Glass Fiber Epoxy Research Articles

On the role of temperature in the response of air-backed composites to hydrodynamic loading: An experimental study

Understanding the role of temperature in the dynamic response of composite plates is critical for naval systems operating in extreme environments like the Arctic. Despite the advantages of composite materials in improving corrosion resistance and enabling the customization of material properties to their environment, their behavior at cold temperature, especially under dynamic loading, remains elusive. This research gap hinders the effective use of composite materials in extreme environments. Here, we study the dynamic response of air-backed fiberglass epoxy plates under hydrodynamic loading at room temperature and 4∘C. By employing digital image correlation and particle image velocimetry, we investigated the interplay between fluid–structure interactions and cold temperatures. Our findings reveal the critical role of temperature in shaping the dynamic response of air-backed composites through changes in the stiffness and damping properties. At cold temperature, the plate experiences a larger (smaller) deformation in the initial (latter) phase of the dynamic response. Furthermore, we observed a pronounced coupling between the structural response and the flow physics, with peaks of the hydrodynamic loading synchronized with the peak deflections. Our results underscore the importance of considering temperature in the design of naval systems for extreme environments, providing key insights into fluid–structure interactions at cold temperature.

Interlaminar fracture properties of UV and plasma‐treated glass fiber epoxy composites

AbstractDespite the low density and high specific strength properties, the fiber‐reinforced composites are characterized by a relatively low interlaminar fracture toughness and their ultimate properties are strongly affected by the fiber matrix adhesion. This study aims to investigate the influence of fiber surface treatments, such as UV and atmospheric plasma, and of the interfacial shear strength, on the flexural properties and Mode I interlaminar fracture toughness of glass fiber epoxy composites. The vacuum‐assisted resin infusion technique is used for the composite fabrication. Scanning Electron Microscopy analysis is used to observe and to explain the changes in the morphology of the fibers after surface treatment. Remarkably, the results showed an overall reduction in the mechanical properties. The interfacial shear strength values of the UV and plasma‐treated samples were reduced by 34.9% and 49.5% respectively. The flexural strength was reduced by 7.9% and 5.9% respectively. The Mode I fracture toughness values for the UV and plasma‐treated samples were also reduced by 49.8% and 62.2% respectively.Highlights UV and plasma treatments were performed on glass fibers to improve performance. Push‐out tests were carried out to evaluate fiber/matrix adhesion. An aerospace grade epoxy resin curing in thermal press‐clave was used. Mechanical tests related Interfacial Shear Strength to composites performance.

Mechanical properties investigation of hybrid TI3C2TX MXene and carbon nanotube reinforced glass fiber epoxy composites

Mechanical properties investigation of hybrid TI3C2TX MXene and carbon nanotube reinforced glass fiber epoxy composites

Adhesive-capable film materials for PCM

This paper considers the possibility of joining layers of polymer composite materials (PCM) with adhesives based on chemically modified polyethylene. The adhesive strength between epoxy fiberglass and adhesives (various ethylene copolymers) was investigated. The influence of temperature and pressure on the adhesion between materials has been studied.

Effect of the Glass Fiber Orientation on Mechanical Performance of Epoxy based Composites

Composites are one of the most advanced and adaptable engineering materials. The strength of any composite depends upon volume/weight fraction of reinforcement, orientation angle and other factors. The present work focuses on the determination of the mechanical properties of pure epoxy and unidirectional glass fiber reinforced epoxy. Nowadays, glass fibers are being used in several engineering applications like electronics, aviation, automobile, sport industry etc. Glass fibers are having excellent properties like high strength, flexibility, stiffness, and resistance to chemical attack. With an increase in the content of unidirectional glass fiber volume the properties of unidirectional glass Fiber Reinforcement Polymer (GFRP) composite were improved. It may be used in different forms like chopped, woven mat, short fibers and long fibers etc. Each type of glass fiber has unique properties and is used for different applications. The mechanical and thermal properties of various polymer composites reinforced with glass fibers when subjected to mechanical loading have been studied and reported.

