Glass Fiber Composites Research Articles

Local elasticity assessment of unidirectional fiber-reinforced polymer composites through impulse excitation and machine learning

This study presents a novel methodology that integrates the Impulse Excitation Technique (IET) and machine learning (ML) to predict local elastic properties within isolated regions of unidirectional polymeric composite plates. The proposed model incorporates fiber volume and plate thickness as input parameters and leverages the first resonance frequencies of the local region at different fiber orientations, thus accounting for the composite’s anisotropy. Regression results from the deep neural network (DNN) model demonstrate robust prediction performance across all output targets in both testing and training datasets, with R2 coefficients surpassing 0.9. The model exhibits particularly strong performance in predicting Young’s moduli. Additionally, each output objective shows sensitivity to a unique balance of input parameter weight factors for achieving optimal ML predictions. Moreover, a parabolic trend in the weight factors of fundamental frequencies at different orientations is observed as the rigidity of composites changes. Lastly, a comparative study between carbon-fiber and glass-fiber composites highlights the variations in fiber volume and elastic constants, emphasizing the effectiveness of the proposed model in accurately predicting material properties.

Mechanical, machinability and water absorption properties of novel kenaf fiber, glass fiber and graphene composites reinforced with epoxy

This paper aims to fabricate a novel kenaf fiber, glass fiber, graphene composite reinforced with epoxy, and to study its water absorption, mechanical and machining properties. Natural fiber composites seek numerous applications nowadays due to its high strength is to weight ratio, high impact resistance, thermal stability, and recyclability. The literature study on natural fiber composites indicates lack of research on Kenaf fibers reinforced with E-glass fibers in conjunction with 0.5% and 1.0% of graphene. Hence, this research focuses on Kenaf fiber with percentage composition of graphene was varied as 0.5%, and 1.0%, by weight of the holding matrix and with/without incorporation of glass fiber. Suitable surface modifications were done by treating natural fibres by 0.5% NaOH for better adhesion of fibre and epoxy resin. Sonication and Cetyl trimethyl ammonium bromide (CTAB) treatments were also done to realize the fine scattering of graphene in the epoxy matrix in order to achieve better mechanical behaviour. Moulds were prepared as per D-638 ASTM standards. The treated fibres were then arranged in the mould by the conventional hand layup technique. The main objectives of this study are to conduct tensile, flexural, Impact, water absorption, machinability, and FTIR test. Result shows that the incorporation of graphene in natural fiber composites showed an increase in tensile strength, flexural strength, and water absorption properties by 27.7%, 53%, and 15% on average, respectively. The composites used in this research find their use in potential applications such as defence, biomedical aids, automobiles, packaging, actuators, etc. These often generate great interest, whenever there is a demand for fabricating lightweight and high strength material.

On the Hydrodynamic and Structural Performance of Thermoplastic Composite Ship Propellers Produced by Additive Manufacturing Method

In the marine industry, the search for sustainable methods, materials, and processes, from the product’s design to its end-of-life stages, is a necessity for combating the negative consequences of climate change. In this context, the lightening of products is essential in reducing their environmental impact throughout their life. In addition to lightening through design, lightweight materials, especially plastic-based composites, will need to be used in new and creative ways. The material extrusion technique, one of the additive manufacturing methods, is becoming more widespread day by day, especially in the production of objects with complex forms. This prevalence has not yet been reflected in the marine industry. In this study, the performances of plastic composite propellers produced by the material extrusion technique is investigated and discussed comparatively with the help of both hydrodynamic and structural tests carried out in a cavitation tunnel and mechanical laboratory. The cavitation tunnel test and numerical simulations were conducted at a range of advance coefficients (J) from 0.3 to 0.9. The shaft rate was kept at 16 rps. The thrust and torque data were obtained using the tunnel dynamometer. Digital pictures were taken to obtain structural deformation and cavitation dynamics. The structural performance of the propellers shows that an aluminum propeller is the most rigid, while a short carbon fiber composite propeller is the most flexible. Continuous carbon fiber composite has high strength and stiffness, while continuous glass fiber composite is more cost-effective. In terms of the hydrodynamic performance of the propellers, flexibility reduces the loading on the blade, which can result in thrust and torque reduction. Overall, the efficiency of the composite propellers was similar and less than that of the rigid aluminum propeller. In terms of weight, the composite carbon propeller containing continuous fiber, which is half the weight of the metal propeller, is considered as an alternative to metal in production. These propellers were produced from a unique composite consisting of polyamide, one of the thermoplastics that is a sustainable composite material,, and glass and carbon fiber as reinforcements. The findings showed that the manufacturing method and the new composites can be highly successful for producing ship components.

