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Highlights Glass fiber reinforced polymer (GFRP) composites with chopped strand mat (CSM) and woven roving mat (WRM) reinforcements are widely used in high‐pressure piping due to their favorable strength‐to‐weight ratio. However, cyclic loading from vibrations and pulsating forces can induce internal microstructural damage, ultimately leading to performance degradation. A thorough understanding of this damage mechanism is imperative for its mitigation, necessitating a detailed examination. The present study aims to investigate the fatigue response and damage mechanisms in CSM and WRM composites subjected to tension‐tension cyclic loading. Scanning electron microscopy analysis of edge sections revealed the development of perpendicular microcracks in both composites. CSM composites exhibited fatigue cracks parallel to the loading direction and higher levels of parallel interface debonding compared to perpendicular matrix cracks. Finite element analysis of the representative volume element revealed the role of shear stress in the matrix in initiating parallel cracks, thereby explaining the damage initiation mechanism in CSM. These findings highlight the distinct damage mechanisms arising from the differing fiber arrangements in CSM and WRM composites, providing valuable insights for optimizing their performance under cyclic loading conditions. Fatigue response of CSM and WRM was influenced by fiber orientation and weaving pattern. Perpendicular fibers were the most probable fibers to have their interface form a crack. Fatigue cracks parallel to the direction of loading were observed in CSM composites. Quantified the true 3D internal microstructural damages for the first time. [ABSTRACT FROM AUTHOR]

Zinc‐based aqueous batteries (ZABs) are attracting extensive attention due to the low cost, high capacity, and environmental benignity of the zinc anode. However, their application is still hindered by the undesired zinc dendrites. Despite Zn‐surface modification being promising in relieving dendrites, a thick separator (i.e. glass fiber, 250–700 μm) is still required to resist the dendrite puncture, which limits volumetric energy density of battery. Here, we pivot from the traditional interphase plus extra separator categories, proposing an all‐in‐one ligand buffer layer (ca. 20 μm) to effectively modulate the Zn2+ transfer and deposition behaviors proved by in situ electrochemical digital holography. Experimental characterizations and density functional theory simulations further reveal that the catechol groups in the buffer layer can accelerate the Zn2+ reduction reaction (ZRR) through the electron‐donating p‐π conjugation effect, decreasing the negative charge in the coordination environment. Without extra separators, the elaborated system endows low polarization below 28.2 mV, long lifespan of 4950 h at 5 mA cm−2 in symmetric batteries, and an unprecedented volumetric energy density of 99.2 Wh L−1 based on the whole pouch cells. The concomitantly "separator‐free" and "dendrite‐free" conjugation effect with an accelerated ZRR process could foster the progression of metallic anodes and benefit energetic aqueous batteries. [ABSTRACT FROM AUTHOR]

Zinc‐based aqueous batteries (ZABs) are attracting extensive attention due to the low cost, high capacity, and environmental benignity of the zinc anode. However, their application is still hindered by the undesired zinc dendrites. Despite Zn‐surface modification being promising in relieving dendrites, a thick separator (i.e. glass fiber, 250–700 μm) is still required to resist the dendrite puncture, which limits volumetric energy density of battery. Here, we pivot from the traditional interphase plus extra separator categories, proposing an all‐in‐one ligand buffer layer (ca. 20 μm) to effectively modulate the Zn2+ transfer and deposition behaviors proved by in situ electrochemical digital holography. Experimental characterizations and density functional theory simulations further reveal that the catechol groups in the buffer layer can accelerate the Zn2+ reduction reaction (ZRR) through the electron‐donating p‐π conjugation effect, decreasing the negative charge in the coordination environment. Without extra separators, the elaborated system endows low polarization below 28.2 mV, long lifespan of 4950 h at 5 mA cm−2 in symmetric batteries, and an unprecedented volumetric energy density of 99.2 Wh L−1 based on the whole pouch cells. The concomitantly "separator‐free" and "dendrite‐free" conjugation effect with an accelerated ZRR process could foster the progression of metallic anodes and benefit energetic aqueous batteries. [ABSTRACT FROM AUTHOR]

This study explores the application of abrasive waterjet drilling (AWJD) for varied patterns of GF/Al mesh hybrid composites (neat glass NG, AG: Al in the exterior surface, and GA: Al in the center). Key parameters such as jet pressure (P), standoff distance (S), and traverse speed (V) are systematically varied, influencing material removal rate (MRR), hole taper ratio (Tr), and roundness error (Re). Employing a Taguchi approach with an L9 design. It was indicated that the optimal conditions for maximum MRR are (P: 150 MPa, S: 2 mm, and V: 900 mm/min). V and S are the main influential parameters on Tr and Re. Gray relational analysis (GRA) is employed for simultaneous optimization, enhancing drilling performance. The optimal parameters P of 150 MPa, S of 2 mm, and V of 300 mm/min are determined. Validation trials confirm the effectiveness of the determined parameters. A robust multiple regression equation is formulated, providing a predictive model that aligns closely with experimental observations. Highlights: The hybrid composites were drilled via a nontraditional process.The attributes of the hole geometry and the material removal impacts were studied.Operation parameters were optimized to improve MRR, Re, and Tr.A multiple regression model and a confirmation test were performed and validated. [ABSTRACT FROM AUTHOR]

Elium® Acrylic/Glass Fiber thermoplastic laminate composites are liable to develop irreversible local defects under quasi‐static loading. To reinforce the damaged material, repair is a cost‐effective mechanical alternative. The present study investigates the tensile behavior of an Elium® glass‐fiber‐based acrylic laminate composite panel, repaired by vacuum bonding with Elium® repair resin and double overlap of external patches (DP). The results obtained for all repaired laminate composites E190/GF_D(10, 20, 30)R with diameters 10, 20, and 30 mm showed an improvement in the mechanical properties of the repaired panels, compared with the drilled and pristine samples. Average load recovery rates were significant for E190/GF_D10R (7.9%, 3.55%, 13%) E190/GF_D20R (23%, 18%, 3.32%), E190/GF_D30R (7.2%, 9.36%, 32.37%) at strain rates of 0.001, 0.01, and 0.05 s−1 respectively. Finite element (FE) models for the virgin, drilled, and repaired composite, performed by coupling the Hashin criteria with the cohesive zone model (CZM), provided a relevant prediction of intra‐ and interlaminar failures of these woven laminated composites. Highlights: The effect of vacuum bonding repair with Elium E351 EOT resin was studied.Symmetrical repair of acrylic laminate drilled by fiberglass patches.Tensile strength of the repaired laminates was investigated.Intra‐ and interlaminar damage was predicted by finite elements modeling. [ABSTRACT FROM AUTHOR]

