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This study fabricates multiscale glass fiber/epoxy composites by incorporating graphene nanoparticles (GNPs) and zinc oxide nanoparticles (ZnO NPs) to investigate the influences of NPs on the mechanical properties of composites. The composites are manufactured using the compression molding technique with different GNP contents (i.e., 0, 0.5, 1, and 1.5 wt.%), whereas the contents of glass fibers and ZnO NPs remained the same at 40 and 4 wt.%, respectively. Their mechanical properties, chemical compositions, and fracture morphologies are then evaluated. It is found that the mechanical properties of composites improve significantly at a lower content (i.e., 0.5 wt.%) of GNPs and tend to decrease at higher contents (i.e., 1 and 1.5 wt.%). The composite is composed of 0.5 wt.% GNPs exhibit maximum tensile modulus and strength of 6.74 GPa and 230.25 MPa, and flexural modulus and strength of 16.43 GPa and 831.79 MPa, respectively, impact strength of 47.25 kJ m−2, and maximum hardness (97.96 Shore D), among all nanocomposites. Moreover, fracture morphologies reveal that composite failure is predominately caused by fiber breakage, fiber‐matrix debonding, voids, and GNP agglomeration. The outcomes of this study provide some insights to promote the application of manufactured multiscale composites in the aerospace, automotive, and marine industries. [ABSTRACT FROM AUTHOR]

AbstractThis article proposes a glass fiber reinforced plastic (GFRP) wave spring and conducts a study on its free and constrained vibration characteristics and compression performance. Initially, a stiffness prediction model for composite wave spring is established using laminated plate theory and Moore’s theorem. Additionally, the failure mode of the composite wave spring was predicted and experimentally confirmed using ABAQUS and the 3D-Hashin failure criterion. Finally, the vibration characteristics of composite wave spring and metal helical spring are investigated using the B&K testing system in both free and constrained states. The experimental stiffness and ultimate load of the composite wave spring are 20.67 N/mm and 1386.67 N. The composite wave spring exhibits good vibration reduction performance in both free and constrained states, with maximum vibration attenuation amplitudes of 122.71 and 144.93 dB. In comparison, the metal helical spring has maximum vibration attenuation amplitudes of 41.65 and 111.89 dB. [ABSTRACT FROM AUTHOR]

Electromagnetic interference (EMI) shielding composites with both thermal response/management functions and message transfer/encryption behavior are ideal for use in fields such as aerospace, construction engineering, and military equipment. In this work, a self‐cross‐linking supramolecular solid–solid phase change polyethylene glycol (ScPEG) coating is prepared based on multiple hydrogen bonds, which is used for encapsulating glass fiber fabric (GFF) modified with silver nanowires (AgNWs). The solid–solid phase change coating is obtained through the hydrolysis‐condensation of PEG with a reactive silanol end group. Polyethylene glycol molecular chains can store and release heat by switching between the crystalline and amorphous state. The silanol groups can form supramolecular networks through the physical cross‐linking of multiple hydrogen bonds, resulting in an excellent thermal stability. In particular, hydrogen bonds between ScPEG and AgNW‐modified GFF (A‐GFF) enhance interfacial interactions, and the resulting robust structure enables an efficient stress transfer. ScPEG‐coated A‐GFF can achieve a tensile strength of up to 191 MPa and a tunable EMI shielding effectiveness (SE) of 40 to 72 dB depending on the number of fabric layers. Moreover, the fabric exhibits a flexible thermal response characteristic, an outstanding thermal management capability, and potential message encryption behavior. [ABSTRACT FROM AUTHOR]

Thermoplastic polycarbonate provides minimal structural weight and ductility and is a recyclable material. However, investigation of the characteristics of hybrid composites reinforced with woven glass and polycarbonate sheets is limited. This current study investigated the effect of integration of polycarbonate sheets on glass fiber‐epoxy hybrid composite performance. Non hybrid laminate was fabricated from eight layers of woven glass fiber impregnated with epoxy resin (NG). However, the hybrid samples utilized various symmetric stacking patterns which were made by alternating two processed polycarbonate (PC) sheets with six layers of woven glass fiber embedded with epoxy matrix. The manufacturing was made using the hand layup procedure. Mechanical testing includes compressive, tensile, bearing, and hardness was performed on hybrid and non‐hybrid composites. The results showed that employing PC sheets instead of fibers affect the laminate's strength, ductility, bearing capacity, and hardness. Utilization of PC sheets reduces both compressive and tensile strength. However, an enhancement in tensile, compressive, and bearing failure strain was achieved by 2.5%, 31.25% and 31.7%, respectively with hybrid composite having PC in the skin layers as compared with NG. The extent of failure damage is correlated with the position of the PC sheets in the tested samples. Highlights: Novel hybrid composites of woven glass fiber and polycarbonate sheet as reinforcement with various stacking orders were successfully prepared by the hand lay‐up method.The compressive strain of hybrid PC samples are higher than NG sample.The hybrid PC composites showed an improved bearing strength and strain performance.The influence of sample configuration on the damage mechanisms has been investigated. [ABSTRACT FROM AUTHOR]

