following, the equations of motion for the sandwich plate are derived using refined first-order shear deformation theory (RFSDT) by employing Hamilton's principle. Using the Halpin-Tsai equation and the extended rule of mixture, the mechanical properties of the reinforced composite face sheets are obtained. According to the Brinson model, the constitutive equations of the SMA are presented. The influence of various parameters such as side ratio, thickness ratio, weight fraction of CNRs, CNTs, GPLs and SMA wire, fiber angle, and temperature changes on dimensionless fundamental frequency is also represented. Also, the natural frequency of orthotropic plates by considering reinforcements is higher than that without considering reinforcements. By increasing the aspect ratio (a/h), the dimensionless natural frequency increases, while the natural frequency decreases. For two-layer square angular asymmetric laminated sheets (-θ/θ), the minimum dimensionless natural frequency occurred at the fiber placement angle approximately equal to 26 and 64°. The highest frequency is related to the sandwich plate in that its face sheets have higher strength and stiffness because it is placed further from the middle plane. Also, the highest frequency is related to the sandwich plate, whose face sheets are reinforced with GPLs.

Evolution of surface oxide chemistry and its effect on the electrochemical degradation behaviour of AlCoFeCuNi high entropy alloy coating incorporated with multiwalled carbon nanotubes

AlCoFeCuNi high entropy alloy (HEA) coatings containing different volume fractions of carbon nanotubes (CNTs) were electrodeposited over mild steel substrate. Phase constitution, morphological evolution, electrochemical corrosion properties and surface oxide chemistry of the coatings were investigated as a function of their CNT content and correlated. With initial incorporation of the CNTs, the surface morphology of the composite coatings became progressively finer and compact till an optimum CNT volume fraction. Higher volume fractions of CNTs led to their agglomeration which yielded rougher and defective coating morphology. Corrosion rate of the HEA coating was highly sensitive to the CNT content and at an optimum CNT volume fraction HEA-CNT composite coatings (HEA_CNT-3 coating produced from electrolyte with 10 mg/L of CNT) with lowest corrosion rate was obtained (polarization resistance: Rp = 1178.85 Ω-cm2) while the highest corrosion rate was observed for the pristine HEA coating (Rp = 225.84 Ω-cm2). The coating with highest CNT volume fraction (HEA_CNT-6 coating produced from electrolyte with 35 mg/L of CNT) exhibited the polarization resistance value of 281.80 Ω-cm2. Contact angle measurement revealed that with increase in CNT content, coating hydrophobicity increased monotonically. Analysis of the surface oxide layer of the exposed samples exhibited increase in the relative content of Co3O4, CuO, NiO, AlO(OH) oxides with the presence of CNTs. This work shows that an optimum volume fraction of CNT which produces relatively compact morphology and facilitates evolution of stabler surface oxides leads to significant enhancement in the corrosion resistance of AlCoFeCuNi HEA-CNT composite coating.

Heat transfer analysis of MHD oscillatory SWCNT/MWCNT‐H2O hybrid nanofluid flow in a channel

AbstractRegulating the thermal conductivity of the fluid in various heat exchange systems plays an important role. In this regard, the carbon nanotubes (CNTs), with their higher thermal conductivity, can enhance the heat transfer potential. The main objective of the present study is to explore the impact of suction and injection on the oscillatory flow of CNT‐based hybrid nanofluid through a channel under the influence of the magnetic field for analysing heat transfer perspectives. While developing a mathematical model of the problem, we also considered other relevant elements, such as thermal radiation for optically thin fluids and porous mediums. The behaviour of a water‐SWCNT + MWCNT hybrid nanofluid is studied concerning the volume fraction of CNTs. The governing flow equations have been solved to obtain the correct solutions for the distribution of velocities and temperatures. Graphs and tables are used to assess the impact of relevant parameters on the flow and derived quantities. Adding CNTs to a fluid reduces its temperature and velocity, making it ideal for cooling systems. However, plates exhibit a maximum heat transfer of 35.35% and 25.35%, respectively, for and . The magnetic and constant pressure parameters greatly diminish the fluid's velocity, while the thermal buoyancy forces strengthen the flow. The effectiveness of the current study is confirmed by comparing its results to those from previous investigations.

Study on Nanomaterials Coated Natural Coir Fibers as Crack Arrestor in Cement Composite