In the pursuit of sustainable and high‐performance materials, this study presents a groundbreaking approach to enhance the mechanical properties of glass fiber‐reinforced polymer composites. Railway waste provides an unexpected source of recycled glass fibers (RGFs), which, when combined with bamboo fibers (BFs) and nano SiO2 in a resilient epoxy matrix, unleashes a transformative synergy. The epoxy‐SiO2 matrix ratio was kept constant, that is,70% by weight while varying the ratio of RGF and BFs weight. The experimental results demonstrated notable improvements in mechanical properties. Specifically, a 36.92% increase in tensile strength was observed with an RGF and BF ratio of 20:10. Flexural strength exhibited a substantial enhancement of 44.67%, and impact strength increased by 31.28% at a ratio of 15:15. The composite achieved a remarkable 42.64% improvement in hardness, while attaining the lowest density value of 0.862 at a ratio of 25:05.Water absorption tests, conducted in both distilled and saline water, provided insights into the material's resistance to environmental conditions. The morphological and dispersion behaviors of the prepared composites were analyzed using advanced characterization techniques, including field‐emission scanning electron microscopy (FE‐SEM) to study the orientation, shape, and size of fibers and particles, bonding between the fibers and matrix, defects, voids, etc. Combined with energy dispersive x‐ray spectroscopy (EDX), FESEM allows for elemental analysis, helping to identify and quantify the chemical composition of different phases within the polymer composite. X‐ray diffraction (XRD) analysis to know the compositions of developed composites. The findings from this study underscore the efficacy of incorporating recycled materials. Highlights: Extraction and reusing GF to develop a new hybrid composite.BF and RGF in epoxy‐SiO2 matrix present high mechanical property composite.Density and water absorption tests were done to see the swelling properties.Characterization technique employed to see the interphase of composites developed. [ABSTRACT FROM AUTHOR]

Glass fiber‐reinforced resin matrix composites have good mechanical and impact resistance properties, while with particle co‐reinforcement, a synergistic effect can further improve their performance. In this paper, continuous glass fiber‐reinforced nylon 6 (GF/PA6) and continuous glass fiber (GF) with glass beads (GBs) co‐reinforced nylon 6 (GB–GF/PA6) were prepared to investigate the co‐reinforcement mechanism and the synergistic effect of particle and fiber. A quantitative parameter of the residual impact force divided by the critical force Pr/Pcr, as the damage degree of the low‐velocity impact, is defined to evaluate the impact resistance of the composite. The results indicate that the damage of GB–GF/PA6 was lower than that of GF/PA6, and the synergistic effect reaches the most obvious at the GB addition of 10 wt%. Scanning electron microscope (SEM) and x‐ray computed tomography (XCT) images disclose that GB impedes the type II crack spread in the matrix and fiber/matrix interface. With the type II cracks reducing, the materials' resistance to delamination can be significantly enhanced. For the composite structure, in which 10 wt% GB and 60 wt% GF are introduced, the flexural strength, shear strength, and pendulum impact strength were tested with the maximum values of 379.4 MPa, 53.1 MPa, and 219.0 J/m2, respectively. This composite structure design, presenting a continuous GF and GBs co‐reinforce effect, offers a manufacturing process that is easily scalable to achieve excellent characteristics. [ABSTRACT FROM AUTHOR]

Composite thin‐walled tubes made of glass fiber reinforced plastics (GFRP) are attracting great attention due to their lightweight and outstanding crashworthiness capacity. Implementing triggers to the design of GFRP composite tubes enables a further increase in specific energy absorption while simultaneously reducing peak crushing force. Motivated by these facts, a notch‐type triggering mechanism is suggested in this work to enhance the energy absorption capabilities of circular GFRP composite tubes. GFRP tube samples with (0°/90°)8 layups are manufactured using the roll wrapping process. Subsequently, these samples are triggered and subjected to quasi‐static axial compression tests. The diameter, quantity and placement of the triggering notches are selected as design parameters, and experiments are carried out using Taguchi's L9 orthogonal array. Each of these parameters has three levels to identify the optimal combination of design parameters. To optimize multiple responses, the weighted aggregated sum product assessment, a multiple criteria decision‐making technique, is employed in conjunction with mono‐criteria optimization. The findings indicated that substantial enhancements can be realized in all parameters related to energy absorption performance by triggering progressive crushing modes in a controlled manner using a notch‐type triggering mechanism. In particular, the findings indicated that the specific energy absorption and the crush force efficiency of the intact GFRP composite tubes could be improved up to 18% and 68.3%, respectively, by the selection of appropriate triggering parameters. Highlights: Axial crushing and optimal design of triggered GFRP tubes are investigatedNumber, diameter, and center distance of the notches are chosen as parametersTaguchi experimental design is used for the best configuration of parametersThe optimum configurations are investigated using the entropy‐WASPASSignificant improvements are achieved using the trigger mechanism [ABSTRACT FROM AUTHOR]

Three‐dimensional woven spacer composites (3DWSCs) with lightweight and excellent mechanical properties have promising application in communication, transportation, aerospace and other fields. However, traditional single‐layer 3DWSCs exhibit insufficient strength, especially when dealing with high thickness, as the pile yarns tend to buckle. In this study, inspired by the structural features of the Thalia dealbata, 3D woven integrated double‐layer glass fiber/epoxy resin spacer composites by mimicking were fabricated. Innovative integrated double‐layer structure design effectively improves the performance and failure mode of 3DWSCs under bending loads. Compared to single‐layer 3DWSCs, the resulting double‐layer 3DWSCs exhibited a 41.79% increase in peak bending load, a 46.85% increase in bending stiffness, and a 99.38% increase in energy absorption. In addition, the double‐layer 3DWSCs showed a low density of 0.52–0.55 g/cm3. This work introduces bioinspired double‐layer 3DWSCs with characteristics of lightweight and superior bending performance, potentially offering novel ideas for the design of high‐performance composites. Highlights: Inspired by the structural features of the Thalia dealbata, a 3D integrated woven double‐layer glass fiber/epoxy resin spacer composites by mimicking were fabricated.3D woven double‐layer spacer composites are lightweight (0.52–0.55 g/cm3) and can effectively improve the bending properties of single‐layer structures.Based on the analysis of the fracture morphology, the significant improvement of the fracture pattern of the single‐layer structure by the double‐layer structure is effectively demonstrated.This study introduces novel design strategies for multi‐layer lightweight composite materials and holds broad applications. [ABSTRACT FROM AUTHOR]

This study investigates the effects of filler content and type on the mechanical (tensile strength and impact resistance) and tribological properties of woven glass fiber‐reinforced composites (WGFC) produced using three different nanofillers (MgO, CuO, and Al2O3) at various loading levels (0.7, 1.4, and 2.8 wt%). Additionally, analyses of the artificial neural network algorithm were reported for the predictions of wear rate, mass loss, and coefficient of friction (COF) by given applied load, sliding distance, filler ratio, and filler type. The composites were fabricated using the hand lay‐up method. The filled composites were characterized using Fourier Transform Infrared (FTIR) spectroscopy, and the worn surfaces of the samples after the wear test were analyzed using Scanning Electron Microscopy (SEM). The wear resistance of the composite samples improved at 0.7 wt% CuO and 1.4 wt% MgO filler contents. At 200 m sliding distance and 1.4 wt% filler ratio, the highest wear ratio was determined as 55 mm3/m × 10−3 in the Al2O3‐filled composite, and the lowest was determined as 31 mm3/m × 10−3 in the MgO‐filled composite. At 1.4% filler ratio and 15 N load, the lowest friction coefficient was determined as 0.45 μ in MgO‐filled composite, and the highest was 0.56 μ in Al2O3‐filled composite. Al2O3 filler increased the mass loss and wear rate of the composite material. In Charpy impact tests, the maximum impact energy of 13.9 J/m2 was obtained with a 2.8 wt% Al2O3 filler content. Tensile tests showed an increase in tensile strength for all filler contents compared to unfilled composites. The highest tensile strength of 242.1 MPa was achieved with 0.7 wt% CuO reinforcement. Highlights: In all applied wear parameters and filler ratios, the Al2O3 filler adversely affected the wear resistance of the composite, while the MgO filler showed the best performance in terms of wear resistance.All types and ratios of fillers increased the tensile strength compared to the unfilled composite.Contrary to its negative effect on wear, the Al2O3‐filled composites exhibited the highest impact resistance.The prediction analysis of the tribological behavior of composite material using ANN reveals that the Levenberg–Marquardt algorithm fits very well. [ABSTRACT FROM AUTHOR]