Mechanical and tribological characteristics of glass fiber and rice stubble-filled epoxy-LD sludge hybrid composites

Mechanical and tribological characteristics of glass fiber and rice stubble-filled epoxy-LD sludge hybrid composites

Development and characterization of glass fiber composites impregnated with limestone powder and bagasse fiber

Abstract Materials development is essential for all industries to meet the current demands Limestone powder (LS), coconut shell fiber (CSF) and sugarcane bagasse fiber (SBF) were impregnated in a laminated glass fiber polymer matrix. The fiber to matrix ratio is 50 %, while SBF and CSF start replacing natural fibers at a rate of 5–15 %, and LS is always 5 %. The proposed fiber-reinforced composites were manufactured by compression molding (CMM) and the test samples were cut according to the ASTM for tensile, impact, moisture, scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermogravimetric (TGA) tests. The results showed that the strength of the materials is influenced by the impregnation of the fibers into the matrix phase. Impregnation of natural fibers in glass fiber composite structures at 10–15 % loading demonstrated a weight saving of 7–8 %, tensile strength ranging from 330 to 350 MPa, maximum moisture absorption of 3.4 g, and thermal stability around 300 °C. Addition of limestone powder resulted in improved bonding ability, better surface finish, and reduced porosity, as demonstrated by SEM analysis.

PROSPECTIVE DIRECTIONS OF THE DEVELOPMENT OF BIOACTIVE GLASS FIBERS FOR MEDICAL APPLICATION

The urgency of the development and use of glass fibers for the creation of microfiber dressings for the treatment of chronic wounds in combat conditions has been determined. The availability of such materials is especially important in the conditions of hostilities, which are characterized by the need for quick resuscitation of the wounded and the provision of emergency aid on the battlefield. The use of such materials will save life, shorten the rehabilitation period, and speed up the recovery of the military and civilian population. An analysis of the scientific and technical literature on the composition and properties of bioactive glass fibers for medical use was carried out. The compositions and properties of glass fibers for various purposes were analyzed and their possibility of use in the development of bioactive glass fibers for medical use was established. The selection of the compositions of bioactive glass fibers with a prolonged biocidal effect for the rapid healing of wounds and the restoration of bone tissue is substantiated. The mechanism of action of biocidal components and boron ions in the composition of bioglasses on the ability to inhibit the negative effects of pathogenic microorganisms was analyzed. The use of boroaluminophosphate glass fibers for the manufacture of effective dressings for the treatment of wounds in crisis situations in combat conditions will increase the percentage of survival and reduce the duration of treatment due to the direct action of cations and anions of the materials in vivo. The main theoretical principles of the creation of bioactive boroaluminophosphate glass fibers, modified with group II metal cations, which will be characterized by the presence of a strengthened surface layer, and characterized at the same time by high biocompatibility, biocide with prolonged action and non-toxicity, have been determined. The introduction of domestically developed bioactive glass fibers into medical practice will significantly increase the competitiveness of domestic medical materials, as well as ensure defense capability and safety, and contribute to the stabilization of the market in the conditions of sustainable development of the state.

