Properties Of Composite Materials Research Articles

Carbon-nanotube-grafted glass-fiber-reinforced composites: Synthesis and mechanical properties

Glass fibers (GFs) are commonly used as reinforcements for advanced polymer composites. To improve the interfacial shear properties and mechanical properties of GF-reinforced composites (GFRPs), carbon nanotubes (CNTs) are directly grafted onto GFs using chemical vapor deposition (CVD). However, this process requires high temperatures, which causes thermal degradation of GFs, deteriorating their mechanical properties. In this study, a low-temperature CNT-grafting process was investigated using a bimetallic catalyst introduced onto a GF fiber surface via precursor solutions. The mechanical properties of the CNT-grafted GFs fabricated at different CVD temperatures were evaluated; they consistently showed low tensile strengths at temperatures above 400 °C. Subsequently, various CNT-grafted GFRPs were manufactured, and their mechanical properties were characterized. Interestingly, the flexural strengths of the composites increased with maintained tensile strength, despite a deterioration of the CNT-grafted GF reinforcements due to the CVD process. This could be attributed to the improved interfacial shear strength (IFSS) of the CNT-grafted GFs at the fiber level, and the enhanced compressive strength and interlaminar shear strength (ILSS) of CNT-grafted GFRPs at the composite level. Considering the properties of GF through CVD processes, particularly in relation to temperature, and factors such as IFSS, ILSS, tensile, compressive and flexural properties of composite materials, grafting CNTs on GF via a CVD system demonstrated its highest optimality at 450 °C.

Geopolymeric Composites Containing Industrial Waste Reinforced with Arundo donax Fibers

Traditional Portland cement-based composites have a great environmental impact. Alkali-activated binders can offer an alternative, particularly if they can be obtained even partially from waste. Two residuals derived from the finishing steps of the traditional ceramic industry have been used as possible polymerizable sources mixed with metakaolin. Moreover, to contrast the low dimensional stability of alkali-activated materials and their mechanical brittleness, natural fibers derived from the Arundo donax plant have been added to the mortars. The use of renewable natural fibers instead of synthetic ones can contribute a further environmental advantage. The fresh (consistency) and cured (mechanical) properties of composite materials prepared with residuals and metakaolin were analyzed here. For comparison’s sake, a reference set of composite materials not loaded with fibers but with an identical binder/sand and liquid/binder ratio was cast. A room-temperature curing condition was selected that, although inadequate to promote the short-time reactivity of the wastes, has a minimal energy requirement and allows on-site applications. A small-scale decrease in the properties in the compression mode tests was observed in the waste-modified mortars, while the Arundo addition improved their flexural strength and dimensional stability.

Universal three-dimensional finite element for analyzing of elastic inhomogeneous shells under thermomechanical loads

The work is devoted to the development of a new modification of the finite element intended for the calculation of inhomogeneous composite shells of thin and medium thickness. The element is constructed on the basis of a universal three-dimensional isoparametric 8-node multilayer finite element of a continuous medium. The layers of the modified finite element are made of composite materials reinforced with continuous unidirectional fibers. Within the framework of a finite element model of a multilayer shell of stepwise variable thickness, a technique for modeling the properties of a unidirectional fibrous composite material has been developed, based on a method for structuring material inhomogeneities iby thickness and by plan. The shell can consist of an arbitrary number of layers of varying thickness bonded into a single piece. Each layer can have its own type of material: traditional or composite. Effective physical and mechanical characteristics of the layer material are determined using known micromechanical methods for predicting the thermoelastic constants of a fiber composite through the known physical characteristics of the matrix and fiber. The fibrous material of the layer is presented as homogeneous transversely isotropic with planes of isotropy normal to the direction of reinforcement. Additional variable parameters of the "basic" universal finite element are supplemented with new attributes that determine the thermoelastic properties of the composite components. The new parameters are related to the choice of the type of fibrous composite material in the layer of the finite element, to the setting of structural micromechanical parameters of its components, and to the setting of the reinforcement orientation angle. This allows the calculations to use both traditional and fiber-composite materials in layers of inhomogeneous shells. Numerical examples demonstrate the effectiveness of the developed approach.