The preparation of basalt and S‐glass fiber‐reinforced poly(dicyclopentadiene) via ring‐opening metathesis polymerization using a thermally latent pre‐catalyst, that is, Mo(N‐3,5‐Me2‐C6H3)(= CH‐(2‐MeO‐C6H4))(IMes)(OTf)2 (1, IMes = 1,3‐dimesitylimidazol‐2‐ylidene; OTf = SO3CF3) is reported. Complementarily, the non‐latent first‐generation Grubbs initiator RuCl2(PPh3)2(CHPh) (2) is used. 2 can be rendered latent by the addition of ppm amounts of triphenylphosphine (PPh3). Both 1 and 2/PPh3 allow the realization of thermally latent single‐component systems with sufficient pot life that do not require pre‐mixing of the individual components shortly before use. The prepared fiber matrix composites are characterized in terms of mechanical, thermal, and chemical stability. [ABSTRACT FROM AUTHOR]

This study aims to address the complex stress state commonly observed in concrete structures in practical engineering, as well as the challenges posed by resource scarcity and environmental pollution. To achieve this, a total of 168 cylinder specimens of glass fiber recycled coarse aggregate concrete (GFRAC) were designed for conventional triaxial compression tests. The analysis of the test results reveals that the application of lateral restraint force induces a shift in the failure mode of GFRAC from longitudinal splitting failure to plastic deformation failure, occurring either in the middle or at the end of the specimen. The lateral constraint force can effectively improve the stress and strain at the peak point of GFRAC and the modulus of elasticity of the specimen. The glass fiber increases the peak stress of the specimen, and the maximum growth rate is 20%. On the contrary, the glass fiber reduces the peak strain, and the maximum reduction is 49.66%. Increasing the replacement rate of recycled coarse aggregate will lead to a decrease in peak stress, with a maximum decrease of 19.17%. Glass fiber (GF) limits the appearance and propagation of cracks by bridging, pulling out or breaking. Finally, three different failure criteria are used to analyze the triaxial compression state of GFRAC from a macro perspective. [ABSTRACT FROM AUTHOR]

Frontal polymerization (FP) is a self-sustaining reaction that relies on polymerization exothermicity and heat transfer. This study explores the inplane and in-depth FP mechanisms of continuous fiber-reinforced epoxy composites. First, the effects of initiator and diluent concentrations on the FP behaviors of neat epoxy resins were examined. It was found that the frontal velocity and frontal temperature of the neat resins increase with an increase of either the initiator concentration or the diluent content, depending on the polymerization enthalpy and curing kinetics. Then, the FP behaviors of continuous carbon fiber and glass fiber-reinforced epoxy woven composites were investigated. The results showed that the in-plane FP behavior of the composites was primarily controlled by the thermal conductivity and specific heat capacity of the continuous fibers, whereas the in-depth FP behavior mainly depended on the pores of the woven fabrics. Highlights • Frontal velocity and temperature of neat resins are controlled by the polymerization enthalpy and curing kinetics. • The in-plane FP behavior of continuous fiber reinforced composites is dependent on the thermal conductivity and specific heat capacity of the fibers. • The in-depth FP behavior of composite is determined by both the thermal conductivity of fibers and the pores of fabrics. [ABSTRACT FROM AUTHOR]

This work compares the tensile and fatigue behavior of unidirectional glass fiber/epoxy (GFRPs) and basalt fiber/epoxy (BFRPs) composites manufactured using vacuum-assisted resin infusion molding (VARIM). The tensile and fatigue tests are performed, and results show that both GFRPs and BFRPs have very similar tensile behavior, whereas BFRPs perform better than the GFRPs in terms of fatigue life and degradation of properties, showing about 75 MPa more fatigue limit. The S-N curve shows that BFRPs resist fatigue failure and stiffness degradation due to their better interfacial adhesion. Fractographic observations reveal fatigue failure mechanisms of both BFRPs and GFRPs. From the regression analysis performed, an S-N curve was fitted with a model available in the literature, and regression parameters were calculated. Dynamic mechanical analysis of both BFRPs and GFRPs was performed to evaluate parameters like glass transition temperature, storage modulus, and loss modulus. From the findings of this research, BFRPs may be recommended as a suitable alternative to GFRPs. Highlights • This article compares the tension-tension fatigue properties of unidirectional GFRPs and BFRPs. • From the research work, the authors found that BFRPs perform better than GFRPs under fatigue loading. • The stiffness degradation behavior of GFRPs and BFRPs are studied and compared. • Scanning electron micrographs of fractured samples are used to observe fatigue failure mechanisms. • Dynamic mechanical analysis (DMA) was performed to determine the storage modulus, loss modulus, glass transition temperature, and damping coefficient (tand) for both composites. [ABSTRACT FROM AUTHOR]

Composite materials are increasingly used in aircraft structural components with complex structures like L, C, or T shapes, which can cause delamination failure in the thickness direction under complex loading. This research focuses on the experimental investigation of the effect of different adhesive reinforcement phases with an adhesively bonded external patch to examine the residual strength and delamination resistance of repaired glass/epoxy curved samples. The damaged region in curved samples was repaired using adhesive reinforcement phases like neat epoxy, chopped glass fiber, and particulate glass fiber, along with adhesively bonded external patches like hybrid patches of glass/Kevlar (HP G/K), glass/carbon (HP G/C), and intraply patch carbon/Kevlar (IP C/K). The findings show that chopped glass fiber HP G/C patch-repaired curved samples had a curved beam strength (CBS) and interlaminar tensile strength (ILTS) recovery of 222.87% and 149.54%, respectively, as compared to damage area removed samples. In addition, it exhibited higher peak force, residual strength, and less elongation when compared to HP G/K and IP C/K patch-repaired curved samples. According to the findings of this research, composite angle brackets in aircraft structural components can be repaired utilizing an adhesively bonded HP G/C patch filled with chopped glass fiber at the dressed site. Highlights • The effect of patch hybridization on repaired curved laminates was studied. • Four-point bending test was conducted on indented and repaired samples. • Residual strength and delamination behavior were studied. • Chopped glass fiber HP G/C patch repaired samples had higher CBS and ILTS. • Delamination onset and propagation were assessed using Photographic images. [ABSTRACT FROM AUTHOR]

The long-term interfacial shear strength (IFSS) and flexural strength of GFPP bars under the coupling effect of bending and immersion in the simulated seawater and sea sand concrete (SWSC) solution were studied by an acceleration experiment. Three temperatures and three bending stress levels (0%, 9.8%, and 29.4% of the maximum flexural strain of GFPP bars) were used to accelerate the experiment. Results indicate that the degradation of mechanical properties of GFPP bars is relatively sensitive to the immersion temperature. Low bending stress did not accelerate the degradation of GFPP bars compared with unbent GFPP bars while high bending stress dramatically accelerated the degradation. Microscopic tests found there is corrosion of glass fibers and debonding between glass fibers and polypropylene but no obvious chain breaks of polypropylene occurred. Based on the Arrhenius theory, long-term stable retention rates of the IFSS of GFPP bars with zero and low bending stress immersed in the simulated SWSC solution are 42.4% and 52.3%. Highlights • Low-stressed GFPP bars degraded similarly or even slower than unbent GFPP bars. • GFPP bars degraded mainly due to interfacial debonding and fiber corrosion. • Long-term IFSS of GFPP bars under a coupling effect was predicted. [ABSTRACT FROM AUTHOR]