Enhancing wear resistance, mechanical properties of composite materials through sisal and glass fiber reinforcement with epoxy resin and graphite filler

This study investigates the mechanical and wears properties of sisal and glass fiber-reinforced epoxy composites with graphite as filler material. We assessed the mechanical properties of the hand-layup-fabricated composite materials, including hardness, tensile strength, flexural strength, and impact strength, by ASTM standards. We also performed wear evaluations using a pin-on-disc apparatus. The results showed that the weight fractions of sisal fiber, glass fiber, graphite, and epoxy resin significantly affected the mechanical properties of the composites. In contrast to composites reinforced with individual fibers, hybrid composites exhibited enhanced mechanical properties. The optimized compositions showed improvements in tensile, flexural, impact, and hardness properties. The wear analysis revealed that a variety of factors, including the weight percentage of reinforcement, sliding velocity, load, and sliding distance, had an impact on the composites' wear resistance. The SEM images provided significant insights into the composite material's micro structural characteristics and failure mechanisms. In general, this research showcases the potential of graphite filler-reinforced sisal and glass fiber epoxy composites for use in applications that demand exceptional abrasion resistance and mechanical strength. Further refinement of the composition and processing methodologies could lead to the development of composites tailored to specific application demands.

Non-destructive health monitoring of glass fibre epoxy composites under fatigue loading using electrical resistance change method

ABSTRACT This study investigates the effect of stress amplitude on the damage sensing characteristic of glass fibre reinforced (GFRP) composites under fatigue loading using the electrical resistance change (ERC) method. The electrical conductivity of GFRP composites was achieved by incorporating 0.3 wt.% multi-walled carbon nanotubes (MWCNTs) into epoxy resin by ultrasonication method. In-situ electrical resistance measurements during fatigue tests of MWCNT-filled GFRP (MWNCT/GFRP) composites were conducted at two different stress amplitudes, S = 0.6 and S = 0.5. The average stiffness losses at failure were observed as 28% and 25% for S = 0.6 and S = 0.5 respectively. The corresponding ERC ratios at failure were found as 153% and 59% for S = 0.6 and S = 0.5, respectively. A two-parameter Weibull analysis, based on the ERC ratios corresponding to 40%, 60%, 80%, and 100% (failure) fatigue life, was implemented to establish reliability curves at the two stress amplitudes. The ERC ratios at failure with a 95% reliability for S = 0.6 and S = 0.5 were determined as 64% and 23%, respectively. Finally, the remaining fatigue life and the stiffness loss of composite specimens at the ERC ratios corresponding to various Weibull reliability were found for both stress amplitudes.

Mechanical and ballistic studies of boron carbide filler reinforced glass fiber composites

AbstractOwing to the outstanding properties of boron carbide (B4C) particles, material researchers have shown potential in filler‐reinforced polymer composites. The present work studied the implication of B4C fillers on the mechanical and ballistic properties of glass fiber epoxy reinforced composites. Two different weight percentages of 2 and 4 wt% B4C fillers were used to modify the epoxy resin. The composite samples with glass fabric woven were made through compression molding. The results show that the tensile, flexural, interlaminar, impact strength and hardness of glass fiber composite were improved by addition of 2 wt% of B4C. The high‐velocity ballistic tests were conducted on the unfilled and B4C filler‐reinforced composites using a 9 mm parabellum projectile with an initial striking of 372 ± 15 m/s. The least back face signature (BFS) and highest specific energy absorption (SEA) were observed for 2 wt% B4C filler composite. Adding B4C filler enhanced matrix toughening and interfacial bonding between fiber and matrix. Matrix cracking and fiber breakage result in the least ballistic resistance for unfilled composite. Fracture behavior was studied on tensile, impact, and ballistic‐tested samples using scanning electron microscopy. The fractured surfaces of filler‐reinforced composite demonstrated good interfacial bonding, matrix hardening, and fiber pullouts.Highlights The addition of B4C with epoxy up to 2 wt% improves the mechanical and ballistic properties of the composites. The least back face signature and highest specific energy absorption were observed for 2 wt% B4C filler composite. B4C filler enhanced matrix toughening and interfacial bonding between fiber and matrix. Failure of unfilled glass fiber composites is a combination of matrix cracking, fiber pullout, and interface debonding.