Shape parameter of Weibull size statistics is a potential indicator of filler geometry in SiO2 reinforced polymer composites

In a previous study [Physica A, 625 (2023), 129026], a relationship between the filler size distribution and the filler geometry of SiO2 particle reinforced polymer composites has been reported. It has been experimentally demonstrated that the size of hollow and solid SiO2 particles disperse in polymer matrix follows Weibull statistics with shape parameter at 2 and 3, respectively. This mechanism has not yet been verified in the one-dimensional (1D) case. In this paper, we study the length distribution of glass fibers in polymer composites. Our results show that the previous theory still holds for the 1D case. Thus, shape parameter of Weibull size statistics could be a potential indicator of filler geometry in SiO2 reinforced polymer composites. This interesting mechanism can be explained by the scaling nature behind the Weibull statistics. Our study has thus shed new light on the evolution of filler geometry during the fabrication process of polymer composites, and should be useful for the related fields.

Evaluation of the mechanical characteristics of epoxy resin hybrid composites reinforced with date palm stem fibre and glass fibre

This study investigates the mechanical properties of epoxy resin hybrid composites reinforced with date palm stem fibres (DPSF) and glass fibres (GF). Natural fibres like DPSF offer numerous advantages, including low cost, renewability and biodegradability, making them environmentally friendly alternatives to synthetic fibres. GF, on the other hand, is well-known for its high strength and lightweight properties, making it ideal for various industrial applications. In this research, DPSF and GF were combined to create hybrid composites, aiming to enhance mechanical properties and reduce production costs compared to pure GF composites. The study involved the preparation of DPSF and the fabrication of composites using a hand lay-up approach with varying fibre proportions, followed by mechanical testing that included impact, flexural, tensile test and as well as a water absorption test. The results show that both the flexural and tensile strengths of a composite with epoxy resin containing 10 wt%DPSF and 10 wt%GF improved significantly, resulting in a tensile strength of 17.75 MPa and a flexural strength of 48.13 MPa, along with a favourable reduction in water absorption. The impact strength was significantly increased by the optimal integration of a composite with epoxy resin containing 20 wt% DPSF and 10 wt% GF. These findings suggest that the hybrid composites demonstrate enhanced mechanical properties, revealing the combined benefits of DPSF and GF. This study underscores the potential of DPSF-GF reinforced composites as a cost-effective and mechanically strong alternative to conventional GF composites.

A novel thermoplastic material: Pre‐polymerized PMMA liquid resin and continuous glass fiber‐reinforced composite initiated by benzoyl peroxide/N,N‐dimethylaniline

AbstractThermoplastic PMMA was rarely exploited in continuous fiber‐reinforced composites due to its viscous high‐temperature molten fluid as well as pessimistic wettability into fiber fabric. Redox‐active polymerization is a green route to develop a new liquid PMMA resin at room temperature to provide an in situ curing with the advantages of energy saving and consumption reduction. In this paper, BPO/DMA was adopted as a redox initiator pair, and the effect of MMA:BPO:DMA ratio on curing time, Mn, Tg, and mechanical properties of PMMA were systematically studied. When the ratio of MMA:BPO:DMA is 200:1.2:1, PMMA‐200 achieved optimistic mechanical properties at 20°C (tensile strength, 64.7 MPa; tensile modulus, 3352 MPa; bending strength, 125.3 MPa; bending modulus, 3023 MPa). Moreover, the mechanical properties were further improved at low temperatures. The maximum tensile strength and tensile modulus were up to 97.43 and 4297 MPa (−40°C) respectively. The tensile strength (0°, 1103 MPa; 90°, 52.3 MPa) and tensile modulus (0°, 47.5 GPa; 90°, 14.2 GPa) of glass‐fiber‐reinforced PMMA composite at 20°C were found to be comparable with epoxy resin‐based composites and even higher at lower temperature. In summary, redox‐initiated PMMA and its fiber‐reinforced composites are promising thermoplastic materials as new lightweight alternatives.Highlights Preparation method of PMMA resin and glass fiber composite. Research on the mechanical properties, molecular weight, glass transition temperature, curing time, etc. of PMMA resin. Testing of mechanical properties of PMMA glass fiber composites at room temperature and low temperature. Current applications and prospects of PMMA glass fiber composites.

