Fabric-reinforced Composites Research Articles

Interlaminar toughening of carbon fiber/epoxy composites via interleaving co‐polyamide (Co‐PA) veils

AbstractThermoplastic veil interlayers offer a promising approach to improve interlaminar reinforcement in composite materials. This study investigates co‐polyamide (Co‐PA) interleaved veils, fabricated through the hot melt adhesive (HMA) technique. These veils are then applied with varying areal weight densities as interleaves to simultaneously toughen and strengthen carbon fiber/epoxy (CF/EP) composites, utilizing the vacuum‐assisted resin infusion (VARI) method. Integrating Co‐PA veils with a low melting point in the interlaminar of CF/EP composites improves compatibility and promotes strong adhesion between thermoplastics and epoxy resins. As result, The Co‐PA laminates exhibited significant improvements compared with the untoughened composites, with a maximum enhancement of 148.1% and 67.8% for Mode‐I (GIC) and Mode‐II (GIIC), respectively. Moreover, ILSS, tensile strength, and flexural strength improvements were also 20.9%, 34.9%, and 14.5%, respectively. The fracture surface analysis via scanning electron microscopy directly revealed the crack propagation on the fracture surfaces of Mode‐I and Mode‐II specimens. This analysis revealed that Co‐PA demonstrated excellent compatibility with epoxy resin, melts during the stage of epoxy curing, and undergoes phase separation in the later stage, resulting in the formation of “bead‐like” structures within the fibrous network. Remarkably, this structure significantly enhanced the toughness of the CF/EP composites. The Co‐PA veils can improve the interlaminar toughness of CF/EP composites due to their compatibility with the epoxy matrix and high inherent toughness and strength. This method is straightforward to manage and can be utilized for manufacturing large‐scale composite materials incorporating CF fabrics, demonstrating promise for industrial applications.Highlights With its low melting point, co‐polyamide helps prevent structural failure or excessive damage and is proposed to be utilized in composites to enhance the interlaminar fracture toughness properties. The effects of Co‐PA veils of different areal densities on the mechanical characteristics of interlaminar composites were examined. Co‐polyamide particles with fiber‐carbon laminates offer superior fatigue properties and an optimum carbon fiber‐bridging mechanism. Co‐polyamide veils with CF/EP laminates are feasible for structural use in high‐tech automotive applications.

RESEARCH SOLUTIONS FOR PRECAST CONCRETE REVETMENTS USING ALB-REBAR TO RETAIN CORAL SAND FOR OFFSHORE ISLANDS IN VIETNAM

Gravity revetment solutions are a popular choice for shore protection at atolls under the harsh conditions of ocean waves. The precast revetment option is preferred to reduce shipping costs for materials and ensure quick construction. This article studied precast concrete revetments with ALB composite material reinforcement and conducted experimental research to determine the shear resistance characteristics of coral sand and the friction characteristics of concrete materials with coral sand. Based on the experimental parameters, the authors calculated the stability of the ALB embankment structure against the effects of wave loads during storms. With experimental data obtained from coral sand samples prepared with equivalent density in the field, the results showed that the stability coefficient of the revetment is significantly higher than the one obtained from the traditional calculation concept.

Mechanical Characterization, Water Absorption, and Thickness Swelling of Lightweight Pineapple Leaf/Ramie Fabric-Reinforced Polypropylene Hybrid Composites.

Fiber-reinforced composites are among the recognized competing materials in various engineering applications. Ramie and pineapple leaf fibers are fascinating natural fibers due to their remarkable material properties. This research study aims to unveil the viability of hybridizing two kinds of lignocellulosic plant fiber fabrics in polymer composites. In this work, the hybrid composites were prepared with the aid of the hot compression technique. The mechanical, water-absorbing, and thickness swelling properties of ramie and pineapple leaf fiber fabric-reinforced polypropylene hybrid composites were identified. A comparison was made between non-hybrid and hybrid composites to demonstrate the hybridization effect. According to the findings, hybrid composites, particularly those containing ramie fiber as a skin layer, showed a prominent increase in mechanical strength. In comparison with non-hybrid pineapple leaf fabric-reinforced composites, the tensile, flexural, and Charpy impact strengths were enhanced by 52.10%, 18.78%, and 166.60%, respectively, when the outermost pineapple leaf fiber layers were superseded with ramie fabric. However, increasing the pineapple leaf fiber content reduced the water absorption and thickness swelling of the hybrid composites. Undeniably, these findings highlight the potential of hybrid composites to reach a balance in mechanical properties and water absorption while possessing eco-friendly characteristics.