Behavior of Composites Made of Quadriaxial Glass Fiber Fabrics and Epoxy Resin under Three-Point Bending.

This paper presents experimental results from three-point bending tests for a composite made of quadriaxial glass fiber fabrics and an epoxy resin. Two composites were tested, one with 8 layers and the other with 16 layers; both had the same matrix (the epoxy resin). Tests were carried out, using five different test rates from 10 mm/min to 1000 mm/min. The following parameters were recorded and calculated: Young's modulus, flexural stress, flexural strain, energy, force, and all four for the first peak. The experimental data reveal no sensitivity for these materials based on the test rates, at least for the analyzed range; but, the characteristics for the thicker composite, with 16 layers of fabric, are slightly lower than those for the thinner composite, with 8 layers. The results pointed out that, for the same thickness of composite, certain characteristics, such as stress at the first peak, the flexural modulus, strain at the first peak, and energy at the first peak, are not sensitive to the test rate in the range 10-1000 mm/min. The energy at the first peak is double for the 16-layer composite compared to the 8-layer composite, but the specific energy (as energy on cross-sectional area) has close values: 103.47 kJ/m2 for the 8-layer composite and 106.51 kJ/m2 for the 16-layer composite. The results recommend this composite for applications in components with resistance to bending or for low-velocity impact protection.

Study on the Wear Behaviour of Aluminium foam Reinforced Glass Fibre Epoxy Composites

Hand layup was used to fabricate the glass fibre reinforced aluminium foam epoxy composites in this study. On the manufactured materials, dry sliding wear experiments were performed. The effect of wearprocess parameters such asapplying load (kg), speed (m/s), and sliding distance (m) on specific wear rate (Ws) was investigatedand the obtained results were compared with neat glass fibre reinforced epoxy composite in this work. The outcome of these results showed that specific wear rate (Ws) of glassfibre epoxy composite containing aluminium foam decreased as compared with neat glass fibre reinforced polymer composites. Experimental results showed that a minimum wear rate of 10.1 �m was attained for the sliding velocity (1.5 m/s), Applied load (2 kg), and sliding distance (1000 m) in the fabricated composite laminates. It was observed thatthe resistance to wear in glass fibre reinforced aluminium foam composite was mainly due to the bond strength between aluminium foam and epoxy.

Enhancing GFRP fatigue durability for chassis component applications through glass fiber coupling variation

As the landscape of mobility trends continues to evolve, concerted efforts have been made to incorporate Carbon Fiber Reinforced Plastic (CFRP) into automotive components. However, the substantial increase in cost relative to the achieved weight reduction has limited its widespread adoption. Consequently, research endeavors have focused on exploring alternative composite materials, adapting fibers such as glass fibers, natural fibers, and recycled fibers, to reduce the cost of composite components. Of particular interest in the automotive industry is the utilization of Glass Fiber Reinforced Plastic (GFRP) in chassis components like leaf springs. Nevertheless, the development of GFRP leaf springs encounters a significant challenge related to the adhesive strength at the interface between epoxy resin and glass fibers, which is crucial for enhancing fatigue durability. While glass fibers were traditionally paired with unsaturated polyester or vinyl ester matrices, the pursuit of improved durability has led to the adoption of epoxy matrices. Regrettably, this transition has not consistently yielded the expected gains in interfacial adhesion.In light of these challenges, this study systematically compares the interfacial adhesion strength and fatigue endurance performance. For comparison, two coupling agents widely used commercially, amino silane and epoxy silane, were selected. Glass fibers treated with each coupling agent were purchased commercially, and glass fiber-reinforced plastic (GFRP) specimens were fabricated using the HP-RTM (High-Pressure Resin Transfer Molding) method. Static property evaluations and fatigue durability assessments were conducted using the fabricated specimens. The results showed that when epoxy silane was used as the coupling agent, the interlaminar shear strength (ILSS) increased by approximately 7 %. Furthermore, SEM(Scanning Electron Microscopes) analysis confirmed a significant enhancement in interfacial adhesion, providing support for the ILSS evaluation results. Consequently, the fatigue durability performance improved by approximately six-fold. This confirms that the improvement in interfacial adhesion due to the change in coupling agents led to enhanced fatigue durability performance.