This study looks at how erosive wear affects hybrid composites made by vacuum infusing glass and basalt fibers into an epoxy matrix. The study uses garnet abrasives and a design experiment method to test how resistant these hybrid composites are to erosion at 30°, 60°, and 90° angles of impact. The analysis included three‐dimensional profilometry and scanning electron microscopy. Results show that glass layers enhance erosion resistance, whereas basalt layers increase wear. Key quantitative findings include erosion rates and mass loss, highlighting impingement angle and erosion time as critical factors. At a 30° angle, basalt exhibited more severe wear (erosion rate: 0.8090 mg/g for 20 s) compared to glass (erosion rate: 0.5683 mg/g). Conversely, at 90°, the erosion rate for basalt decreased to 0.3643 mg/g, indicating a decreased sensitivity to this steeper angle. According to the ANOVA, impingement angle and erosion time account for 30.08% and 50.25% of the erosion rate variance, respectively. These findings advance our understanding of material behavior in hybrid composites and emphasize the strategic selection and layering of materials for enhanced durability. This research contributes to developing more sustainable composites, demonstrating natural fibers' potential to improve mechanical properties and erosion resistance. Highlights: Glass layers enhance durability against erosive forces in hybrid composites.Basalt layers accelerate erosion rates, showing a need for strategic layering.Glass fiber reinforcement significantly improves wear performance.Hybrid constructions with glass a top basalt balance flexibility and durability.Emphasizes eco‐friendly advantages of natural materials in composites. [ABSTRACT FROM AUTHOR]

This research explores the scratch resistance of polymer composites reinforced with hybrid glass and basalt fibers under repeated loadings. By examining the behavior across 1–10 repetitions using Rockwell and Vickers indenters, the study delves into the complex interplay between composite matrices and the fibers' configurations. Through Scanning Electron Microscope (SEM) imaging and 3D profilometry, it reveals how different fibers influence the composite's surface post‐scratch tests. Basalt fibers are found to offer superior scratch protection over glass fibers, although both types' of effectiveness declines with increased loading cycles, showing significant material loss and surface damage respectively. Composites with these fibers display enhanced resistance, especially when basalt fibers are optimally positioned on the surface. The study underscores the critical role of fiber‐matrix bonding in scratch resistance and the significant impact of mechanical stress. It was found that the scratch hardness values reduced with more repeats in the scratch tests utilizing Vickers and Rockwell indenters. The sample with the label G4B6G4 has the greatest hardness values, which is noteworthy. After 10 repeats, the scratch hardness values for this sample reduced to 225 N/mm2 and 75 N/mm2, respectively, from roughly 340 N/mm2 and 225 N/mm2 at both ends for a single repetition. In addition, ANOVA for penetration depth is dominated (66.01%) by the repetition factor. The most common kind is indenter (42.79%), with low p‐values. Despite material and indenter effects, groove area study confirms the significance of repetition (65.72%). Highlights: Basalt fibers enhance scratch resistance more than glass fibers.Increased scratch repetitions lead to fiber breakage and material loss.Hybrid fiber layers distribute load and minimize surface damage.Strong fiber‐matrix adhesion is crucial for reducing damage severity.Research informs the design of durable, fiber‐reinforced composites. [ABSTRACT FROM AUTHOR]

The boundary condition is a very important factor when characterizing the impact performance of a material or a structure. However, its effect on fiber metal laminate (FML) has been rarely mentioned. In the present investigation, three levels of low‐velocity impact tests were conducted on the glass fiber reinforced aluminum laminate (Glare) under two different boundary conditions, one was that defined in ASTM D7136 and another one was self‐designed that has the same constraint area but different constraint degree. One basis of the experiments, finite element analyses were performed to gain a deeper understanding of the different damage mechanisms. With which another three boundary conditions were investigated for further considering the effect of constraint areas on both the impact and non‐impact sides, including that defined in another commonly used standard ASTM D5628 and two self‐designed cases. It was indicated that the boundary conditions influenced less the force and energy responses of Glare laminate, regardless of the impact damage levels, and hardly on the damage behavior as well when perforation was encountered. However, influences were obtained under lower and intermediate damage levels, and it was the constraint area on the rear side and constraint degree that played the dominant roles, respectively. The results achieved can provide suggestions for reasonably evaluating the low‐velocity impact performance of FML. Highlights: Comparisons were made between the low‐velocity impact behavior of Glare laminates under five different boundary conditions.Boundary conditions influenced hardly on maximum impact force and energy absorbed ratio, but evidently on damage behavior.Constraint area and constraint degree governed damage mechanism under lower and intermediate impact energies, respectively.Influence of boundary conditions on damage behavior disappeared when the impact energy was enough to perforate Glare laminate. [ABSTRACT FROM AUTHOR]