Experimental shear behaviour of masonry walls reinforced with FRCM

The shear strength of piers and spandrels is a crucial factor in masonry buildings, affecting structural safety. Such a strength can be increased in several ways, particularly by using fiber reinforced cementitious matrix (FRCM) reinforcements. These reinforcements can be applied symmetrically on both sides of the wall or only on one side. As it is well known, the FRCM-to-substrate adhesive properties strongly affect the effectiveness of such reinforcements. Moreover, a complete covering of the reinforced surface with bidirectional mesh evenly distributes the stresses, improving the load-bearing capacity. Appropriate test methods, for example diagonal tests, can be effectively used to evaluate the shear capacity of masonry panels, even with externally bonded composite material reinforcements, and the corresponding failure mechanism. This paper describes the results of an experimental campaign involving masonry panels, made with three different types of mortar, also reinforced with a PBO-FRCM system, subjected to diagonal tests. Through the experimental results, it was possible to determine the shear capacity of the panels, identify the failure mechanisms and evaluate the effectiveness of the FRCM reinforcements. The predictive capability of design formulas proposed in the literature for evaluating the shear capacity of unreinforced and reinforced masonry panels has been analyzed in the paper.

Experimental and numerical approach to understand the role of defects in damage mechanisms of flax fibers at bundle scale

Flax fibers represent a valuable reinforcement in composite materials. However, the presence of defects known as kink-bands in flax fiber has the capacity to influence their mechanical properties. The primary objective of this research is to gain a comprehensive understanding of the damage mechanism in flax fiber bundles presenting a novel aspect due to the intricate structure of bundle fibers, which is more complex compared to elementary fibers. The study specifically explores flax fiber bundles under tensile loading and investigates the impact of kink-bands on their failure through a combined approach, utilizing both experimental and numerical methods. In the experimental part, X-ray microtomography in situ tensile testing is carried out, which reveals complex failure mechanisms. Furthermore, a 3D-Finite Elements (FE) model is implemented utilizing 3D reconstructed fiber and used for numerical tensile analysis. Our findings highlight that the kink-band region acts as prominent failure site in fiber bundles with significant stress concentration at the kink-band region, mainly induced by local porosity.

Experimental study on the effects of SS304 and Aluminium reinforcements on mechanical and vibration properties in jute‐epoxy composites

AbstractJute fiber has emerged as a promising reinforcement material in polymer composites, and researchers are actively exploring hybrid composite materials to overcome its individual mechanical property limitations and enhance overall performance. The paper introduces a unique hybridization of polymer composites that harnesses the advantages of stainless steel and aluminium offering a lightweight material for potential engineering applications. In this study, stainless steel 304 wire mesh (S), aluminium wire mesh (Al) and aluminium perforated sheet (Alp) are used as an additional reinforcement along with jute (J) and glass (G) fibers to fabricate hybrid polymer composites with varying volume fractions of SS304 and Al wire mesh. Seven laminates of hybrid composites namely J/J/J/S/J/J/J, J/J/S/J/J/S/J/J, J/J/J/Al/J/J/J, J/J/Al/J/J/Al/J/J, J/J/J/Alp/J/J/J, G/J/J/J/S/J/J/J/G, (J/J/S/J/J/S/J/J)450 along with virgin composite laminate J/J/J/J/J/J/J/J were fabricated and tested to obtain mechanical and vibration properties. Bonding between metal wire and matrix is investigated and reported through ILLS tests and SEM observations. Experimental findings indicate a notable 24% and 7% increase in tensile and ILSS strength, respectively, with SS304 reinforcement. Moreover, significant improvements in flexural and impact strength, approximately 48% and 33% for J/J/S/J/J/S/J/J, demonstrate the effectiveness of the hybrid approach. The J/J/S/J/J/S/J/J laminate excels in damping capacity under various boundary conditions. The study underscores the potential of metallic reinforcement to enhance the mechanical properties of jute fiber‐reinforced polymer composites, presenting opportunities for the development of lightweight, sustainable, and high‐performance materials in engineering applications.Highlights Developed jute fiber‐based hybrid polymer composites with metal wire reinforcement. Significant increase in strength and stiffness observed with addition of metal wires. Bonding between metal wire and matrix is investigated through ILLS tests and SEM observations. Vibration damping of all hybrid materials is reported. Study provides valuable data to develop sustainable, lightweight, and cost‐effective materials.