Investigating the impact of cross-sectional area on the crushing characteristics of axially-loaded hemispherical composite shells

The research focus has shifted towards lightweight structures with high energy absorption capabilities due to advancements in automotive safety technology. This study specifically investigates the impact of cross-sectional area on the energy absorption characteristics of hemispherical composite shells. The experimental phase involves characterizing a glass fiber epoxy composite, followed by the manufacture of hemispherical composite shell specimens with varying cross-sectional areas. These specimens undergo quasi-static axial compressive loading, and the energy absorption parameters are analyzed. The results indicate a significant influence of the composite cross-sectional area on the crushing behavior of hemispherical shells, with a observed decrease in specific energy absorption as the cross-sectional area increases. Additionally, a 3D Finite Element (FE) model is created using ABAQUS FE code to numerically simulate the crushing process. The model’s predictions are compared and validated against experimentally measured values, demonstrating a satisfactory correlation.

Effect of synergistic action of anodising and graphene on the mechanical properties of fibre-reinforced metal laminates

Fibre reinforced metal laminates (FMLs) are widely used in various fields due to their excellent properties. However, the weak interlayer properties of FMLs limit their applications. In this paper, the interlayer properties of FMLs are enhanced by anodising the 2024-T3 aluminium alloy layer in FMLs or by epoxy matrix modification of graphene nanoplatelets (GNPs). The effect of both synergistic impacts on the interlayer properties of most FMLs is investigated. The FMLs were manufactured using the wet lay-up technique using 2024-T3 aluminium alloy, E51 epoxy and EW100 glass fibre. The results showed that the type I fracture toughness, tensile strength, flexural strength, interlayer shear strength and single layer shear strength of FMLs after anodic oxidation treatment were increased by 406.4%, 10.3%, 18.3%, 42.6% and 28.3%, respectively, compared with those of pure FMLs. The type I fracture toughness, tensile strength, flexural strength, interlayer shear strength and single layer shear strength of the GNPs-modified FMLs matrix were increased by 280.4%, 3.7%, 6.8%, 34.5% and 19.1%, respectively, compared with those of pure FMLs. Moreover, the synergistic effect of FMLs indicates that the simultaneous anodic oxidation and GNPs modification of FMLs can lead to the best mechanical properties of FMLs. Microscopic images and schematics illustrate the toughening mechanism of anodising and GNPs, including the enhancement of aluminium/resin interface and fibre/resin interface and the enhancement of resin matrix properties.

Preparation and properties of Al2O3 modified epoxy-glass fiber composites

The present study intends to use Al2O3 as thermal conductivity filler, epoxy resin as matrix, and glass fiber as reinforcement material, and prepare Al2O3 modified epoxy-glass fiber composite materials through vacuum diversion flow and hand paste molding. By changing the amount of Al2O3, performance tests and comparison are conducted. The results show that when the content of Al2O3 filler is 2 %, the comprehensive mechanical properties are the best, the thermal conductivity is increased by about 20 %, the specific heat capacity is increased by about 30 %, and the combustion time is also increased by 10 s.

Towards sustainable composites: Evaluation of mechanical properties, erosion behavior and applications of natural fiber-epoxy composites