Composite structures with L, C, and T shape geometries are commonly used in the design of aerospace structural components. These complex structures are prone to delamination failure at the curved region. This study investigates the effect of thickness and recycled milled glass fiber fillers to improve the strength properties and delamination resistance of glass/epoxy composite angle brackets. Different thicknesses of 3.5 mm (16 layers), 5 mm (24 layers), and 6.5 mm (32 layers) specimens were subjected to four-point bending test with acoustic emission (AE) monitoring for evaluating damage resistance. Mechanical results reveal that the specimen with a higher thickness of 6.5 mm has better damage tolerance, followed by 3.5 and 5 mm angle brackets. Moreover, the location of AE signals and % of AE hits noticed the initiation and propagation of delamination in 5 mm thickness specimen at the earlier stage of loading. However, the curved beam strength and interlaminar tensile strength (ILTS) of 5 mm thickness specimen were improved by 31.02% and 19.2% respectively, through the incorporation of 2 wt% of fillers. Further, the interfacial adhesion between the fillers and epoxy matrix was studied using Fourier-transform infrared analysis to confirm the improvement of delamination resistance in 5 mm thickness specimen. Finally, the mechanical and AE results were well correlated with field emission scanning electron microscope images to characterize the damage mechanisms in composite angle brackets. Highlights • Effect of thickness on the delamination resistance of composites was studied. • Interlaminar properties of composite angle brackets were assessed. • Acoustic emission parameters were used to study the damage mechanisms. • Recycled milled glass fillers were employed to improve delamination resistance. • Mechanical and acoustic emission results were correlated with field emission scanning electron microscope images. [ABSTRACT FROM AUTHOR]

Development of fifth‐generation technology leads to a growing demand for materials with exceptional thermal property, mechanical strength, and low dielectric loss. However, ensuring the broad application of such materials by comprehensively investigating their aging mechanisms and service lifetimes remains a challenge. In this work, we have developed a glass fiber (GF) reinforced liquid crystal polymer composite (GF/LCP) and conducted a thorough exploration of its aging mechanism, behavior, and service lifetime under thermal and oxidative conditions. On the basis of the general Arrhenius model, the composite maintains a high level of functionality for a remarkable 18 years at 150 °C and 1.5 years at 200 °C. Despite the extremely high thermal resistance of GF/LCP composite, the LCP matrix exhibits localized brittle fracture, and the main chains still undergo gradual degradation to generate phenolic groups, which ultimately leads to severe pulverization and mass loss. However, a high degree of connection maintenance between GF and LCP components is still reserved. This work provides a valuable reference for the reliable application of 5G materials under thermal and oxidative conditions. [ABSTRACT FROM AUTHOR]

ZnO thin films were prepared by sol‐gel spin coating on a glass substrate via green synthesis using Uncaria gambir leaf extract. The deposited films were characterized for structural, morphological, and optical properties at various annealing temperatures (400, 500, and 600 °C). The ZnO film without annealing shows an amorphous structure, and after annealing, it shows a hexagonal wurtzite structure with a dominant (101) peak. The crystallinity of the films increases up to 500 °C. The crystallite size shows a maximum value (27 nm) at 500 °C. Also, a flat, smooth, uniform wrinkle and the homogenous surface of ZnO thin films are shown at 500 °C. The gambir extract prevents the segregation of crystallites until 500 °C. The transparency was over 80 % in the visual region for all annealed films, and the energy bandgap decreased to 3.81 eV with increasing the annealing temperature up to 500 °C. [ABSTRACT FROM AUTHOR]

Air filtration is vital for passive pollution control toward advanced manufacturing industries and human health protection. However, large‐scale air‐filter utilization is limited by high energy costs. Therefore, it is crucial to develop filter media that exhibit a high removal efficiency, low pressure drop, and stable biocidal effects. This study reports an efficient and scalable bottom‐up approach for fabricating shellac‐based glass fiber matrices with bioprotective traps (GFMs‐traps) with tunable conformal micro/nanostructures, superhydrophobicity, and biocidal functions. The synthesis, which involves freeze‐drying‐free ice‐shellac double‐template formation, perfluorosilane‐based grafting, and filtration, eliminates capillary‐force‐induced micro/nanofibrous cluster formation. Theoretical modeling and experimental results indicate that the air cleaning and biocidal properties of the GFMs‐traps can be attributed to their uniformly distributed micro/nanofibrous structures and stable nanoparticle (NP) coatings (AgNPs, CuNPs, and TiO2NPs). The GFMs‐traps exhibit integrated air cleaning, with excellent filtration performance at the most penetrating particle size (99.97%, 234 Pa), superhydrophobicity (≥150°), a high virus‐filtration efficiency (99.995%), and good antibacterial and antiviral activity. Additionally, a commercial air purifier comprising a GFMs‐trap filter exhibits high potential for commercial applications. The facile strategy for fabricating high‐performance bioprotective filter media reported here may facilitate advanced large‐scale air filtration applications in the future. [ABSTRACT FROM AUTHOR]

The natural and synthetic fibers are combined in a single composite to achieve a balance between the desired strength and cost considerations. In this study, the vacuum resin transfer moulding process was used to prepare an epoxy‐based composite. The composite consisted of grewia optiva as the natural fiber and glass fiber as the synthetic fiber, both with a fixed weightage of 10 %. Dolomite was used as a filler with varying content (0 %, 5 %, 10 %, and 15 weight %). The physical, mechanical, erosion wear and morphological behavior of the epoxy‐based composite were investigated. The inclusion of dolomite filler significantly increased the composite hardness and impact strength but reduced its tensile and flexural strength. At a dolomite filler content of 10 weight %, the erosive wear was reduced, while it increased at higher dolomite filler contents. The composite was examined using the L16 array, and the minimum wear rate was observed at an impingement angle of 30°, a velocity of 10 m/s, and an erodent size of 150 μm. Morphological studies were conducted to explore the possible mechanism for the variation in erosive wear at different dolomite contents in the hybrid composites. [ABSTRACT FROM AUTHOR]

The development of fifth‐generation technology has resulted in increased demand for materials with low dielectric losses and superior thermal and mechanical properties. However, ensuring the widespread use of such materials by investigating their aging mechanisms and operating lifetimes remains challenging. In this study, a glass‐fiber (GF)‐reinforced acrylate‐styrene‐acrylonitrile/polycarbonate (ASA/GF/PC) composite is designed and comprehensively investigated its aging behavior, mechanism, and service lifetime under long‐term hygrothermal conditions. Based on the general Peck model, the composite maintains a high level of quality for over 10 years, including under harsh conditions of 40 °C and 80% relative humidity. The aging mechanism is primarily ascribed to cracking between the GF fibers and matrix, the breaking of chemical bonds, the generation of new cross‐linked domains, and physical aging. These findings provide valuable insights into the long‐term utilization of ASA/GF/PC composites in harsh environments. [ABSTRACT FROM AUTHOR]