Study and Characterization of Algerian Spart Cellulosic Fibers (Lygeum spartum): Effect of Alkali and Acid Treatments on Their Physicochemical and Morphological Properties for Papermaking

Recently, non-wood plants have increasingly gained attention, due to their versatile advantages like cost and fast-growing period. The purpose of this study was to examine the effectiveness of different treatments on Algerian Spart fibers (Lygeum spartum) using sodium hydroxide at various concentrations (8, 10, 15, and 22% NaOH), and sulfuric acid at 30% for 2h at 100 °C. Fourier infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses were used to characterize the microstructural changes in the treated fibers. The results of FTIR confirmed the presence of cellulose in the raw fibers with a crystallinity index of 49.4%. The FTIR and XRD studies showed that an 8% NaOH treatment eliminated the amorphous constituents and improved the crystallinity index. Also, SEM micrographs confirmed the removal of impurities; for the acid treated fibers a pseudo-lignin was formed and deposited on fibers surfaces in the form of spherical droplets. Moreover, a decrease in the yield of cellulose at high alkali concentrations was noticed. The results suggest the possibility of exploitation of Spart fibers and their application in papermaking and as a reinforcement in composite materials.

Characterizing Cryptostegia grandiflora stem fiber for reinforcing lightweight polymer composites: A comprehensive study of its physical, chemical, and thermal properties

This study aimed to characterize Cryptostegia grandiflora stem fiber (CGSF) as a potential reinforcement material for lightweight polymer composites. Natural fiber-reinforced materials have gained attention as a promising alternative to synthetic fibers due to their comparable strength and modulus, and lack of harmful chemicals. The physical, chemical, and thermal properties of CGSF were investigated through fiber roughness, chemical measurement, physical measurement, Fourier transform infrared spectroscopy, XRD, water absorption, thermogravimetric analysis, and SEM conformation analysis. The results showed that CGSF has a high cellulose content (80.3 wt.%) and specific strength, making it suitable for use in polymer composites. Its flaky layered outer surface provides a high modulus, and its low microfibril angle observed through electron microscopy results in strong bonding qualities. The fiber also demonstrated improved heat stability up to 254–387 °C through thermogravimetric analysis, meeting the requirements for polymerization. These findings demonstrate the potential of CGSF as a natural reinforcement material for lightweight polymer composites.

Winter flax: Stem structure, fibre properties and reinforcement potential for composite materials

Climate change is characterized by rising temperatures and an increased risk of spring water deficit, both of which threaten the cultivation of textile flax. With the multiplication and intensification of these phenomena, fibre plant yields have become increasingly uncertain in recent years, leading to shorter stems as well as reduced yields. In this context, winter flax cultivation emerges as a solution to sustain the exploitation of this plant. Sown before winter, it can resist periods of spring water stress, owing to the early development of it root system, and is also protected from the summer heat. In this study, we investigate the stem architecture and fibres properties of two winter flax varieties, in comparison to spring flax. Cross-sections reveal that both winter and spring flax have a similar plant structure. The part located at mid-height of the winter stem contains the most fibres, accounting for around 23% of the biomass. At the middle of the stem, the elementary fibres of the Cirrus and Olga varieties have an average length of 20.9 ± 7.7 mm and 30.0 ± 10.8 mm, respectively. At this same plant height, winter flax fibres of the Cirrus and Olga varieties have an average Young’s modulus of 63.6 ± 18.8 GPa and 57.6 ± 20.8 GPa, and an average strength at break of 1248 ± 554 MPa and 1187 ± 627 MPa, respectively. As a conclusion, winter flax has a similar length and mechanical properties to spring flax and therefore offers the same potential for textile applications. In addition, as demonstrated in this study, winter flax can be similarly useful as a reinforcement in composite materials.