Sustainable production and consumption, carried to materials and engineering applications, translates to a need for recyclable, reusable, and/or biodegradable materials. With its lower cost, lighter weight, and less carbon footprint compared to traditional glass and carbon fiber composites, natural fiber-reinforced composites are drawing more attention from the scientific community and the industrial sector. The natural fiber’s high variability and relatively inferior mechanical properties necessitate comprehensive characterization for accurate evaluation of their properties and fitness for different applications. In this research, various locally grown natural fibers (Flax, Jute, and Luffa) were sourced, characterized, and used to synthesize natural fiber-reinforced epoxy composites. The tensile, flexural, impact properties, and erosion resistance of the composites was evaluated. Compared to the other natural fiber composites, the Jute-Epoxy composite achieved the highest tensile strength and tensile modulus with 31 MPa and 4.8 GPa respectively; Jute-Epoxy also achieved the highest flexural strength and flexural modulus, with and 60 MPa and 2.4 GPa respectively. This superior mechanical performance is due to the relatively high strength of the Jute fiber and its high adhesion to the matrix, which is supported by fractographic evidence. Luffa-Epoxy composites in general had the lowest properties of all the tested materials. The erosion test results showed that the Jute-Epoxy composites had the highest erosion resistance of all the tested materials; with 30% more erosion resistance compared to glass-fiber epoxy composites. Based on the experimental results of the investigation and similar previous research, the current and potential applications of natural fiber composites were discussed.

Investigation of substrate materials laminated CPW-Fed patchantennas: Opportunities and challenges

This article investigates the design of antennas fed by coplanar waveguide (CPW) utilizing different substrate materials and techniques. The article illustrates the impact of several materials such as FR-4, Rogers, Arlon, etc on electrical properties such as impedance bandwidth (IBW), reflection coefficient (|S11|), and gain. The article also examines the effects of design approaches such as including stubs, slots, arrays, etc on antenna |S11| parameters. The resonance frequencies (fr) of the suggested antennas may be modified by manipulating the electrical dimension, the dielectric constant of the substrate materials, and their respective thicknesses. The structure of the Flame-Retardant fiberglass epoxy (FR-4) proposed antenna covers anoperating frequency range of 3.3 to 10.1 GHz. It can operate at six distinct frequency bands, making it appropriate for applications including C-band (4-8GHz), X-band (8-12GHz), 5G (3.5-6.0GHz), and 6G (7-20GHz). The antenna designed and simulated using computer simulation software (CST) electromagnetic simulator.

High-performance hybrid glass fibre epoxy composites reinforced with amine functionalised graphene oxide for structural applications

Glass fibre-reinforced epoxy (GFRE) composites have had limited use as structural components in industrial applications (e.g., oil and gas, aerospace and civil infrastructure). The use of nanomaterials, such as graphene, has been explored recently to enhance the mechanical and long-term properties of GFRE to realise their full potential and increase their usage. This study evaluated the tensile, creep, and fatigue behaviour of amine-functionalised graphene oxide (fGO) modified glass fibre/epoxy laminate composites. A spray coating technique was used to coat the fGO particles onto the glass fibre surface, and epoxy composite laminates were manufactured using the vacuum resin infusion method. Creep and fatigue testing was performed under a load-controlled mode in tension. Adding fGO within the composites significantly improves the static, creep, and fatigue properties of the fGO-GFRE composites at both room and elevated temperatures. It is shown that fGO acts as a barrier to microcrack initiation and restrains the macrocrack propagation during cyclic loading under elevated temperatures in the GFRE composites. These factors, therefore, prevent the early delamination of the matrix and fibre interface during cyclic loading, which explains the fatigue life extension observed in the fGO-modified composites. With 0.05 wt% fGO, the fatigue life of the fGO-GFRE composites was extended by 8× and 30× at a maximum stress of 124 and 151 MPa respectively, in a 90 °C environment compared to the control GFRE composites. While the creep life compared to the control increased by 63×, 103× and 159× with 0.25 wt%, 0.5 wt% and 1 wt% fGO, respectively. These enhancements are attributed to the large surface area, high stiffness, and functional groups present, which provide a stronger bond between the composite phases. These features help restrict the mobility of the polymer chain during the creeping load and act as barriers to fatigue crack propagation, enhancing the composite’s durability. The nanocomposites produced display attractive properties for many possible industrial applications where improved performance is needed while maintaining a minimum cost.