Hygrothermal aging and recycling effects on mechanical and thermal properties of recyclable thermoplastic glass fiber composites

Hygrothermal aging and recycling effects on mechanical and thermal properties of recyclable thermoplastic glass fiber composites

An Experimental Investigations on Design and Weight Optimization for a Light Motor Vehicle (LMV) Drive Shaft Using a Composite Material Aluminum and Glass Fiber (Al + GF)

Aluminum is primarily used in Metal Composites because of its lighter weight and higher strength. Glass fibers are wound around an aluminum shaft to create the composite. ANSYS results determine the relative amounts of aluminum and Eglass fiber in each shaft. The purpose of this study is to use a torsion test to evaluate the mechanical performance of a composite shaft composed of aluminum and glass fiber. The results are carefully examined for different combinations of glass fiber layers and aluminum layers. When the weight proportion of aluminum in the composite increases, the mechanical properties of the composites improve.

Green Innovation: Kenaf Fiber as a Sustainable Filler in Composites

Kenaf fiber has recently gained significant attention as a reinforcement in composite materials across various industries due to its excellent mechanical properties, ease of manufacturing, and natural biodegradability. This brief review examines the physical and chemical properties of kenaf. The high cellulose content of kenaf composites enhances their mechanical and thermal properties. Additionally, several previous studies focusing on improving kenaf composites are highlighted. The reinforcement made by using the kenaf fiber shows its potential to replace the glass fiber composite. The review also discusses the applications of kenaf in various industries, as well as the challenges faced by the kenaf industry in Malaysia and globally. Finally, the review addresses the potential and market demand for kenaf fiber and kenaf seed oil.

MECHANICAL PROPERTIES OF GLASS FIBER AND CARBON FIBER REINFORCED COMPOSITES

The significant potential of glass fiber-based composite materials in aerospace and aviation industries, automotive manufacturing, and medical equipment production is emphasized. It is concluded that glass fiber is much cheaper and less brittle compared to materials like carbon fiber or other plastic fibers, as glass fiber exhibits high resistance to tensile and compressive loads. The main stages of the technological process of composite manufacturing are described, and the key requirements for evaluating the mechanical parameters of glass fiber products are listed. An analysis of the scientific literature has established that the high strength of fiberglass ensures the stability of its thermal conductivity characteristics, making it resistant to environmental influences and aging. The thermal conductivity of fiberglass composites depends on several factors, the most important of which are the type of fiber and matrix, fiber volume fraction, fiber characteristics, control of heat flow, interaction between the matrix and fiber, and operating temperature. It is summarized that the mechanical properties of fiberglass structures depend on a number of factors, the most important of which are: the type of fiber and resin, fiber orientation (aligned, randomly oriented, woven, etc.), and the percentage content of each component.

Effect of high quality hybrid coatings and coating condition on the properties of continuous glass fiber reinforced polypropylene prepreg composites

AbstractDue to the difficulty in infusing resin into interiors of fiber bundles by prevalent pre‐impregnation methods like melt impregnation and the substantial polarity difference between glass fibers (GF) and polypropylene (PP), the application of continuous glass fiber reinforced polypropylene (CGF/PP) composites has been restricted. In this study, a hybrid emulsion is prepared to address the polarity difference through coating process. And further by optimizing coating process parameters, composites glass fibers with excellent performance can be obtained. The study demonstrates that the composite glass fiber with coating amount of 15.34% exhibits good bunching and flexibility. The monofilament tensile strength and interfacial shear strength (IFSS) are increased by 2.53% and 109.74%, respectively compared to the desized glass fiber (GF0). Furthermore, after the hot‐pressing process, the composites glass fiber bundles show fully filled gaps and a completely wrapped surface. This study lays the foundation for producing CGF/PP prepreg composites conveniently, efficiently, and commercially.