The reliable anchorage and long‐term durability of high‐performance fiber reinforced polymer composites were the decisive factors for engineering applications owing to the anisotropy of materials and the complexity of service environment. In this paper, an innovative glass fiber reinforced polypropylene (GFRPP) self‐anchor plate cable was developed to utilize the high toughness/durability of thermoplastic resin and self‐anchor load‐bearing system. The effects of different reinforcement methods and cable arc angles (10°, 20°, and 30°) on mechanical properties of plate cable were investigated. Water absorption behavior and mechanical properties immersed in alkali solution were tested to evaluate its long‐term service behavior. The thermogravimetric and surface morphology analysis were conducted to reveal the performance evolution mechanism. The results showed through the combination of secondary melting, carbon fiber winding confinement and epoxy reinforcements, the splitting failure of transition zone and interlaminar cracking failure of straight zone for plate cable were effectively avoided. The tensile strength retention of plate cable for arc angles of 10°, 20° and 30° were 45.6%, 41.3%, and 34.0% of GFRPP plate, respectively. Larger arc angle increased the curvature of arc‐straight transition zone and stress concentration near the straight section, leading to interlaminar splitting failure of plate cable at weak transition zone. The tensile strength of plate cable with the immersion time deteriorated obviously until the lowest retention of 29.7%. The degradation mechanism was mainly due to the etching of glass fibers in alkali solution and the formation of pores and internal defects, including fiber/resin interface debonding and resin swelling. The research results were of significance for solving the anchoring problems and promoting the long‐term service reliability in bridge applications. Highlights: The mold can realize reliable molding of glass fiber reinforced polypropylene cables after the reinforcements.The tensile strength retention of plate cable was up to 34.0%–45.6% of plate.Larger arc angle increased the stress concentration near the straight section.Non‐polar polypropylene plate was proved to have better hydrophobic performance.The degradation mechanism of plate cable in alkali solution was revealed. [ABSTRACT FROM AUTHOR]

Highlights Glass fiber reinforced polymer (GFRP) composites can be subjected to different environmental conditions such as temperature, humidity, ultraviolet radiation, hydrothermal cycle, acidic and alkaline solution in environments where they operate. These environmental conditions cause different damage mechanisms in composites such as pore formation, micro‐cracks, delamination, fiber breakage, fiber/matrix interface separation, plasticization, swelling and surface color change. In this study, wear properties of hybrid glass fiber reinforced polymer composites exposed to various environmental conditions for constant load (60 N), speed (500 rpm) and 2 h were examined comprehensively, depending on material content and environmental conditions. In this experimental study, the service conditions in glass fiber reinforced composites were simulated using different artificial aging environments such as acidic environment, hydrothermal cycle and UV radiation. In addition to the material content, it appears that the environmental conditions to which composites are exposed has a significant effect on friction coefficient. Considering environmental conditions, it is seen that the acid environment and hydrothermal cycle have reduced wear resistance of GFRP composites, while UV radiation improved wear resistance of the composites. In C2 sample, the wear rates under different conditions are 1.87 × 10−14 m3/Nm in non‐treated sample, 6.05 × 10−14 m3/Nm in acid environment, 4.79 × 10−14 m3/Nm in hydrothermal cycle and 0.59 × 10−14 m3/Nm in UV radiation. Friction coefficient of glass fiber reinforced polyester (GFRP) is higher under aged condition compared to non‐treated. Glass fibers used in correct proportions can reduce friction coefficient in GFRP. GFRP exposed to environmental conditions has an important effect on wear. Acid environment and hydrothermal cycle has reduced wear resistance of GFRP. UV radiation improved wear resistance of GFRP composite. [ABSTRACT FROM AUTHOR]