Zn metal batteries have garnered considerable scientific and technological interests. However, the widespread commercial application of these batteries is impeded by the uncontrollable dendrite growth and consequent severe side effects. Herein, a functionalized separator is prepared by spraying polyaniline‐modified graphene oxide (denoted as NPGO)/polyvinylidene difluoride solution directly on one side of a common separator of glass fibers (GFs). The reversible transition between protonated and deprotonated states of quinolone imide on NPGO nanosheets can facilitate the rapid desolvation and transfer of Zn2+. Therefore, the spatial electric field as well as the Zn2+ flux is effectively homogenized due to the ion‐sieving effect of NPGO nanosheets that are oriented toward Zn anode. This engineering design of the NPGO@GFs separator harvests excellent rate and cycling performance (over 3000 cycles at 20 mA cm−2) for Zn metal symmetric batteries. Meanwhile, it provides an impressive commercial prospect (500 cycles with a capacity retention of 91.6% under 2000 mA g−1) for MnO2||Zn full batteries. Such a strategy can be generalized as a common way to protect metal anodes (Na, Zn, and K) in rechargeable batteries, which is highly cost‐effective and scalable. [ABSTRACT FROM AUTHOR]

Here, we report on core–clad bioactive borosilicate fibers, that we have prepared both with round and rectangular cross‐section profile. The exposed approach, which relies on the stacking and drawing of glass slabs, demonstrates our ability to develop bioactive‐based glass fibers with tailored cross‐section profiles. Tens‐of‐meters‐long fibers were successfully drawn, although suffering from elevated losses in the case of the rectangular ones. The response of the fibers in simulated body fluid was studied for both geometries. We found that a round cladding can act as protective layer, tempering effects of the corrosion. We also noticed that rectangular fibers are more prone to degradation, the enhanced corrosion beginning from their sharp corners as they accumulated residual tensile stress during drawing. To the best of our knowledge, this is the first report on the effect of residual tensile stresses from surface tension deformations applied to the corrosion of rectangular fibers. As geometry plays a critical role on the biodegradation behavior of the fiberglass, we believe the enclosed results could lead to the design of fiber devices with tailored cross‐section profile in order to tune their rate of degradation on solely based geometrical effects. [ABSTRACT FROM AUTHOR]

Gallium‐rich heavy metal oxide glasses have become highly attractive optical materials since they exhibit a wide transparency window spanning from the ultraviolet ∼270 nm up to the mid‐infrared (IR) region ∼6 μm making them promising for a future integration in optical fiber devices. Nonetheless, in most composition, surface crystallization is a key limiting factor for optical fiber drawing using the classical preform‐to‐fiber method. Herein, taking advantage of structural information from vibrational spectroscopies (Raman/IR) and 71Ga Solid‐State Nuclear Magnetic Resonance, we describe the key role of lanthanum and yttrium rare—earth elements on the glass structure and their impact on the capability to draw those new glass compositions into optical fibers. This approach emphasizes that yttrium ions as compared with lanthanum ones favor the glass disorder, increasing significantly the fraction of GaO5 units with respect to GaO4. That, combined with thermal analysis and examination of the crystallization behaviors, highlights that Y2O3 prevents the glass devitrification during the glass shaping. The smaller yttrium radius is believed to be the key physical parameter preventing the precipitation of the BayGa5‐yGey+1La3‐yO14 (y = 0, 1, 2, 3) langasite‐type crystal phase. This study remains particularly relevant and opens up the way for the development of highly robust power scaled fiber devices operating from the visible up to the challenging mid‐IR domain. [ABSTRACT FROM AUTHOR]

Polyamide polymers are widely used in tribological areas in a wide range of industries. The purpose of this study is to extend the tribological life of this material. For this purpose, composite materials were produced by adding solid lubricants such as graphite and wax to the polyamide 6 (PA6) matrix at different rates, and the synergistic effect of these composites on tribological behavior was investigated. Tribological experiments were carried out under dry sliding conditions and on themselves. The polyamide 6/graphite/wax composites were first produced in the form of granules in a twin‐screw extruder, and then test samples were molded using the injection molding technique. Wear tests were performed using a pin‐on‐disc wear device. Tribological tests were carried out at a sliding speed of 0.5 m s−1 and under loads ranging from 10 N to 250 N. Following the experiments, the friction coefficient, specific wear rate, and surface wear were determined under the condition of the materials working on each other. The results showed that the lowest specific wear rate and friction coefficient were obtained for the polyamide 6 composites containing 6 % wax and 15 % glass fiber working on each other. [ABSTRACT FROM AUTHOR]

The durability of short fiber reinforced polymers (SFRPs) is affected by several variables. Accurate unifying fatigue parameters are thus essential for an efficient characterization campaign. This research investigated the fatigue behavior of a Polyphtalamide PA6T/6I reinforced with 50% of glass fibers. Two thicknesses (1.6 and 3 mm), two orientations from the injection molding direction (0° and 90°), and three load rations (−0.5, 0.1, 0.5) were investigated. A new fatigue parameter, called alternating energy density (AED), was presented; its ability to correlate the fatigue tests results was compared to other known fatigue parameters—cyclic mean strain rate and cyclic creep energy density. All the fatigue parameters were found to be independent of specimen thickness. Furthermore, the prediction of the fatigue lifetime based on AED showed greater accuracy with respect to the other known investigated methods. AED could thus be used for accurate and efficient lifetime prediction of SFRPs. Highlights: A new unifying fatigue parameter for SFRPs called AED is proposed.AED proved higher unifying capabilities than other known methods.A new SFRP fatigue database including thickness, orientation, and load ratio is provided. [ABSTRACT FROM AUTHOR]

Lightweighting of automotives is crucial for the decrease of fuel and energy consumption, as well as CO2 emission and environmental pollution. Polymer composites, especially the high strength glass fiber/polyamide (GF/PA) composites, have great potential in lightweight; however, they have not been universally accepted due to their insufficient performance. Here, a stearate‐ended hyperbranched polyester (HBP‐12‐n) is designed and high‐performance GF/PA6 composites with high GF content are prepared. The flowability of the composites can be further increased by combining carboxyl‐ended hyperbranched polymer (HyPer C181) with HBP‐12‐n. Compared with unmodified GF/PA6 composites, the melt flow index (MFI) can be increased remarkably to 587% by adding a 0.7 wt% mixture of HBP‐12‐75 and HyPer C181, and the strength and toughness remain competitive. The simultaneous improvement in MFI and impact strength of GF/PA6 composites is the first discovery of this kind, and a synergistic mechanism of amphiphilic bridging‐deformation slipping‐interfacial strengthening of hyperbranched polymers is proposed to account for this phenomenon. This work provides a simple strategy to fabricate GF/PA6 composites with the extensive application for automotive parts and has great prospects in making automotives lightweight and reduction of CO2 emissions. [ABSTRACT FROM AUTHOR]

Room temperature sodium sulfur (RT Na‐S) batteries with high theoretical energy density and low cost have recently gained extensive attention for potential large‐scale energy storage applications. However, the shuttle effect of sodium polysulfides is still the main challenge that leads to poor cycling stability, which hinders the practical application of RT Na‐S batteries. Herein, a multifunctional hybrid MXene interlayer is designed to stabilize the cycling performance of RT Na‐S batteries. The hybrid MXene interlayer comprises a large‐sized Ti3C2Tx nanosheets inner layer followed by a small‐sized Mo2Ti2C3Tx nanoflake outer layer on the surface of the glass fiber (GF) separator. The large‐sized Ti3C2Tx nanosheet inner layer provides an effective physical block and chemical confinement for the soluble polysulfides. The small‐sized Mo2Ti2C3Tx outer layer offers an excellent polysulfide trapping capability and accelerates the reaction kinetics of polysulfide conversion, due to its superior electronic conductivity, large specific surface area, and Mo‐rich catalytic surfaces. As a result, RT Na‐S batteries with this hybrid MXene interlayer modified glass fiber separator deliver a stable cycling performance over 200 cycles at 1 C with an enhanced capacity retention of 71%. This unique structure design provides a novel strategy to develop 2D material‐based functional interlayer for high‐performance metal‐sulfur batteries. [ABSTRACT FROM AUTHOR]