The process of inclusion of carbon nanotubes as fibers in cement paste has been proved to have optimistic effect as it enhances the tensile property of cement paste composite. Coir fibers have exceptional mechanical qualities and are thus employed as reinforcement in cement composites. Epoxy resin, which has a high Young’s modulus, is an ideal component for bonding carbon nanotubes (CNTs) to coir fiber. This paper describes a novel kind of nanocomposite made of L-12 epoxy resin and CNTs at the nanolevel, along with coir fibers at the microlevel which operate as crack arrestors. To remove surface contaminants, coir fibers are first treated with sodium hydroxide (NaOH). Epoxy/CNTs polymer coatings were developed at varying CNTs fractions (0.05, 0.1, 0.15, and 0.2 wt.% of cement). Multiwalled CNTs were combined in distilled water, followed by epoxy resin and hardener (9 : 1 v/v) polymer in an ultrasonic sonicator for 90 min to ensure full dispersion of CNTs within the epoxy polymer. This blend is now coated on the treated clustered coir fiber (length 10 cm, 10 strands) and reinforced along the length of a cement composite beam 20 mm × 20 mm × 80 mm in size. Tensile and three-point tests were performed to evaluate the mechanical characteristics of the hybrid composite. The linear elastic finite element analysis is employed to distinguish their failure phenomena via fatigue or fracture behavior. The microstructure behavior and the effect of coating material on the coir fibers were investigated using scanning electron microscope and EDX analysis. The reinforcing impact of nanopolymer coated coir fiber in cement composite diminished the tensile and flexural strength after 0.1 wt.% of CNT fraction but increased the composite’s durability and Young’s modulus. Fourier transform infrared spectroscopy analysis was carried out to assess the chemical interaction between the epoxy/CNTs and the coir fibers. The simulation was performed using ANSYS workbench, and the modeling results were within an acceptable 10% range of the experimental data. Nevertheless, it can be concluded that the hybrid composite is capable of enhancing the composite’s stress and strain capacity by regulating the fracture propagation process at the crack’s end.

Analytical modeling of the electrical conductivity of CNT-filled polymer nanocomposites

Electrical conductivity of most polymeric insulators can be drastically enhanced by introducing a small volume fraction ( ~ 1 % ) of conductive nanofillers. These nanocomposites find wide-ranging engineering applications from cellular metamaterials to strain sensors. In this work, we present a mathematical model to predict the effective electrical conductivity of carbon nanotubes (CNTs)/polymer nanocomposites accounting for the conductivity, dimensions, volume fraction, and alignment of the CNTs. Eshelby’s classical equivalent inclusion method (EIM) is generalized to account for electron-hopping—a key mechanism of electron transport across CNTs, and is validated with experimental data. Two measurements, namely, the limit angle of filler orientation and the probability distribution function, are used to control the alignment of CNTs within the composites. Our simulations show that decreasing the angle from a uniformly random distribution to a fully aligned state significantly reduces the transverse electrical conductivity, while the longitudinal conductivity shows less sensitivity to angle variation. Moreover, it is observed that distributing CNTs with non-uniform probability distribution functions results in an increase in longitudinal conductivity and a decrease in transverse conductivity, with these differences becoming more pronounced as the volume fraction of CNTs is increased. A reduction in CNT length decreases the effective electrical conductivity due to the reduced number of available conductive pathways while reducing CNT diameter increases the conductivity.

Nonlinear bending examination of nanocomposite cylindrical shell exposed to mechanical loads using dynamic relaxation method

In the current context, the nonlinear bending examination of a carbon nanotube reinforced composite (CNTRC) shell exposed to mechanical loading using the first-order shear deformation shell model via the dynamic relaxation (DR) procedure, is perused. The composite shell is assumed to be reinforced in the longitudinal axis. The curved morphology distribution of CNTs is considered to be functionally graded (FG) or uniform along the shell thickness. Mechanical properties of the constituents are gathered based on the modified rule of the mixture. For verification, the present numeric outcomes are compared with available references and ABAQUS finite element package. Finally, the roles of effective items including carbon nanotubes (CNTs) distributions, thickness-to-radius and length-to-radius ratios, boundary conditions, and the volume fraction of CNTs are investigated on the maximum non-dimension deflection.

Analysis of low-velocity impact on FG-CNT reinforced cantilever sandwich beams: An FOSNDT approach

This study analyzes the low-velocity impact response of cantilever sandwich beams with foam cores and carbon nanotube (CNT) reinforced facesheets. Using the fifth-order shear and normal deformation theory, we explore three CNT distribution types through the thickness of the facesheets: uniformly distributed UD, functionally graded-V FG-V, and functionally graded-Λ FG-Λ. The contact force during impact is calculated according to Hertz contact law. Our findings indicate that the FG-V distribution offers the highest contact stiffness, resulting in reduced deflection compared to UD and FG-Λ distributions. Additionally, an increase in the core-to-face thickness ratio leads to decreased deflection and increased contact force, attributed to enhanced beam stiffness. The volumetric fraction of CNTs also plays a critical role, increased CNT content raises beam stiffness, decreasing deflection and enhancing contact force. Furthermore, the impactor’s initial velocity directly influences the deflection and contact force, with higher velocities leading to greater deflections due to increased kinetic energy. This comprehensive analysis underscores the significant effects of CNT distribution, volumetric fraction, and geometrical parameters on the dynamic response of sandwich beams under impact conditions.