Reversible adhesives are crucial for a circular economy of composites as they play a key role for rework, repair, and recycling of adhesively bonded components. Herein, electrically debondable adhesives are prepared by introducing ionic liquids in dynamic thiol–epoxy networks. The function of the ionic liquid in the networks is threefold as it accelerates the curing reaction between thiol and epoxy monomers, facilitates electrical debonding, and catalyzes thermoactivated transesterification reactions, required for rebonding at elevated temperature. A library of 1,3‐dibutylimidazolium‐based ionic liquids with varying anions is synthetized and it is found that 1,3‐dibutyl‐1H‐imidazol‐3‐ium dicyanamide (DiButIm─N(CN)2) is superior in accelerating bond‐exchange reactions between hydroxy and ester moieties at elevated temperature. Thus, a thiol–epoxy resin containing 20 wt% of DiButIm─N(CN)2 is used to impregnate glass fiber mats yielding adhesive connections for aluminum substrates with 10.2 MPa pull‐off strength. The adhesive connections are successfully debonded at the metal–adhesive interface by applying 120 V. The samples are then rebonded via the thermoactivated change in the networks' viscoelastic properties and ≈80% (8.1 MPa) of their original bond strength can be regained. By providing a simple strategy to synthetize reversible adhesives, this approach paves a way toward improved recyclability and repairability of adhesively bonded structures. [ABSTRACT FROM AUTHOR]

Purpose: Additive manufacturing of polymer composites is a transformative technology that leverages the benefits of both composite material and 3D printing to produce highly customizable, lightweight and efficient composites for a wide range of applications. Design/methodology/approach: In this research work, glass fiber-reinforced polylactic acid (PLA) filament is used to print the specimen via fusion deposition modeling process. The process parameters such as infill densities (40%, 50% and 60%) and raster angle/orientations (0°, 45° and 90°) are varied, and the specimens for tensile, flexural, impact, hardness and wear testing are prepared as per their respective ASTM standards. Findings: The results revealed that with an increase in infill density, the mechanical properties of glass fiber-PLA specimens increase progressively. Optimal tensile properties and flexural properties are obtained at 0° and 90° raster angle orientations and 60% infill density. Minimum wear rate is achieved at 0° raster angle orientation and it increases at 45° and 90° raster angle orientations. Originality/value: Using SEM, the microscopic analysis of the fractured specimen was analyzed to study the interface between the fibers and matrix and it indicates the presence of good adhesion between the layers at 60% infill density and 0° print orientation. [ABSTRACT FROM AUTHOR]

There is a growing drive in replacing conventional non-renewable fibres such as glass and carbon reinforced composites with more sustainable and renewable reinforcements such as flax, hemp, jute in biobased composites in key industry sectors such as automotive, marine, building and construction motivated by lower carbon footprint and sustainability. Despite this drive, flammability characteristics of these sustainable biobased composites are not fully understood. Through an up-to-date review, this article meticulously discusses the theme of bio-based and eco-friendly flame retardants (FRs), delving into their intricate mechanisms, flammability testing methodologies, and emerging research trends. It underscores the pivotal necessity of developing tailor-made eco-friendly FRs customised for a diverse range of materials to bolster fire safety in sustainable material applications. Furthermore, it illuminates the limitations associated with prevalent methods for assessing flammability and advocates for advancements in dynamic testing and multi-scale analyses to more accurately simulate real-world fire scenarios. This review also highlights the key characteristics of natural plant fibres and their composites critical for the development of sustainable and fire safe materials for key applications areas. Additionally, it highlights the diverse spectrum of strategies employed in the realm of flame-retardant materials research, emphasizing a pronounced shift towards eco-friendly alternatives, innovative coatings, and the ongoing exploration of synthetic biopolymers, nanocomposites, and fibres in the pursuit of heightened fire safety. Amidst the inherent challenges, this comprehensive review unequivocally underscores the pivotal role of interdisciplinary research collaboration in driving forward fire safety within the domain of sustainable materials. [ABSTRACT FROM AUTHOR]

Background: This is an in-vitro study done to compare the effect of ferrule on fracture resistance of endodontically treated teeth restored with the glass fiber post cemented with two different esthetic resin modified cements Aim: To compare the fracture resistance of endodontically treated teeth restored with prefabricated glass fiber posts luted with two different resin cements. Materials and methods: Forty-eight freshly extracted maxillary central incisors of similar dimensions were used. The teeth were endodontically treated and decoronated to the level of the facial CEJ. The teeth specimens were divided into two groups of twenty-four each. In both the groups the Bioloren glass fiber posts were used. In Group 1 the posts were cemented with CALIBRA® esthetic resin system. In Group 2 the posts were cemented with SMARTCEMTM2. Cores were built using composite resin material. The teeth were then embedded in auto polymerizing acrylic resin blocks. The specimens were subjected to loading in a universal testing machine. The data obtained was subjected to statistical analysis. Results: The fracture resistance was higher for group 2 teeth with a mean ±SD of 2744±452.56340. The failure load observed in Group 1 was lower with a mean ±SD of 2178±452.56344. The one way ANOVA showed that in both the groups resin modified cements (Calibra ® esthetic resin cement and SmartCemTM2) highly significantly influenced the resistance of the specimen to fracture under static loading (P < 0.002 and P <0.001 respectively). Conclusion: The inherent strength of the SmartCem™2 enhanced stability and strength of the overall restoration when compared to Calibra ®. Further studies should incorporate thermal cycling of the specimen and cyclic loading, stress distribution patterns, photo elastic analysis, finite element analysis and model studies to achieve better results. [ABSTRACT FROM AUTHOR]