Mechanical properties of solid waste-based composite cementitious system enhanced by CO2 modification

Utilizing CO2 to modify solid waste and produce high-performance cementitious material is a promising strategy. In this study, circulating fluidized bed fly ash (CFBFA), calcium carbide slag (CS) and flue gas desulphurization gypsum (FGDG) were prepared by mixing CO2 to produce cementitious materials. The impacts of CO2 on mechanical properties and carbonation reaction mechanism of composite materials were investigated. The results shown that the microstructure and mechanical properties of the gelling materials were improved by CO2 modification. When the CO2 mass transfer conditions as followed: CO2 flow rate was 1.5 L/min, stirring rate at 600 r/min, and stirring time at 20 min, compressive strength of modified material was 22 % higher than that of the non-CO2 modified material. Additionally, the density increased by 3.2 %, and porosity was reduced by 34.1 %. Among them, TG/DTG analysis found that the highest effective fixed CO2 rate was 11.1 %. The ultrasonic nondestructive testing also shown that the structure of the CO2-modified cementitious material was significantly better than that of the CFBFA-CS-FGDG composite cementitious system, and the ultrasonic loss rate was reduced by 9.4 %. Therefore, the use of CO2 to modify the composite system was of great significance for the realization of CO2 storage and the improvement of the properties of composite materials. One interesting future possibility is solid waste-based grouting materials production at energy plants: CFBFA, CS and FGDG can be used to capture CO2 from flue gases, thus improving the strength of produced grouting materials.

Sound Characteristics and Mechanical Properties of Metal Powder Chamber Structures Composite Materials Formed by Laser Powder Bed Fusion

Granular damping technology is a widely used method in aerospace and other industries to reduce vibration and noise. However, the technique still faces challenges such as secondary processing, additional structure, single structure, and residual stress. This article introduces a new composite material, the metal powder chamber structure (MPCS), formed through the laser powder bed fusion technology. The article explores the effects of factors like arrangement mode, volume fraction, and powder chamber diameter on the sound and mechanical properties of MPCS. The study shows that MPCS improves the sound insulation effect of the material and defies the mass law of sound insulation. The sample 4B40 using a body‐centered cubic arrangement has a sound insulation coefficient of 52 dB. The sound absorption efficiency curve presents a double peak, and the sample 6F60 exhibits the highest sound absorption efficiency of 0.76. MPCS changes the deformation stage of the material stress–strain curve, and different MPCS also alters the compression deformation mode of the composite material. By studying the effects of MPCS on sound and mechanical properties, it is hoped to provide a better and more sustainable solution for vibration and noise reduction.

Preparation and Characterization of Polyvinyl Alcohol (PVA)/Carbonized Waste Rubber Biocomposite Films.

The technological properties of composite materials (thermal, strength, rheology, electrical and morphology) are very important parameters for high-performance applications. In this study, we aimed to improve the properties of PVA by using carbon materials obtained by the pyrolysis of waste tires, with the aim of recycling them instead of disposing of them. For this purpose, PVA biocomposite films containing carbonized waste rubber at different rates were prepared. The thermal properties of the prepared biocomposite films were examined via thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) methods. While rheological measurements were carried out with a rheometer, bulk conductivities were measured with a pico-ammeter. In addition, the morphology of biocomposite films was determined via field emission scanning electron microscopy. The nanomechanical properties of biocomposite film was investigated via XPM analyses. According to the rheological measurements and nanoindentation hardness results, it is understood that as the amount of carbonized waste rubber increases, flexibility decreases and harder and brittle structures are observed in biocomposite films. The electrical measurement results showed that electrical conductivity increased as the amount of carbonized waste rubber increased. When all the results obtained were evaluated, it could be concluded that biocomposite films obtained by increasing the electrical conductivity and hardness of PVA can be used in the electronics industry.