Bismuth (Bi)‐doped glasses with broadband near‐infrared (NIR) emission have been drawing increasing interest due to their potential applications in tunable fiber lasers and broadband optical amplifiers. Yet, the implementation of highly efficient and ultra‐broadband Bi NIR emission covering the whole telecommunication window remains a daunting challenge. Here, via a metal reduction strategy to simultaneously create a chemically reductive environment during glass melting and enhance the local network rigidity, a super broadband (FWHM ≈ 600 nm) NIR emission covering the entire telecommunications window with greatly enhanced intensity was achieved in Bi‐doped germanate glasses. More importantly, due to the excellent thermal stability, the super broadband Bi NIR emission can be well retained after the glass was drawn into an optical fiber. Furthermore, the transmission loss of 0.066 dB/cm at 1310 nm and an obvious broadband amplified spontaneous emission spectrum spanning a range of 1000–1600 nm were observed in this fiber. This work can strengthen our comprehension of the complicated Bi NIR luminescence behaviors and offer a feasible and universal way to fabricate tunable fiber lasers and broadband optical amplifiers based on Bi‐doped multicomponent glasses. [ABSTRACT FROM AUTHOR]

Conventional constant amplitude life diagrams (CLDs) model cannot reasonably describe mean stress effect and stochastic uncertainty present in the fatigue failure process of composite materials. To address this problem, taking the spatial mapping relationship between probabilistic S‐N curves and probabilistic CLD model as an entry point, a probabilistic CLD modeling method is proposed under the assumption of linear equations and the assumption of equiprobable quantile point between static strength distributions and fatigue life distributions. The p‐S‐N curve is established using fatigue test data from different load zones divided by different stress ratios. Subsequently, the p‐CLD model is derived through the spatial mapping relationship of the p‐S‐N curve. The method is validated by fatigue test data of glass fiber/polyester resin composites. The results indicate that the proposed method can offer an accurate description of the probabilistic behavior of composite materials. [ABSTRACT FROM AUTHOR]

Fiberglass porous ceramics were successfully prepared via a foam‐gelcasting process with fiberglass and glass particles. The effects of fiber content on the rheology of foaming slurries and the structure and mechanical properties of as‐prepared porous ceramics were investigated. The results showed that as the ratio of fiberglass to glass particles increased, the thixotropy of slurries decreased, which affected the foamability of slurries. When the ratio of fiberglass to particle was 75:25, the slurries exhibited excellent flowability and outstanding foamability, which was beneficial to optimize the structure of pores and improve the properties of the porous ceramics. The porosity, compressive strength, and thermal conductivity of porous ceramics with a content of 75 wt.% fiberglass treated at 750°C were 78.3%, 2.15 MPa, and.11 W/(m·K) (room temperature), respectively. Therefore, the prepared porous ceramics with a ratio of fiberglass to particle 75:25 were regarded as an ideal candidate for thermal insulation materials. [ABSTRACT FROM AUTHOR]

Recently developed methods for high resolution birefringence measurement have been applied to distinguish between the surface and interior birefringence of silica glass fibers as a function of drawing temperature and initial surface condition for two types of silica glass with different water contents. Fibers were drawn in a water‐free argon environment using graphite heating elements. It was found that fibers drawn at lower temperatures resulted in greater, interior birefringence, in agreement with previous reports. Additionally, it was found that in the case of low‐water silica glass, flame polishing via oxygen–hydrogen mixture and drawn into fibers at lower temperature resulted in significant surface compressive stress upon drawing. This compressive stress may be the result of surface stress relaxation in silica glass that occurs in the presence of water during fiber drawing. In silica glass that contains greater internal hydroxyl impurity concentrations, the interior birefringence as well as the surface stress relaxation was significantly reduced under the same fiber drawing conditions. Characterization of such stress responses provides insight into the effects of common processing techniques as well as impresses the significance of preform processing for consistent fiber production. [ABSTRACT FROM AUTHOR]

Practical implementation of alkali metal batteries currently still faces formidable challenges because of the dendrite growth upon continuous charge/discharge processes and the associated unstable solid–electrolyte interphase. Herein, it is reported that dendrites can be fundamentally mitigated in lithium and sodium metal batteries by regulating the Li+ and Na+ flux using a glass fiber (GF) separator impregnated with polytetrafluoroethylene nanospheres (PTFE‐NSs), which results in homogeneous deposition of Li and Na during charging. The COMSOL Multiphysics simulations reveal that the introduction of negatively charged PTFE‐NSs into the GF separator enhances the local electric field near the anode, thereby boosting the transfer of cations. It is demonstrated that Li//Li and Na//Na symmetric cells utilising a PTFE‐GF separator show outstanding cycle stability of 1245 and 2750 h, respectively, at 0.5 mA cm−2. Moreover, the Li//LiFePO4 and Na//Na3V2(PO4)2F3 full cells exhibit remarkably improved capacity retention when cycled at 1 C, in the presence of a PTFE‐GF separator. The nuclear magnetic resonance spectroscopy studies suggest that the impregnation of PTFE‐NSs into GF helps "liberate" more Li+ and Na+ and changes the coordination interaction between ions and solvents, contributing to the enhanced electrochemical performance. [ABSTRACT FROM AUTHOR]

As ionizing radiation can cause harmful effects to human and electronic devices, accurate dose monitoring plays an important role in fields such as radiotherapy, nuclear industry, and aerospace. Currently, it is still a challenge to fabricate a miniaturized dosimeter that can achieve real‐time monitoring. Here, a gallosilicate glass with potential application in visualization detection of ultraviolet and ionizing radiation, as well as cumulative dose measurement, is presented. Color centers are induced in the glass upon exposure to ultraviolet or ionizing radiation, resulting in a darkening effect. The color change of glass is related to the energy and intensity of incident photons and can be erased by subsequent heat treatment. Electron paramagnetic resonance measurement indicates that the formation of color centers is associated with non‐bridging oxygen hole centers related to gallium. The glass can be fabricated into fiber with perfect core‐cladding structure, which provides an alternative for preparing a new type of high‐sensitivity radiation dosimeter. [ABSTRACT FROM AUTHOR]

Modern‐day research in composite material development primarily focuses on tailoring combinations by proportions of constituent materials and monitoring the changes in their targeted properties. In line with this trend, a new class of glass fiber reinforced polymer hybrid composite beam of size 600 mm×50 mm×6 mm is fabricated by adding graphene (average particle size:10 μm), and flyash (average particle size: 60 μm). The dynamic behavior of the hybrid beam by introducing two transverse cracks at different positions with varying crack depths is studied by employing analytical, finite‐element, and experimental approaches. The dimensionless relative natural frequencies of the cracked/faulty hybrid beam obtained by the proposed methods are compared with the intact hybrid beam. Also, a comparison is made for the hybrid beam with a single crack. An increase in relative crack depth resulted in an increase in values of dimensionless compliances. Further, the effect of fiber orientation and lamina stacking sequence on the dynamic parameters of the hybrid beam are also analyzed. The introduction of the second crack induces higher nonlinearity in bending modes of vibration. [ABSTRACT FROM AUTHOR]