Cement, which is a significant constituent in concrete, plays a crucial role in the construction industry. The manufacturing process of cement releases substantial amounts of CO2, thereby contributing to environmental concerns. To address this issue, geopolymers have emerged as promising alternative substitutes to ordinary Portland cement. However, one of the challenges in utilizing geopolymer binders is the need for activators to initiate the polymerization process. Sodium silicate and sodium hydroxide solution are commonly used activators, but ground granulated blast-furnace slag (GGBS) reacts quickly with these activators and reduces the setting time. In order to arrest quick settings and enhance the efficiency of concrete production, "water glass" is used as an activator. The present study investigates the flexural and split tensile strength of geopolymer concrete by optimizing the dosage of polypropylene fibers for different mix proportions of GPC activated with water glass. The optimum dosage of fibers was obtained by the addition of different dosages of polypropylene fibers ranging from 0, 0.2%, 0.4%, 0.6% and 0.8%. The results from the investigation revealed a consistent augmentation in compressive strength with the incremental addition of fibers up to a threshold of 0.6%; beyond this point, the strength exhibited a dimin-ishing trend, while the flexural strength and split tensile strength were enhanced from 25% to 45% with the addition of an optimum dosage of polypropylene fibers. By optimizing the material formulations and mix proportions, it is possible to achieve a superior performance by minimizing the environmental impact on the construction industry. [ABSTRACT FROM AUTHOR]

The effects of geometric scaling on the strain rate sensitivity of unidirectional and [+45/−45]s laminates under uniaxial tensile loading has been investigated experimentally. Two material systems, Toray T800/3900-2B carbon/epoxy unitape and Newport NB321/7781 fiberglass/epoxy fabric, were used in the study. The nominal strain rates investigated ranged from quasi-static (0.0002 s−1) to moderate strain rates of 50 s−1 across the scaled specimen geometries. The geometric scaling effects at different strain rates were quantified in terms of the Weibull modulus. At each strain rate, the average failure stress of [0]4 carbon, [0]4 fiberglass, and [±45]s fiberglass showed a declining trend with increasing specimen size. However, the percentage of the strength reduction was less significant at higher strain rates compared to the quasi-static strain rate. In contrast to the other stacking sequences, [+45/−45]s carbon specimens showed a maximum percentage in strength reduction at a high strain rate compared to the quasi-static strain rate, indicating increased scaling effect with strain rate. The magnitude of Weibull modulus (m) for the specimens increased with strain rate indicating diminishing scaling effects, while [+45/−45]s carbon specimens exhibited an opposite trend. [ABSTRACT FROM AUTHOR]

This article investigates the eccentric ballistic impact response of square aluminum and fiber-metal laminated plates with the ANSYS AUTODYN hydrocode. The plates are impacted by a cylindrical projectile with normal high velocity. The validation of the numerical procedure is mainly carried out through comparisons with published experimental data. The modeling procedure and the verification of numerical results are described in detail so as to provide a useful reference. The effect of impact point eccentricity and different boundary conditions on the ballistic resistance of the targets is evaluated. It is found that the ballistic limits of the considered targets can be substantially affected by the boundary conditions and the eccentricity of impact. The targets are sorted in a descending order of ballistic resistance which is found invariant to the impact position. [ABSTRACT FROM AUTHOR]

Structural health monitoring (SHM) of composite materials is of great significance in various practical applications. However, it is a challenge to accurately monitor the damage of composites without affecting their mechanical properties. In this paper, an embedded sensing layer based on carbon nanotube-coated glass fiber is designed, combined with electrical resistance tomography (ERT) for in situ damage monitoring. Multi-wall carbon nanotube-coated glass fiber (MWCNT-GF) is prepared and embedded into laminates as an in situ sensing layer. Low-velocity impact experiments demonstrate that the embedded sensing layer has high compatibility with the composite laminates and has no adverse effect on its impact response; although, the energy absorption behavior of glass fiber-reinforced polymer (GFRP) laminates containing MWCNT-GF occurs about 10% earlier than that of GFRP laminates overall. ERT technology is used to analyze the laminates after a low-velocity impact test. The results show that the in situ monitoring method with the embedded MWCNT-GF sensing layer can achieve high precision in imaging localization of impact damage, and the error of the detected damage area is only 4.5%. [ABSTRACT FROM AUTHOR]