Synergistically Optimized Thermoelectric and Mechanical Properties of Mg3.2Bi1.5Sb0.5-SiC Composites.

Motivated by the surging demand for low-temperature waste heat harvesting, materials with both prominent thermoelectric and good mechanical properties are preferred in practical applications. In this present work, the composite exploration of Te-doped Mg3.2Bi1.5Sb0.5-x vol % nanosized SiC (x = 0, 0.05, 0.1, 0.2, and 0.5) was carried out, where nanosized SiC is physically dispersed in the matrix in the form of a second phase. SiC second phase compositing further optimized the matrix carrier concentration, resulting in a higher power factor in the service temperature range (the highest value from 28.9 to 31.7 μW cm-1 K-2), and the (ZT)ave from 0.91 to 0.96 compared with the matrix sample. In addition, the SiC second phase effectively enhanced the mechanical properties of composite materials, including flexural strength, microhardness, and modulus. Because of the simultaneous optimization of thermoelectric and mechanical properties, the overall performance of Te-doped Mg3.2Bi1.5Sb0.5-0.05 vol % SiC composite is leveraged to meet special requirements of power generation. It is expected that the addition of SiC should be broadly applicable to address the physical performance in other thermoelectric systems.

A node graph using SEM images for material properties prediction with a case study of composite material

Establishing a mapping model between the microstructure and material properties of composite materials is crucial for material development. Scanning electron microscope (SEM) images are widely used for the prediction of material properties. However, the prediction from a single SEM image is independent and does not fully reflect the microstructure characteristics. To address this issue, this paper proposes a node graph construction strategy for SEM images and establishes a multi-graph-based graph attention network (GAT) material property prediction model to achieve the convergence of mutual complementation in microstructure features by using GAT. Firstly, multiple SEM images are constructed into node graphs by a microstructure feature encoder. Next, the microstructure features of multiple SEM images on the node graphs are mutually complemented and converged by using GAT. Finally, the prediction is carried out by using multiple SEM images. The experimental results show that the proposed method shows better performance than other methods.

Improving dispersion of basalt fiber with polyethylene glycol and effect of coupling agent

ABSTRACT Basalt fibers were widely used as reinforcing matrix materials because of their thermal and chemical stability and environmental friendliness. The properties of composite materials were affected by the interaction between the basalt fibers and matrix materials. Surface modification of basalt fibers and the dispersion property have become key points of research in recent years. This study focuses on the impact of a dispersant on surface modification. Basalt fibers were dispersed by polyethylene glycol (PEG) before modification with 3-aminopropyltriethoxysilane (KH550), which significantly increased the surface roughness, thus increasing the surface area and facilitating mechanical bonding. The morphology, structure, and composition were characterized via scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy analysis (XPS), respectively. The distribution characteristics of fiber were evaluated by the response surface method. When the mass fraction of PEG was 0.5 wt.%, the modification time was 2.5 hours, and the modification temperature was 60°C, the fiber dispersion degree in KH550 solution reached 83%. The grafting degree test indicates that the weight of the grafting increased to 6.67 times that of the undispersed basalt fibers. This enhancement allowed for greater grafting of the KH550, thereby optimizing the effect of modified fibers.

The influence of ceramic powder modification temperature on copper-based composite materials: A perspective on mechanical and frictional behavior

To enhance the bonding capability of composite ceramic powder and subsequently improve the friction stability of copper-based composite materials, B4C-SiC ceramic powder modified at different temperatures was used. The results indicate that elevating the modification temperature of ceramic powder promotes faster growth of particles and enhances inter-particle bonding. The mechanical properties of the copper-based composite material are significantly improved, particularly at 1400 °C, owing to the filling of pores and the particle reinforcement effect of ceramic. Meanwhile, the friction coefficient and wear exhibit a gradual increase, mainly caused by the formation of microasperities from larger ceramic particles and sepiolite, leading to changes in the friction-film and friction mechanism. The primary wear mechanism shifts from abrasive wear (1200 °C-1300 °C-1400 °C) to oxidative wear (1500 °C).