In this study, we have designed a paper based loop‐mediated isothermal amplification‐lateral flow (LAMP‐LF) Assay that integrated the use of self‐designed lyophilized paper LAMP buttons as ready‐made LAMP master‐mix for on‐site detection of tissue of buffalo origin. Based on mitochondrial cytochrome b gene sequences, a pair of LAMP primers and probes were selected and designed, respectively. Herein, we optimized LAMP reaction components and thermal protocol to evaluate LAMP amplification in various paper matrices frequently used in diagnostics (cellulose, glass fiber, and nitrocellulose). The hybridization conditions of probes, as well as other components of paper LAMP‐LF Assay, were further optimized. Our low‐cost paper based system demonstrated high specificity and was able to detect as low as 10 fg of target DNA. The efficiency and accuracy of the assay were determined targeting coded meat/tissue samples, binary meat admixture, processed meat samples, Phire Animal Tissue Direct PCR kit, and by investigating the consistency between paper based LAMP‐LFA and conventional PCR outcomes. Furthermore, the paper platform was allowed for refrigeration‐temperature storage to determine its ability for deployment in low settings areas. In the current investigation, the time required from sample collection to detection was approximately 2–3 hr. [ABSTRACT FROM AUTHOR]

For commercial civil applications of laminated composite material, characterizations to forecast the interlaminar shear behavior and viscoelastic response across a wide temperature range are essential. In this study, the interlaminar shear strength (ILSS) of glass/epoxy (GE) composites dispersed with binary nanofillers nanosilica‐multilayer graphene (NS‐MLG) and nanosilica‐nanoclay (NS‐NC) was analyzed at an in‐situ testing temperature of 20, 70, and 110°C. Further, the viscoelastic property of the composites was studied using a dynamic mechanical thermal analyzer (DMTA) in the temperature range of 35–165°C. An increase in the ILSS value of around 9% and 10% was observed at room temperature for GE/MLG‐NS and GE/NC‐NS, respectively, compared to control GE composites. In contrast, the trend was seen to change at higher temperatures. There was a slight decrement in the storage modulus (E′) of GE/MLG‐NS and GE/NC‐NS composites in the glassy region compared to control GE composites. The mean Tg of the GE composite (control) was nearly 107.3°C when the E′ decline onset temperature was taken into account, but after the addition of MLG‐NS, it was 10.1°C below. The mean Tg of GE/NC‐NS was determined to be 106.3°C, and in the glass transition as well as rubbery regions, it was observed to compete with the E′ value of the control GE composites. Fractography was done using micrographs obtained from environmental scanning electron microscope (ESEM). Traces of polymeric material found at the fiber surface certified the improved interfacial adhesion between glass fiber and polymer in the matrix‐modified composite samples. [ABSTRACT FROM AUTHOR]

Even though laminated FRP composites show exceptional performance in various modes of loading, they are susceptible to delamination. The ambient temperature and elevated temperature delamination resistance of glass/carbon fiber interply hybrid composites were assessed via mode I and mode II interlaminar fracture toughness tests performed at 30, 50 and 70°C. Interply hybrid composites performed better than composites with single type of fiber. The fracture toughness of inter‐ply hybrid composites varied with the stacking position. At 30°C, mode I fracture toughness value of alternative glass and carbon fiber stacking sequence (G1C1)5 of hybrid composite showed 40% improvement over 10 layered carbon/epoxy (C10) composite. Further, Mode II fracture toughness of C5G5 composite showed 22% enhancement, and C10 exhibited 42% improvement over 10‐layered glass/epoxy composite. Increasing the test temperature of all composites improved their GIC and GIIC values. The increment in the mode I fracture toughness properties of all composite was in the range of 5%–23% at 70°C from its room temperature value. The fractographic images of fractured samples were studied under a scanning electron microscope and failure mechanisms of composites were identified. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (ZIBs) enjoy a good reputation for being safe, affordable to produce, and ecologically friendly due to the use of water‐based electrolytes. The main factors restricting the development of ZIBs, however, are the negative effects of dendrite deposition on the zinc anode and the dissolution of common cathodes such as Mn and V‐based cathodes. Various techniques have been used to address these issues, including regulating the electrolyte concentration or solvation structure, developing a coating or current collector to lessen anode dendrite growth, and improving the structural stability of the cathode. Recently, functionalized separator strategies have gained popularity as effective ways to improve ZIB performance. The use of a functionalized separator is also a practical technique to save costs and increase the volumetric energy density of the battery by substituting a functionalized separator for the usual thick and expensive glass fiber separator. The development of functionalized separators in ZIBs is the subject of ongoing research, and this work presents the most recent findings in a systematic manner, focusing on both the effects and the methods to prepare or modify them. Finally, a brief explanation of the constraints and future potential of current functionalized separator development is provided. [ABSTRACT FROM AUTHOR]

The ease of estimating the uncertainties of numerical simulations in metal forming is of particular interest. This uncertainty arises from, for example, material parameter identification, geometric dimensions, external loads, and contact conditions. In this paper, we aim to address this issue with the extension to geometric influences, and boundary as well as friction conditions. The uncertainty quantification from material parameter identification – here, in terms of sensitivities of the resulting simulations based on the confidence interval of the parameters – is transferred from the literature and the individual proportions are quantified and compared, respectively. For material parameter identification, experiments on steel and glass fiber reinforced plastic are used and the confidence intervals are determined. Particularly in the case of sequential determination of the parameters, the uncertainties are estimated with the aid of Gaussian error propagation. This concept can also be transferred to geometric dimensions or loads. The application of numerical differentiation for the sensitivities within the Gaussian error propagation leads to a concept where the finite element program can be treated as a black‐box. Here, all uncertainties of the simulation results are obtained, leading to the result that geometric influences in the deep drawing process used as well as the friction coefficient have the largest effect. This provides a very simple procedure for the uncertainty quantification of all individual influencing variables in any finite element simulation. [ABSTRACT FROM AUTHOR]

In this study, a statistical approach was developed to predict fatigue failure of laminated composite leaf springs prepared with carbon nanotube (CNT) filled epoxy/woven glass fibers. Electrical resistance change method and the Weibull analysis were adopted to develop a statistical approach. The electrical conductivity for successful application of health monitoring of leaf springs was achieved by dispersing 0.4 wt% of CNTs into epoxy resin. In‐situ monitoring of damage in composite leaf springs during fatigue tests applied as cyclic flexural deflection was carried out at nine different displacement ratios. The critical fatigue cycle and the corresponding change in electrical resistance were determined at each displacement ratio. Then, the critical electrical resistance change to cyclic fatigue was found 0.15% with 95% reliability by the Weibull analysis. The average fatigue life and the average strength loss corresponding to the 0.15% resistance change ratio were found to be 48.33% and 9.88%, respectively. The reported statistical concept based on the monitoring of change in electrical resistance during deflection can be successfully employed as a useful tool to predict safety limits of composite structures subjected to fatigue loading, especially in aerospace industry. [ABSTRACT FROM AUTHOR]