Correction to “Investigating the changing dynamics of processing, temperature‐based mechanics, and flame retardancy in the transfer of ammonium polyphosphate/inorganic silicate flame retardants from epoxy resins to glass fiber composites”

Correction to “Investigating the changing dynamics of processing, temperature‐based mechanics, and flame retardancy in the transfer of ammonium polyphosphate/inorganic silicate flame retardants from epoxy resins to glass fiber composites”

Repair overlays of modified polymer mortar containing glass powder and composite fibers-reinforced slag: mechanical properties, energy absorption, and adhesion to substrate concrete

This article aims to investigate the mechanical properties and substrate adhesion of the pull-off method in polymer mortars modified with styrene-butadiene resin polymer (SBR) containing glass powder and composite fiber-reinforced slag. Different mix designs were investigated with and without SBR, taking into account different amounts of glass powder and slag separately and in combination, along with the effect of glass, polypropylene, and steel fibers alone and in combination. The flexural performance and energy absorption of beams retrieved with these layers were also assessed. The results revealed significant differences and increases in the substrate adhesion of the restored modified polymer layers containing SBR compared to the polymer-free repair overlays. Furthermore, an improvement was observed in the adhesion performance of the repair overlay using a combination of slag and glass powder and the glass and polypropylene fiber composite. The highest adhesion was related to the modified polymer mortar design containing composite fibers of glass, polypropylene, and steel with 25% replacement of SBR polymer for 10% glass powder, 10% slag, and 5% slag with 5% glass powder. The adhesion was increased by about 3.74, 3.72, and 3.78 times compared to the repair overlay of the control design. Modified polymer mortars had a higher T150D toughness. Moreover, the energy absorption was significantly improved by the presence of SBR polymer. The highest toughness values were found in the beams restored with modified polymer mortars containing polypropylene, glass, and steel composite fibers with an increase of 48.51%–66.42% compared to the samples without polymer as a result of the pozzolans used in this mix.

In situ assembly enabling adhesive-free bonding of large area electronic sensors to concrete for structural health monitoring

Abstract Cracks developed in concrete infrastructure are one of the primary mechanisms that degrade their structural integrity, which may result in structural failures. Previous research on soft elastomeric capacitors (SEC) has shown their viability for structural health monitoring of structural materials, including concrete, steel, and fiberglass composites. The SEC, or its derivative version with a corrugated geometry termed corrugated SEC or cSEC, is a parallel plate capacitor. Prior work demonstrated that it was possible to directly paint the electrode interfacing with the structural material onto the structure and adhere the rest of the pre-fabricated sensor onto the wet interface, thereby eliminating the need for a joining epoxy. This demonstration was conducted on steel and fiberglass. The study on concrete was left to future work as concrete exhibits a much rougher surface and structure/sensor capacitive coupling, causing a significant amplification in signal noise. This study advances structural health monitoring in concrete applications by investigating the in situ assembly of the SEC on concrete where the carbon black (CB)-based electrode plate of the cSEC is directly painted onto the concrete surface and serves as both the adhesive and electrode for the sensor. A series of free-vibration and compression tests were designed and conducted to evaluate the sensing performance of in situ assembled cSEC compared to that of an epoxy-bonded cSEC. Additionally, the bonding strength of the in situ assembled and epoxy-bonded cSEC is evaluated through a peel test. Results show good strain sensing capabilities of the in situ assembled SEC with an R 2 value of 0.986 and a resolution of 45 ± μ ε . Even though the epoxied cSEC demonstrated a higher bonding strength than the in situ assembled cSEC, the in situ assembled cSEC demonstrated adequate bonding strength for the application. This research contributes to the scientific understanding of sensor adhesion and opens avenues for practical applications in infrastructure monitoring, potentially leading to more resilient and sustainable urban environments.