Extraction and characterization of nano-silica particles to enhance mechanical properties of general-purpose unsaturated polyester resin

Abstract Unsaturated polyester resin (UPR) is the most versatile liquid polymer with a wide range of applications in every aspect of the industry but it has low impact strength, low elongation at break, and low toughness. Its mechanical properties can be enhanced with the addition of an optimum percentage of nano-silica fillers by using ASTM polymer test standards, which have been followed by various research groups. For this research, enhanced mechanical properties of the resin have been tested for 0.5, 1, 2, 3, and 4% amount by weight fraction of the nano-silica as fiber nanomaterial. The sugar cane bagasse ash was collected from the Wenji Sugar Factory and extracted with the required size of the particle, which is 10 nm. The ability of extraction is used to manipulate the particle size as the researcher needs. The aim is to determine the enhanced mechanical properties of the UPR by the addition of optimum nano-silica particles. Nanoparticles have the effect of filling porous regions, crack path deflection, and crack bridging capability of the material, which provides good adhesion with the matrix to increase the mechanical properties of composite materials. Experimental result dictates that 0.5% nano-silica addition with 10 nm particle size performs best by enhancing the mechanical properties of composite material up to 30.45% for tensile, 33% for compression, 17.8% for flexural, a slightly 10% improvement for impact test and it shows an overall 27% better performance than the pure UPR. Thermal stability and glass transition temperature were not influenced by the addition of nano-silica.

Experimental analysis of mechanical properties of e-waste composite materials with dual glass fibers

This study aimed to evaluate the mechanical characteristics and application of e-waste as a filler for glass fiber composites made of S and E (e-waste + S E). Metal, printed circuit boards, integrated circuits, diodes, and transistors were separated from the e-waste filler during milling. S and E glass fiber, epoxy, and filler were utilized in proportions of 10%, 10%, and 70%, respectively, on a volume basis. The hand lay-up technique was used to construct composite specimens. Scanning electron microscope analysis was used to gauge how filler loading affected the morphology of composite materials. The composite has a compressive strength of 23.760 MPa, which is 69.71% higher than the Geo poly composite. The tensile strength of this composite is withstood up to 16.078 MPa. It has 53% better tensile properties than Sunflower Husk composites with the same operating conditions. It gives a resistance up to 42 D during hardness test to withstand. It was 15.6% better than the NF30% epoxy composite specimen. The e-waste + S E composite gives a great opposite force of up to 2 kJ on the impact load test.; it was 86.9% higher than fly ash epoxy composites.

Mathematical modeling of the creation process and aging of polymer composite materials

Based on the analysis of the literature on the possibility of using neural networks to create new materials with high functional properties, the article considers a solution to the problem of determining the operational stability of polymeric composite materials by creating physical and chemically sound mathematical prediction models. Epoxy resins of the UP-637 and EA brands with an isophorone diamine hardener were chosen as the matrix of the model composite material, and oligobutadiene rubber of the SKN-10 KTR brand was chosen as the modifier. It justifies directions of work necessary for development of new materials creation methodology with optimal characteristics, building a model for changing the properties of materials at variation of composition and implementation of full-scale mathematical modeling of physical and chemical processes of polymer composite materials aging at changing level and time of climatic factors influence. Verification of the obtained dependence of service characteristics on the composition of the material and the level of influencing climatic factors was carried out on the basis of data from full-scale tests in a temperate climate. The proposed methodology for modelling the properties of polymer composite materials will reduce the development time of new materials and allow creation of polymer composites based on epoxy resin containing fillers of various natures (carbon, mineral and polymer) with high performance parameters.

Utilizing Upcycled Graphene Nanoplatelet-Coated Glass Fibers as a Performance Booster and Compatibilizer for Enhanced Mechanical Performance of Polypropylene/Glass Fiber/Graphene Nanoplatelet Composites.