The present study concentrates on the mechanical, morphological, water absorption and burning behavior of hemp/E‐glass fiber reinforced hybrid composites (FRHC). The surface adhesive characteristics of the acquired bi‐directional hemp fiber mats were enhanced by treating them with an alkali solution. Furthermore, the present work extends to identify the effects of two 2‐dimensional graphene and MXene nanoparticles as filler on the hardness, flexural and tensile behavior as well as water absorption and flammability characteristics of the FRHC. The glass fiber (G), hemp fiber (H), and hemp/glass (G/H) fiber reinforced epoxy LY556 laminates were fabricated by using the hand lay‐up method followed by the vacuum bagging approach. A 30% and 12% increase in the flexural and tensile strength of the H/G hybrid composite has been observed by adding 1% of graphene as an additional reinforcement compared with the neat FRHC. However, the use of MXene as additional reinforcements shows 45% and 10% enhancement in the flexural and tensile strength of the H/G hybrid composite. In addition, the water absorption capacity of MXene‐filled G/H hybrid composites is found to be almost half of that filled with graphene. Similarly, the flammability results reveal that the burning rate of graphene‐reinforced H/G hybrid composite is 17.44 mm/min. When comparing the mechanical, water absorption, and flammability characteristics of graphene and MXene‐reinforced G/H hybrid composites, graphene gives more intensifying results than MXene. The scanning electron microscopic studies are also incorporated to investigate the fractured surface topography of the FRHC. [ABSTRACT FROM AUTHOR]

Overview of the materials used in the CUBE The article provides a general description of the building materials used for the two building parts BOX and TWIST of the carbon reinforced concrete building CUBE. The focus of the article is on the presentation and explanation of the decisive material properties of those building materials that are not yet subject to a product standard and whose use was therefore subject to approval in individual cases (in German: Zustimmung im Einzelfall, ZiE). These included seven different concretes, three carbon fabrics, two different carbon rods, glass fibre rods and three high‐performance insulating materials. [ABSTRACT FROM AUTHOR]

In this study, the mechanical properties and damage modes of pultruded glass fiber/unsaturated polyester composite square pipe for automotive parts were investigated. The pipe structure, fiber mass content, dynamic mechanical analysis, tensile, and bending properties and acoustic emission detection damage mechanism of pultruded glass fiber composite pipe were studied. The structure of the cross‐section of the pultrusion pipe is like a sandwich composed of mat layers on both surfaces and a unidirectional fiber layer in middle. Based on the failure analysis of pipe by acoustic emission signal technology, it is found that the tensile damage process was considered into four stages, initial damage, mat layer fracture, intermediate damage, and fiber fracture; while the bending damage process can be divided into two stages as initial and overall damages. [ABSTRACT FROM AUTHOR]

A complete study on the relation between the injection molding parameters and the resulting fiber length, orientation and mechanical properties is presented for highly reinforced long fiber thermoplastic (LFT) polypropylene (PP). It has been found that the longest fibers obtained are the ones processed with the lowest backpressure and the highest screw speed. The backpressure gains importance over screw speed when the amount of glass fiber reinforcement increases, contrary to what was found for less reinforced thermoplastics. The injection speed does not influence the fiber breakage phenomena, while it has great importance in fiber orientation and thus on the tensile strength, especially when the weight fiber average length is below 1000 μm. When this average is over 1000 μm, fibers begin to weave a mesh that thickens the core region and hinds its orientation, reducing the tensile strength but improving impact resistance. [ABSTRACT FROM AUTHOR]

Glass fiber reinforced plastic (GFRP) has become one of the most commonly used materials in the structure of aero engines in the last decades. In this study, GFRP was fabricated by molding with phenolic resin as the matrix. Specimens were prepared along horizontal and vertical directions. Fiber distribution, tensile properties, long‐term creep performance, and damage mechanism were systematically investigated. Experimental results shows that horizontal specimens have better tensile properties, lower viscoelasticity, and excellent creep resistance. The fibers inside the cylindrical material exhibit a 3D core‐shell morphology with transverse isotropy in the core region. Load is carried by the fibers and the damage is in the form of fiber fracture and pull‐out in horizontal specimens. Random distribution and interweaving leads to double fracture sections of fibers. Load is carried by the interface and resin, and the damage is in the form of fiber pull‐out laterally and interfacial debonding in vertical specimens. High viscoelasticity of the resin and the weak interfacial bonding ability lead to large creep deformation of vertical specimens. In addition, the creep strain under different loads can be accurately predicted by Modified Time Hardening model. [ABSTRACT FROM AUTHOR]

Room‐temperature sodium–sulfur (RT/Na–S) batteries are a promising low‐cost energy storage technology. However, the vital role of the separator in the system is often overlooked. Inspired by the maintenance of brain homeostasis by human brain capillaries, this work pioneers a host–guest self‐assembled strategy for covalent organic scaffold membranes, endowing the membrane with multiple functions (sodium ion transport, confinement, and conversion of polysulfides) to maintain the stability of the RT/Na–S battery system. The free‐standing multifunctional covalent organic framework membrane (HB/CNT@COF) maximizes the roles of the host framework and guest molecules. Because of the synergistic effect of hydroxynaphthol blue (HB) and multiwalled carbon nanotubes (CNT), the HB/CNT@COF cell exhibits a capacity of 733.4 mAh g−1 with limited capacity fading after 400 cycles at 4 C. This performance is nearly four times that of commercial glass fiber separators. Additionally, the cell demonstrates excellent performance under electrolyte‐poor conditions. [ABSTRACT FROM AUTHOR]

For the evaluation of the double cantilever beam (DCB) test several approaches are applicable that can provide different results. This ambiguity can significantly affect numerical models which refer to experimentally obtained material parameters. In this work, different approaches for the test evaluation are presented. It is shown that equations derived from the beam theory give reasonable results and good agreement between experiments, numerical and analytical solutions. In this context, DCB tests of glass fibre reinforced polymer substrates with carbon nanotube enriched composites are conducted. A slight negative effect of the latter on the experimental results is found. [ABSTRACT FROM AUTHOR]

Aiming at the use of glass fiber reinforced poly‐ether‐ether‐ketone (GF/PEEK) with low laser absorbance in laser assisted tape winding/placement (LATW/LATP), a method for dyeing GF/PEEK prepreg with nanoparticle fillers (NFs) is presented. First, the effects of carbon black (CB) and graphite (G) NFs on composites laser absorbance and reflection pattern were quantified, and the complex refractive index model was derived. Next, the effects of NFs on composites transverse thermal conductivity were tested, and the accuracy of four thermal conductivity prediction models were compared. Finally, the effects of NFs on composites interlayer performance were studied. The optical test results showed that NFs could improve laser absorbance while not changing reflection pattern, and the increase rate of absorbance for CB was higher than for G. As calculated by complex refractive index model, GF/PEEK with 1‐layer thickness could achieve complete laser absorption by addition of either 2.74%CB or 3.78%G. The thermal conductivity test results showed that NFs could improve composites transverse thermal conductivity. The increase rate of thermal conductivity for G was higher than for CB. Among the four prediction model, the Lewis‐Nielsen model had correct prediction regularity and was within 10% predict deviation. Based on this model, the transverse thermal conductivity of GF/PEEK/2.74%CB was 0.557 W/m K, and of GF/PEEK/3.78%G was 0.592 W/m K. The mechanical test results showed that the CB loading ≤4% had little effect on interlayer performance, while the G decreased interlayer performance. Consequently, adding CB at a low loading is a better way to realize GF/PEEK application in LATW/LATP. [ABSTRACT FROM AUTHOR]