Development and Characterization of Hybrid Particulate-fiber Reinforced Epoxy Composites

Although considered wastes, animal fibers and gastropod shell particles are biodegradable, have low density, high stiffness, considerably high impact absorption capacity and relatively low cost. Therefore, they are finding increasing use as reinforcement materials in polymer composites. This research work studied the tensile, hardness, and wear resistance properties of hybrid snail shell (SSP) and chicken feather barb fibers (CFB) reinforced epoxy composites. The stir cast molding technique was utilized to synthesize the composite samples with 3, 6, 9, 12, 15, and 18 wt.% of the hybrid SSPs/CFB. Compared with the control samples, SSP/CFB hybrid reinforcements enhanced the mechanical properties of the composites. Composites with intermediate weight fraction of 9 wt.% SSP/CFB exhibited overall optimum properties when benchmarked against the control sample with approximately 37, 37, 133, 19, and 59% improvement in wear, hardness, impact, and ultimate tensile strength properties respectively. These enhancements suggested a synergistic effect of the two reinforcement phases. The results presented in this study demonstrated the potential of utilizing bio-derived waste materials for synthesizing eco-friendly composites.

Characterization of natural cellulosic fiber extracted from Grewia ferruginea plant stem

The use of natural fibers as reinforcement in polymer composites has gained significant attention due to their eco-friendly, and biodegradability. This study aims to extract and characterize the natural cellulosic fibers from the Grewia ferruginea stem. The fibers were extracted from plant stems using sodium hydroxide and analyzed using Fourier Transform infrared spectroscopy (FTIR) to determine chemical bonds on the fiber and functional group and Thermos-gravimetric analysis (TGA) was used to determine the thermal stability and degradation temperature of the fiber. The crystalline properties of extracted fibers were characterized by x-ray diffraction and surface morphology was characterized by Scanning electron microscopy. The chemical composition of the fibers, including cellulose, hemicellulose, lignin, moisture, extractive content, and fiber linear density, was evaluated. Tensile, thermal, and FTIR studies were conducted to assess the performance properties of the extracted fiber. The analysis revealed that the Grewia ferruginea fibers contain cellulose (60.4–72.6 wt%), hemicellulose (18.5 ± 3.1 %), and lignin (13.55 ± 2.75 %). The extracted fibers have a crystallinity index of 48.76 % and crystallite size of 5.14 nm. The fiber exhibited tenacity, breaking elongation, and Young's modulus values of (52.3 ± 6.5 cN/tex), (3.6 ± 1.8 %), and 43.5 ± 2.3 GPa, respectively. FTIR studies confirmed the presence of biopolymers in the Grewia ferruginea fiber. Additionally, the fibers demonstrated thermal stability up to 275 °C based on thermogravimetric analysis. These findings suggest that the extracted natural cellulosic Grewia ferruginea fiber has the potential to be used as a sustainable reinforcement material in polymeric composites.

Assessment of mechanical properties and morphology of polylactic acid/acrylonitrile butadiene styrene blends and their carbon fabric-reinforced composites

Assessment of mechanical properties and morphology of polylactic acid/acrylonitrile butadiene styrene blends and their carbon fabric-reinforced composites

Utilizing photodeposition to fabricate micro-nano structured microcapsules for enhancing mechanical and high-temperature tribological performance of fabric composites

Fabric composite materials face significant challenges in maintaining excellent tribological properties at high temperatures. This study employed photodeposition to deposit gold (Au) and copper (Cu) nanoparticles on the surface of titanium dioxide-coated jojoba oil microcapsules (TiO2 @jojoba), yielding micro-nanostructured Au-TiO2 @jojoba and Cu-TiO2 @jojoba microcapsules. Subsequently, microcapsules participated in the in-situ polymerization of polyimide (PI), serving as crosslinking points in PEEK/PTFE fabric-reinforced composites. PEEK/PTFE-Au composites containing Au-TiO2 @jojoba microcapsules exhibited outstanding tribological and mechanical properties. Compared to microcapsule-free samples, PEEK/PTFE-Au composites showed a 30.26 % reduction in friction coefficient at 250 °C and a 24.28 % increase in tensile strength. In addition, mechanistic studies indicated that TiO2 underwent a friction chemical reaction converting to TiNF during friction accompanying by friction-induced phase transitions. The release of jojoba oil during friction and the occurrence of friction chemical reactions were the main friction reduction mechanisms of PEEK/PTFE-Au composites at high temperatures.