The high usage ratio and elevated density of glass fibers (GFs), often surpassing twice that of polymers, can contribute to undesired increases in the overall density of polymeric materials. One potential solution is the incorporation of graphene as a secondary additive, offering a lower specific gravity and exceptional mechanical properties. In light of this, waste tire-derived graphene nanoplates (GNPs) were optimized for coating onto GFs by considering factors such as surface treatment of the fiber, the dispersion quality of GNP, and the coating technique. The resulting GNP-coated GF (GNP-c-GF) was initially incorporated into pure polypropylene (PP) at low weight percentages (0.1-1 wt %), and 31% increase in the tensile modulus was achieved compared to neat PP. Subsequently, 1 wt % GNP-c-GF was utilized as a compatibilizer in PP/GF/GNP composites to enhance the compatibility between GNP and GF. By strategically incorporating GNP and GNP-c-GF at a lower GF ratio, the detrimental impact on the tensile modulus of 30% GF-filled PP was effectively mitigated, leading to a remarkable enhancement to an impressive value of 5658 MPa. The successful integration of GNP and GNP-c-GF exemplifies their promising potential as additives for achieving superior mechanical properties in composite materials, while concurrently promoting the utilization of recycled content.

A Real Test and Simulation Result Comparison of Selected Properties of Hybrid Composite Materials

In this study, the notion of composite materials is thoroughly assessed. Actual and simulation in a specific computer software stress testing of hybrid composites are investigated. The paper deals with the mechanics of rigid bodies, their elasticity, strength, and stiffness. In addition to a general overview of the former’s behavior and properties, this paper presents the possibility of calculating the bearing capacity of various materials in relevant computer programs. The production and testing process of the composite samples are described. The latter are then subjected to simulated tests in computer software. The main objective of this study is to compare real test results of hybrid composites, namely combined carbon fibers, glass fibers, aramid-carbon fibers, aramid honeycomb, and metal mesh with the simulation findings.

Investigation of Mechanical, Thermal Properties of Camel wool Fiber and Chopped E-Glass Fiber Reinforced Epoxy Resin with and without Addition of Iron Oxide

Composites are an excellent alternative to metal alloys due to their high strength-to-weight ratio. It's awesome that researchers are working on biodegradable and recyclable fiber-reinforced composites. Each natural and synthetic fiber has advantages and disadvantages, but combining different fibers alters the properties of composite materials. In this project, we used camel wool fiber and chopped E-glass to make a hybrid composite with epoxy as the matrix. Combining different fibers in composite materials, it is possible to alter their properties and create materials with specific characteristics. Additionally, adding fillers to composites can further enhance their characteristics, such as improving strength, stiffness, and other mechanical and thermal properties. We also experimented with different amounts of iron oxide which resulted in these semi-biodegradable materials. The mechanical and thermal characteristics of these composites improved as the iron oxide powder content rose. The best part is that using iron oxide as a filler material can help reduce material costs. Key Words: Chopped E glass (CEG), Camel wool Fiber (CWF), Filler, Differential thermal analysis (DTA), Thermogravimetric analysis (TGA), Derivative thermogravimetry (DTG).

Study on the melting characteristics of composite phase change materials and the power generation performance of coupled thermoelectric systems under supergravity conditions

Miniaturization and integration of electronic equipment in aircraft have resulted in a substantial increase in thermal load. However, aircraft often experience acceleration maneuvering flights in supergravity environments, which makes comprehensive research on thermal management under supergravity conditions necessary. The influence of gravity on the thermal storage properties of composite phase change materials doped with graphene nanoparticles (GNP-PCM) was investigated in this study by simulation. Under 2g, 4g, 6g, 8g, and 10g gravity conditions, the melting time is reduced by 14.86%, 27.05%, 33.31%, 37.00%, and 39.79%, respectively, compared with normal gravity conditions. Moreover, the integration of the PCM with a thermoelectric power system facilitated waste heat utilization. Incorporating GNPs markedly enhances power generation efficiency under 10g supergravity conditions. With an open-circuit voltage of 0.8 V and a maximum output power of 0.11 W, the power generation reached 81.62 J, which is 53.91% higher than that of pure PCM. This enhancement can be attributed to the improved natural convection and accelerated melting rate facilitated by the GNPs. This study elucidates the underlying physical mechanisms affecting the melting rate of PCM under increased gravity conditions. Furthermore, coupling PCM with a thermal power generation system provides a rational approach for the reuse of waste heat.