The primary characteristic of ablative materials is their fire resistance. This study explored the development of cost-effective ablative materials formed into application-specific shapes by using a polymer matrix reinforced with ceramic powder. A thermoplastic (polypropylene; PP) and a thermoset (polyester; UPE) matrix were used to manufacture ablative materials with 50 wt% silicon carbide (SiC) particles. The reference composites (50 wt% SiC) were compared to those with 1 and 3 wt% short glass fibers (0.5 mm length) and to composites using a 1 and 3 wt% glass fiber mesh. Fire resistance was tested using a butane flame (900 °C) and by measuring the transmitted heat with a thermocouple. Results showed that the type of polymer matrix (PP or UPE) did not influence fire resistance. Composites with short glass fibers had a fire-resistance time of 100 s, while those with glass fiber mesh tripled this resistance time. The novelty of this work lies in the exploration of a specific type of material with unique percentages of SiC not previously studied. The aim is to develop a low-cost coating for industrial warehouses that has improved fire-protective properties, maintains lower temperatures, and enhances the wear and impact resistance. [ABSTRACT FROM AUTHOR]

This study investigates the potential of natural fibers, commonly used as cost-effective fillers in the plastic industry, as replacements for glass fibers in composite materials. Despite their advantages, these natural fibers possess a strong polar nature, causing compatibility issues with certain thermoplastic platforms, particularly aromatic compounds. Surface-level treatments, though not cost-effective, offer a solution to this issue. This research focuses on optimizing and qualifying two treatment methods, the acetyl method and stearic treatment, applied to two types of flax fibers: long and short. Examining variables such as temperature, treatment duration, and compound recovery, this study employed diffraction and gas chromatography techniques to evaluate treated and untreated fibers. Results revealed that both treatments effectively reduced non-crystalline segments within the fibers, altering surface topography. Notably, the acetyl method increased fiber surface energy, while the stearic treatment decreased it. These findings underscore the significant impact of the acetyl method and stearic treatment on modifying fiber properties, particularly surface characteristics and energy levels. The study sheds light on the potential applications of these treatments in enhancing the compatibility of natural fibers with thermoplastic platforms, despite their inherent polarity. Incorporating visuals depicting the treatment processes would further enrich the study's authenticity and engagement, providing a tangible representation of the methods employed. [ABSTRACT FROM AUTHOR]

Thermoplastic composite pipe is gaining popularity in the oil and gas and renewable energy industries as an alternative to traditional metal pipe mainly due to its capability of being spooled onto a reel and exceptional corrosion resistance properties. Despite its corrosion-proof nature, this material remains susceptible to various defects, such as delamination, fiber breakage, matrix degradation and deformation. This study employed the phased array ultrasonic testing technique with the implementation of the classical time-corrected gain method to compensate for the significant spatial signal attenuation beyond the first interface layer in the thick multi-layered thermoplastic composite pipe. Initially, the ultrasonic signals from the interface layers and back wall were detected with good signal-to-noise ratios. Subsequently, flat-bottom holes of varying depths, simulating one-sided delamination, were bored and the proposed method effectively identified ultrasonic signals from these holes, clearly distinguishing them from the background noise and interface layer signals. Finally, a defect deliberately fabricated within the composite laminate layers during the pipe manufacturing process was successfully identified. Subsequently, this fabricated defect was visualized in a three-dimensional representation using the X-ray computed tomography for a qualitative and quantitative comparison with the proposed ultrasonic method, showing a high level of agreement. [ABSTRACT FROM AUTHOR]

Highlights Environmental hazards caused by the ever‐increasing end‐of‐life (EoL) glass fiber reinforced polymer (GFRPs) composite waste is of major concern for the sustainable development of the industry. Compared to land filling or incineration, pyrolysis is one of the most promising environmentally friendly methods of disposal of EoL GFRPs. Pyrolysis not only results in recovery of clean glass fibers but other valuable products, such as oils. However, long processing time at elevated temperature leads to aggravation of already existed surface flaws along with the structural changes. Therefore, thermal conditioning of glass fibers results in severe deterioration of the strength in recovered fibers and hence limiting the use of recovered fibers to low end‐products. In this study, a new strategy was adopted where instead of complete cleaning of the fibers at pyrolysis stage, the fibers were partially oxidized and the complete removal of char from the surface of glass was done during hot alkaline etching. This strategy was opted to enhance the quality of the required fibers while reducing the processing time. The results showed ~200% increase in strength of fibers after the combined treatment of pyrolysis and post etching compared to the just pyrolyzed samples with etching time of just 1 min. End‐of‐life panels of GFRPs were pyrolyzed under inert environment of Argon. Residual char was partially removed through post oxidation under flowing air. Hot alkaline etching resulted in complete removal of char and surface defects. Partial oxidation and short etching cycles resulted in improved strength of recovered glass fibers. [ABSTRACT FROM AUTHOR]