Design and Fabrication of Banana Fiber Reinforced Bio Composite

Abstract: This study explores the mechanical properties and potential applications of banana fiber-epoxy resin composites fabricated with an 80% resin and 20% fiber ratio using a hand layup method. The composites were comprehensively tested for tensile strength, flexural strength, impact resistance, and compression strength to assess their performance characteristics. The results highlight the effectiveness of banana fiber as a reinforcement material in epoxy composites, demonstrating promising mechanical performance suitable for structural and load-bearing applications in industries such as automotive, construction, and aerospace. The composites exhibited notable advantages, including enhanced tensile and flexural strength, good impact resistance, and high compression strength, making them viable alternatives to traditional composite materials. The sustainable nature of banana fiber further contributes to the eco-friendliness of these composites. This research emphasizes the potential of banana fiber-epoxy resin composites to develop sustainable and high-performance materials, paving the way for innovative applications in various sectors. The findings contribute valuable insights into utilizing natural fibers like banana fiber in epoxy resin matrices to enhance composite properties and promote the adoption of eco-friendly material solutions in modern industries

Construction of an Interfacial Layer of Aramid Fibers Grafted with Glycidyl POSS Assisted by Heat Treatment and Evaluation of Interfacial Adhesion Properties with Epoxy Resin.

The surface of para-aramid fibers (AFs) was modified via air-assisted heat pretreatment and solution impregnation by varying the glycidyl polyhedral oligomeric silsesquioxane (POSS) content. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy showed an ester group, confirming the graft reaction between glycidyl POSS and oxidized AFs. The mechanical properties of AFs could be altered by varying the glycidyl POSS content. The modified AFs exhibited an optimal tensile strength after embedding 5 wt % glycidyl POSS on the fiber surface. The thermal stability of the modified fibers decreased; however, no obvious changes in crystallinity were observed by varying the glycidyl POSS content. Moreover, the tensile strength of monofilament increased from 23.8 to 25.8 cN·dtex-1, the thickness of the grafted layer on the fiber surface was above 30-40 nm after the graft modification with 5 wt % glycidyl POSS, and the interfacial shear strength (IFSS) increased by 62.55% to 26.22 MPa. Thus, the modified glycidyl AFs can be used for the reinforcement of composite materials.

Voronoi cell finite element method for heat conduction analysis of composite materials.

In this paper, Voronoi cell finite element method (VCFEM) based on assumed flux hybrid formulation has been presented for heat conduction problem of particle reinforced composites material. The heat fluxes satisfying a priori internal thermal balance are directly approximated independently in the matrix and the inclusion respectively. The temperatures on element boundary and matrix-inclusion interface are interpolated by nodal temperature. The thermal balance on the interelement boundary and matrix-inclusion interface is relaxed and introduced into the functional by taking the temperature as Lagrange multiplier. In this way, a functional containing two variables of heat flux and temperature is proposed. Full field heat flux and effective thermal conductivity are obtained. Feasibility and effectiveness of the proposed approach are verified through several numerical examples.