Non-linear stability characteristics of randomly distributed CNT-reinforced fiber composite beams under thermo-mechanical loadings

The aim of the present study is to elucidate the non-linear stability characteristics of randomly distributed carbon nanotube-reinforced fiber composite (RD-CNTRFC) beams subjected to thermo-mechanical loading. Effective material properties of RD-CNTRFC are estimated using the Eshelby-Mori-Tanaka approach and Halpin–Tsai micromechanical techniques. The material properties are considered to be temperature-dependent, and the influence of carbon nanotube (CNT) agglomeration is also incorporated in material properties estimation of hybrid matrix. The strain-displacement relations are assumed by incorporating the higher-order shear deformation theory and geometrical nonlinearity (von Kármán). The governing partial differential equations are obtained by minimizing the total potential energy of the beam. Buckling loads of beam subjected to in-plane compressive loads are estimated using Eigen value approach. Similarly, buckling temperatures are also determined by solving Eigenvalue problem iteratively due to temperature-dependent material properties. The non-linear equilibrium paths under thermal and mechanical loadings are traced through iterative Eigenvalue approach. Numerical results are presented to elucidate the influence of various parameters like CNT agglomeration, ply sequences, span-to-depth ratio, boundary conditions, and mass fraction of CNTs.

Dispersion mechanism of nanoparticles and its role on mechanical, thermal and electrical properties of epoxy nanocomposites - A Review

The combined effect of nano-reinforcements on the mechanical performance of nanocomposites, which are a novel class of epoxy matrix hybrid nanocomposites containing multiwall carbon nanotubes (MWCNT), graphene, and nanodiamonds (NDs), is drawing substantial attention from many research communities. The discussion concentrates on the dispersion techniques adopted for the preparation of epoxy composites containing different types of nanoparticles (3-D fillers, nanofibers, nanotubes, and plate-like fillers). This review paper covers the electrical, thermal, and mechanical properties of carbon nanotubes (CNTs), graphene, and nanodiamond-reinforced epoxy nanocomposites and correlates them with the topographical features, morphology, weight fraction, dispersion state, and surface functionalization of CNTs, graphene, and nanodiamond. This review paper also summarises recent developments in the dispersion method of different carbon nanoparticles in epoxy matrix.

An Investigation of Free Vibration Characteristics of a DFG-CNTRC Thin Laminated Shell in Thermal Environment

A dynamic model of dual-functional gradient carbon nanotube-reinforced composite (DFG-CNTRC) laminated shell in a thermal gradient environment is established. The carbon nanotubes (CNTs) are supposed to be FG distribution in the functionally graded material (FGM) consisting of metal and ceramic components, and its traveling wave vibration in thermal gradient environment environments is studied. The temperature between the internal and external sides of laminated shell varies linearly. Considering the impact of the thermal environment on material properties, the orthogonal polynomials are used as admissible function, and the vibration differential equation of the DFG-CNTRC laminated shell is obtained by using the Rayleigh–Ritz method. First-order shear deformation theory (FSDT) and artificial spring technique are applied to establish a general model of free vibration of rotating DFG-CNTRC laminated shells under arbitrary boundary in the thermal gradient environment. The effects of rotational speed, the environmental temperature, the thickness of the middle layer, and volume fraction of CNTs on the traveling waves are discussed.

A Multifunctional Composites Membrane Aiming at Flexible Sensor and Ultrabroadband Electromagnetic Wave Absorption

A study was conducted on SEBS-based composites granules containing different volume fractions of carbon nanotubes (CNTs) using a twin extruder and hot pressing procedure to produce a SEBS/CNTs membrane. SEM was used to study the membrane s morphology, revealing a 3-D network of CNTs. TGA was utilized to measure the degradation temperature of SEBS polymer and determine the actual volume fraction of CNTs. The mechanical properties, electrical conductivity, and cyclic strain sensing behavior of the SEBS/CNTs were investigated using a tensile testing machine and pico-ammeter. Mathematical models were used to fit the measured data, demonstrating the strain sensing potential of the composites. The composite membrane with 2 wt.% of CNTs exhibited superior electromagnetic wave absorption performance with a minimum reflection loss (RLmin) value. This study provides promising opportunities for the development of advanced materials.

The effect of interphase and agglomeration on the mechanical properties of aluminum matrix nanocomposites reinforced with carbon nanotubes

The interphase phenomena are a critical problem for estimating the mechanical behavior of carbon nanotube-reinforced aluminum composites. In this research, the Aluminum-carbide (Al4C3) interphase and carbon nanotubes (CNTs) agglomeration effects on the mechanical properties of Aluminum /Carbon nanotubes composites are investigated using a numerical micromechanical model. Moreover, the impacts of the CNTs fraction, agglomeration, Al4C3 interphase, and their diameter on the elastic modulus of Aluminum (Al) composites are explored. The results demonstrated the effect of CNTs agglomeration and Al4C3 interphase on Young’s modulus of Al composites significantly when the CNT fraction increases; In addition, it observed that with increasing interphase thickness, Young’s modulus of Al composites increases and is changed with variation of agglomeration shape. The Literature’s experimental results validated the applicability of the present finite element (FE) model. The results of this study are hard evidence for CNT/ Aluminum composites creating potential applications in industry, especially for automobile and aircraft fields.