Dynamic fracture characterization of glass fiber composites reinforced with through-thickness nylon fibers

ABSTRACT A detailed experimental study is performed to investigate the mode-I dynamic fracture initiation toughness of through-thickness Nylon fibers reinforced glass/epoxy composites using a wet electrostatic flocking method. Composites of a double cantilever beam specimen configuration of two different deniers 1.5D and 3D of 0.75 mm long Nylon fibers with two different fiber densities 150 and 300 fiber/mm2 and composites without Nylon fibers (control) are fabricated. The dynamic fracture initiation toughness is investigated by using a modified split Hopkinson pressure bar setup with a novel fixture in conjunction with a high-speed video camera. In addition, rate sensitivity on dynamic fracture initiation toughness is also investigated for control and composites of 1.5D with fiber density of 300 fibers/mm2 as a function of three different rates of dynamic fracture toughness ( G ˙ = 1500, 2010, and 2,150 kJ/m2/s). Results show that for the composite of 3D–0.75 mm Nylon fiber, G IC values reach 0.78 kJ/m2 (110% increase) and 1.3 kJ/m2 (250% increase) at flock densities of 150 and 300 fibers/mm2 compared to the control sample with the lowest G IC value at 0.37 kJ/m2. The same pattern is observed for a 1.5D–0.75 mm configuration at the flock fiber density of 150 fiber/mm2 where G IC value demonstrates a 75% increase compared to control conditions. The dynamic fracture initiation toughness of flocked composites demonstrates significant rate sensitivity.

Flat silk cocoons: A candidate material for fabricating lightweight and impact-resistant composites

The utilization of silk cocoons in the production of lightweight and tough composites has been gaining increasing attention. However, the limited applications of normal silk cocoons (NSC) are attributed to their small size and irregular shape. To overcome this deficiency, flat silk cocoons (FSC) with a similar structure and controllable size were prepared. Next, we systematically characterized and compared the microstructures, morphologies, compositions, thermal properties, and mechanical properties of FSC with NSC. Subsequently, FSC was successfully utilized to fabricate a novel silk fibroin fiber reinforced sericin matrix composite (HPFSC) using a hot pressing method, followed by the analysis of its microstructure evolution, mechanical properties, failure modes, and theoretical modeling. This composite has outstanding mechanical properties including hardness, modulus, and strength. HPFSC has a relatively low density of ~1.3 g/cm3, whose absorbed impact energy can reach a maximum value of 11.1 J/mm, exceeding that of most engineering materials, such as aluminum alloy, ceramics, glass, and carbon fiber composites. The exceptional performance of HPFSC can be attributed to the reduced porosity, enhanced bonding between silk fibroin fibers facilitated by sericin, and their structural transformation. This study offers valuable guidance for the fabrication of lightweight and impact-resistant composites using flat silk cocoons.

Numerical Investigation of the Effects of Impactor Geometry on Impact Behavior of Sandwich Structures

The aim of this study is to examine the impact performance and damage behavior of sandwich composite structures with a core material of aluminum and a facesheet of glass fiber composites using the finite element method. In the study, the effects of impactor shape, impact velocity and number of core layers on peak force, absorbed energy efficiency, maximum displacement and damage deformation were examined. For low velocity impact simulation, progressive damage analysis was performed based on the Hashin damage criterion using the MAT 54 material model in the LS DYNA finite element program. While providing the connection between the core structure and its surfaces, a Cohesive Zone Model (CZM) based on the bilinear traction-separation law was created and examined. At the end of the study, it was determined that the shape of the impactor had a significant effect on impact resistance. Energy absorption efficiency may vary as impact energy changes. However, as the impact energy increases, the energy absorption efficiency increases. It was determined that the largest and dominant damage type for all three impactors was matrix damage.