Physical, chemical, and thermal behaviour of date palm leaflet as potential reinforcement material for green composites

Physical, chemical, and thermal behaviour of date palm leaflet as potential reinforcement material for green composites

Crushing Performances of Kenaf Fibre Reinforce Composite Tubes

The quest for sustainable and eco-friendly materials has led to a burgeoning interest in natural fibers as reinforcements in composite materials. Kenaf fiber, derived from the Hibiscus cannabinus plant, presents a promising avenue for enhancing the mechanical and energy absorption properties of composite tubes. This study focuses on the fabrication of composite tubes using a combination of kenaf fiber and epoxy resin. The composite tubes were then subjected to compressive testing to evaluate their energy absorption performances. The fabrication process involved the impregnation of kenaf fibre with epoxy resin, followed by winding and curing to form composite tubes. Different configurations of kenaf fiber content were utilized to investigate their impact on the structural integrity and energy absorption capabilities of the tubes. Compressive testing was conducted to assess the energy absorption behaviour under axial loading conditions. The results revealed that the incorporation of kenaf fiber significantly influenced the energy absorption capabilities of the composite tubes. Higher kenaf fiber content demonstrated improved energy absorption performance, showcasing the potential of kenaf fiber as an efficient energy-absorbing reinforcement. The findings of this study offer valuable insights into the use of sustainable and renewable resources, such as kenaf fiber, in enhancing the mechanical and energy absorption properties of composite structures, thereby contributing to the development of eco-friendly and high-performance materials.

Effect of aging on the mechanical properties of woven fabric-reinforced calcined diatomite substituted cement-based composites

The mechanical characteristics of polyester and flax woven fabric-reinforced, diatomite-substituted, cement-based composites have been examined at different ages within the scope of this study. The use of calcined diatomite in combination with a cement-based matrix aims to improve the mechanical performance within the composite as well as reduce carbon emissions. The consistency of cement-based and diatomite-substituted matrices with water-to-binder proportions of 0.28 and 0.45 was maintained at a fixed flow diameter of 235 mm with the adjusted use of a superplasticizer. The stress–strain graphs of the composites were obtained using an axial tensile testing machine and Linear Variable Differential Transformers (LVDT). The tensile strength, ductility, toughness development, and multi-crack performance of WFRC were obtained as a function of fabric type and aging. The effects of aging on tensile properties are discussed separately for each fabric type. Polyester woven fabric-reinforced composites were found to be superior to flax WFRC in terms of several mechanical properties at all ages. The substitution of diatomite further improved the tensile performance of the polyester woven fabric-reinforced composites. The fabric-matrix interface densification role of diatomite was determined by SEM/EDS line analysis. Evidence of a pozzolanic reaction between portlandite and diatomite was obtained through microstructure studies. Carbon emission analysis revealed that equivalent CO2 emissions could be reduced using diatomite in woven fabric reinforced composites. However, diatomite substitution caused a cost increasing effect.

Enhancing Polybutylene Terephthalate (PBT) Composites: A PROMETHEE-Based Comparative Study of Reinforcement Materials

Polybutylene terephthalate (PBT) composites hold significant potential across various industrial applications due to their desirable mechanical, thermal, and electrical properties. In this study, we utilized the PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluations) method to evaluate six alternative reinforcement materials for PBT composites: Glass Fibers (GF), Carbon Fibers (CF), Natural Fibers (NF), Carbon Nanotubes (CN), Nano-clay Particles (NP), and Aramid Fibers (AF). The evaluation parameters considered were Tensile Strength (MPa), Flexural Strength (MPa), Thermal Conductivity (W/mK), Electrical Conductivity (S/m), and Cost ($). Through comprehensive analysis, Carbon Nanotubes emerged as the top-ranked reinforcement material, exhibiting exceptional performance across all evaluation parameters. With high Tensile Strength, Flexural Strength, and Thermal Conductivity, combined with significant Electrical Conductivity, Carbon Nanotubes demonstrated their suitability for demanding applications. Additionally, while the Cost factor was comparatively higher, its superior performance justifies the investment. Conversely, Natural Fibers received the lowest rank among the alternatives. Despite potential advantages in cost-effectiveness and environmental sustainability, Natural Fibers exhibited inferior mechanical and thermal properties compared to other materials. Their low Tensile Strength, Flexural Strength, and negligible Electrical Conductivity highlight limitations in performance for many industrial applications. This study provides valuable insights for engineers and material scientists in selecting suitable reinforcement materials for PBT composites based on specific performance criteria. The PROMETHEE method offers a systematic approach to decision-making, facilitating informed choices in material selection for diverse applications. Future research could explore optimization strategies and further investigate the properties and potential applications of emerging reinforcement materials for PBT composites.