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This study investigated the effects of using bagasse ash (BA) and metakaolin (MK) together as substitutes for cement in self-compacting concrete (SCC), together with the addition of glass fiber (GF), on the physical and mechanical characteristics of concrete. Eighteen SCC mixes were created, each containing different proportions of BA (0%, 10%, 15%, and 20%), MK (0%, 10%, 15%, and 20%), and BA and MK collectively (10% + 5% and 10% + 10%) as cement replacements with and without 0.1% GF. Using the results of the slump flow, T500 slump flow, V-funnel, and L-box tests, the performance of fresh SCC was determined. Furthermore, this study evaluated the strength, durability, and microstructural properties of the SCC samples. The SCC mix blended with 10% BA and 5% MK revealed better flowability as the slump flow increased from 692 mm to 715 mm. A strong linear correlation was discovered between the slump flow values (mm) and V-funnel duration (sec) and blocking ratio (H2 /H1 ) with R² = 0.8876 and R² = 0.8467, respectively. Of all test mixes, the SCC mix blended with 10% BA, 5% MK, and 0.1% GF (SCC1B10M5) demonstrated the highest degree of strength. At 56 days, the 10% BA, 5% MK, and 0.1 GF mix had 12.8%, 25.7%, and 22.2% higher compressive, flexural, and splitting tensile strengths than the control mix, respectively. SCC, combined with BA, MK, and GF, outperformed the control mix. After immersion in a 3% H2SO4 solution, the SCC mix having 10% BA, 5% MK, and 0.1% GF experienced a minimum reduction in weight loss and ultrasonic pulse velocity of 1.01% and 3.1%, respectively. Additionally, there was a decrease of 29.4% in the percentage of charges passed. The ideal composition was achieved by incorporating 10% BA, 5% MK, and 0.1% GF into the SCC mixture, resulting in a dense structure without any visible pores or cracks during the microstructural analysis. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to compare the fracture strength and fracture modes of post-cores produced with CAD-CAM from modified polyetheretherketone (PEEK) materials with other custom-produced post-cores. Methods: Sixty human mandibular first premolars with equal root sizes were used. The teeth were divided into six groups (n = 10), and root canal treatment was performed. The teeth were separated from the roots over 2 mm from the cemento-enamel junction. As a result of the decoronation process, a 1 mm wide shoulder line was obtained for all teeth. For the fracture strength test, 10 mm deep post spaces were created on the teeth with a 1.6 mm diameter driller. Post-core groups consisted: everStick® glass fiber post-core (Group GF), zirconia post-core (Group Z), metal (Cr-Co) post-core (Group M), PEEK post-core without filler (Group UP), PEEK post-core with 20% TiO2 Filler (Group TP), and post-core with 20% ceramic filler (Group CP). Following the application of posts to post spaces, copings were created and cemented on the samples. With the universal tester, a force was applied to the long axis of the tooth with a slope of 135°. The mean fracture strength (N) between the groups was statistically evaluated using one-way ANOVA, and pairwise mean differences were detected using post hoc Tukey's HSD test among the groups. Results: According to the results of the statistical analysis, a significant difference was found between the groups in terms of mean fracture resistance (p < 0.05). Group Z (409.34 ± 45.72) was significantly higher than Group UP (286.64 ± 37.79), CP (298.00 ± 72.30), and TP (280.08 ± 67.83). Group M (376.17 ± 73.28) was significantly higher than Group UP (286.64 ± 37.79) and Group TP (280.08 ± 67.83). There were no statistically significant differences between the means of the other groups (p > 0.05). Among all the groups, Group Z exhibited a higher prevalence of repairable failure modes, while the rest of the groups predominantly experienced irreparable failure modes. Conclusion: In our study, zirconia and metal post-core samples showed higher average fracture strength values than PEEK post-cores groups. Repairable failure modes were more common in the zirconia post-cores, whereas the opposite was observed in the other groups. Further experimental and clinical trial studies are needed before PEEK materials can be used as post materials in the clinic. [ABSTRACT FROM AUTHOR]