Repercussion of natural silk fibers from spider and silkworms on the mechanical properties of composite materials

Costly synthetic fibers like kevlar, glass, and carbon lead to expensive production costs for products made from these materials, necessitating the development of alternate materials. As a more sustainable and affordable substitute for synthetic reinforcement materials like glass, carbon, and kevlar, natural fiber has gained popularity. Silk fiber obtained from spiders and silkworms is one type of natural fiber that has excellent mechanical properties such as tensile strength, tensile modulus, and breaking elongation. Its mechanical and biocompatibility characteristics are unmatched by those of other synthetic and natural fibers. This article discusses various silk fiber-related topics such as chemical composition, mechanical properties, and applications with respect to spiders and silkworms. Also, the requirement for silk fiber to be used as a reinforcement in composite materials is highlighted. Furthermore, the mechanical properties of silk fiber-reinforced composites (SFRCs) are also explored in this review. It is acceptable to draw the conclusion that the use of SFRCs in the creation of useful and possibly lucrative applications as novel materials in many industrial areas is inevitable.

Thermal Properties Characteristic of Aluminium-Alumina Composite for Solar Water Heating System Application

Thermal Energy Storage (TES) is an energy storage mechanism or material with modern technology at low costs, such as metal, concrete, composites, and others. Aluminum (Al)–Alumina (Al2O3) Composite is a solid material with high strength and hardness characteristics that can work in low-temperature applications. This study aims to analyze the features of the thermal properties of composite materials in the form of thermal conductivity and specific heat capacity. Composite specimens were prepared using powder metallurgy techniques. The weight fraction of alumina in the composite is 35%, 50%, and 65%. There are three (3) composite models, namely C1(35Al-65Al2O3), C2 (50Al-50Al2O3), and C3(65Al-35Al2O3). Models were made using the cold compaction method with a compressive load of around 20-25 MPa, and the specimens were fired in a furnace at a temperature of 550 °C with a holding time of 30 minutes. Scanning Electron Microscopy analyzed the microstructure of the composites. Composite thermal conductivity test using a thermal conductivity apparatus, and composite heat capacity test using a Differential Scanning Calorimetry (DSC). The results showed that C1(35Al-65Al2O3) composite had higher density and specific heat capacity than C2 and C3 composites. The theoretical density and specific heat capacity values of the C1 composite are 3.39 g/cm3 1.36 J/g.°C. However, the value of the thermal conductivity of C1(35Al-65Al2O3) material is lower than the other composites with a value of 0.37 W/m.°C. The greater the percentage by weight of alumina in the aluminum-alumina composite, the more theoretical density and specific heat capacity will also increase. Still, the thermal conductivity of the composite will decrease. Composite C1 35Al-65Al2O3 can potentially be a heat energy storage material used in solar water heating systems because of its high density and heat capacity.

Prediction of particle-reinforced composite material properties based on an improved Halpin–Tsai model

This paper introduces an improved Halpin–Tsai model to predict the mechanical, thermal, and electrical properties of silicon-carbide-reinforced polypropylene composites. The model considers the influence of porosity and corresponding silicon-carbide volume fractions and derives relationships between material property shape factors and the aspect ratio, silicon-carbide volume fraction, and porosity. The improved model’s predictions exhibit errors of 4.00% for mechanical properties, 2.13% for thermal properties, and 2.24% for electrical properties when compared to finite element analysis. This study demonstrates that the improved Halpin–Tsai model can effectively predict the properties of silicon-carbide-reinforced polypropylene composites, aiding in the design and optimization of these materials.