Mechanical properties and damage development in glass-fiber epoxy laminates subjected to tensile loading at sub-zero temperatures

In various structural applications polymer composites are exposed to sub-zero and even cryogenic temperatures which may initiate of microstructural damage. To anticipate these events, one needs to understand the behavior of composites in a sub-zero environment. This study focuses on damage initiation and accumulation, and its influence on the properties of cross-ply glass fibers epoxy composites at sub-zero temperatures. The effect of bromine modification of epoxy, and the dissolution in an organic solvent on the mechanical performance of the produced composite is also investigated. To evaluate the influence of a sub-zero environment on the mechanical performance of glass fiber epoxy laminates, tensile tests in a sub-zero environment of unconditioned specimens were carried out. The quasi-static tensile tests were performed to measure the elastic modulus of the composites while loading-unloading experiments were performed to monitor the initiation (and accumulation) of microstructural damage and its influence on the stiffness of glass fiber epoxy laminates. The results of cryogenic damage and fracture in the laminates are discussed with a focus on the degradation of properties of glass fiber crucial for their use in structural applications: strength and stiffness.

Statistical analysis to examine the influence of thermal aging on hybrid glass epoxy polymer composites with fillers of multi‐walled carbon nanotubes

AbstractE‐glass fibers are widely preferred due to ease of processing and its low cost, which has substantial scope in the fields of electronics and electrical insulation applications. Because of its low strength and corrosion resistance, use of E‐glass fibers is limited in aerospace and automotive applications. There is a need for enhancing the properties of the composite to overcome such limitations. Therefore, an attempt is made to introduce multi‐walled carbon nanotubes (MWCNT) as fillers into E‐glass fibers to meet the industry needs. In the current study, woven glass fiber of 5 layers and multi‐walled nano carbon fillers of 2, 4 and 6 by wt%, LY556 epoxy resin, and HY951 hardener were used to prepare 4 different type of composites along with the neat epoxy glass fiber reinforced polymer composites (GFRP). The hand‐layup route was used in the composite preparation due to its low cost, technological feasibility, and simple process setup. The developed samples were characterized for mechanical properties via tensile, flexural and impact tests. Tribological characteristics were performed by air jet erosion test. Chauvenet's criterion is applied for identifying the outliers (if any) from the data of repeated test properties. Taguchi's (orthogonal array) is selected for obtaining optimal hybrid composite, which yield better mechanical properties. Empirical relations are developed for the material properties in terms of process variables. The sample (4 wt% MWCNT) exhibited enhancement of 17.27% in tensile strength, 6% of impact strength and 7.3% of flexural strength when compared with neat epoxy GFRP. This hybrid composite is considered for thermal aging and observed at 60°C, 8% increase in tensile, 7% increase of impact and 15% in flexural strength due to the precipitation on carbon nano tubes along the gain boundaries. The present study recommends 4% MWCNT fillers in developing hybrid glass epoxy polymer composites for use in aerospace, automotive and civil construction industries due to economic and technological feasibility.Highlights Utilize low‐cost E‐glass fibers in electronics and electrical insulation applications. Improve composite properties for aerospace and automotive industries. Develop hybrid glass epoxy composites with 2 to 6 wt% MWCNT fillers. Examine wear characteristics under air jet erosion and study the impact of thermal aging on mechanical properties. Apply Chauvenet's criterion for outlier identification in measured properties datasets.

Intrinsic flame-retardant epoxy resin composite containing schiff base structure with satisfied flame retardancy and mechanical properties

To solve the non-renewable and flammability of traditional epoxy composites, a new type of intrinsic flame-retardant epoxy (VH/GF) composite was fabricated from vanillin-based epoxy resin (VH) and glass fibre (GF). The T5% of VH/GF was higher than that of DGEBA/GF, and CY800 of VH/GF reached above 84 wt%. VH/GF obtained a limiting oxygen index as high as above 90 % and passed UL-94 V-0 rating. Compared with DGEBA/GF, the total heat release, total smoke production, maximal smoke density of VH/GF reduced by more than 72 %, 91 % and 81 %, respectively. The physical barrier of glass fibre and excellent char formation ability of VH endowed VH/GF composite with good condensed phase flame-retardant effect. When the mass ratio of matrix and glass fibre was 5:5, the storage modulus and glass transition temperature of VH/GF were 6.34 GPa and 205 °C, and its tensile strength and elongation at break were 348.36 MPa and 4.01 %. This work provides new research insights for bio-based epoxy resin in high-performance fire safety composites.