The goal of this study was to determine the effect of cutting methods on the edges of selected materials applied in structural elements and floor sheathing of unmanned air vehicles. Three cutting methods for MGS L285 epoxy resin composites used for production of unmanned air vehicles manufactured in one of the European companies were presented. Composites reinforced by glass and aramid fibres are approved for certified production of air vehicle elements (AMC-20). Cutting was applied to each material using different technologies, such as: milling, laser cutting and abrasive water jet cutting. The authors focused on the edge quality of the tested specimens cut using various methods. Quality assessment was based on electronic microscopic scanning images and measurement of the specimen maximum damage. In summary, the choice of an appropriate composite cutting method depends on the type of material and its parameters, and it is crucial for the quality of the machined product. The authors focused on determining the selection of parameters for chosen cutting methods and materials used in the military unmanned aerial vehicle industry. Among the conducted tests, the results indicate that better cutting effects are obtained for milling methods in the case of GFRP + L285 (0.143 ± 0.073 µm) and CFRP + L285 (0.072 ± 0.027 µm), and the worst for AFRP + L285 (0.831 ± 0.269 µm). The water jet method gives the worst results in the cutting zone (results above 0.224 μm). [ABSTRACT FROM AUTHOR]

The 3D concrete printing (3DCP) technology is a rapidly developing and promising technique for creating concrete structures. One of the main challenges of the 3DCP technology is the method of reinforcement, which should be integrated with the automated printing process, while maintaining the best mechanical properties important for the strength of the structure. The main reason to undertake the subject is low degree of automation in construction industry, which results in high cost of human labour, as well as high rate of accidents in process. The article proposes a technology for automatic reinforcement of concrete structures with glass fibres and epoxy resin. Maximum bending force tests of the beams reinforced with the proposed method were carried out and compared with the beams reinforced with commonly used methods. Although not being an article focused on DIC analysis, several images were presented to compare the behaviour of non-reinforced beam with automatically reinforced one and to show cracking propagation of a chosen automatically reinforced beam. The proposed method of reinforcement in the 3DCP process enables full automation and constructions with high bending strength, simultaneously reducing the level of risk involved in conventional construction industry. [ABSTRACT FROM AUTHOR]

The work analyzes the fracture topography of composite specimens subjected to three-point bending - static and impact. Scanning electron microscopy was used for this purpose. The tests were performed for two different materials, namely polypropylene and polyamide PA6, each reinforced with unidirectional glass fibers. In one case, the fibers were distributed evenly, and in the other, there were areas more and less reinforced with fibers. It was observed that in all cases the tension and compression parts could be clearly distinguished. However, for different materials and with different methods of destruction, varying failure mechanisms were observed, noted based on the analysis of the fracture topography. It was observed that regardless of the loading method and material, in the tensile part there were visibly protruding fibers, and in the compressed part it was the matrix, rather than the fibers, that was destroyed. In the case of statically loaded samples, damage occurred at the macrostructural level, and in the case of dynamically loaded samples, at the microstructural level. Additionally, the samples with uneven fiber distribution were more susceptible to delamination. [ABSTRACT FROM AUTHOR]

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This paper presents a hermitic fiber sensor packaging technique that enables fiber sensors to be embedded in energy systems for performing multi-parameter measurements in high-temperature and strong radiation environments. A high-temperature stable Intrinsic Fabry–Perot interferometer (IFPI) array, inscribed by a femtosecond laser direct writing scheme, is used to measure both temperature and pressure induced strain changes. To address the large disparity in thermo-expansion coefficients (TECs) between silica fibers and metal parts, glass sealants with TEC between silica optical fibers and metals were used to hermetically seal optical fiber sensors inside stainless steel metal tubes. The hermetically sealed package is validated for helium leakages between 1 MPa and 10 MPa using a helium leak detector. An IFPI sensor embedded in glass sealant was used to measure pressure. The paper demonstrates an effective technique to deploy fiber sensors to perform multi-parameter measurements in a wide range of energy systems that utilize high temperatures and strong radiation environments to achieve efficient energy production. [ABSTRACT FROM AUTHOR]

One method to reduce power loss in wind power plants is by using a low-speed generator that can connect directly to a wind turbine without a gearbox. Low-speed generators require significant mechanical torque, necessitating the wind turbine to produce substantial mechanical torque at low speeds. This requirement can be met by increasing the number and size of blades. This paper proposes a low-speed horizontal-axis wind turbine (HAWT) designed to generate substantial mechanical torque, thus suitable for low-speed generators without gearboxes. The HAWT features six fiberglass blades shaped in a NACA 6412 airfoil. Performance evaluation of the HAWT is based on tip speed ratio (TSR) and power coefficient. The turbine's characteristics were experimentally investigated using a low-speed permanent magnet generator (PMG), a boost converter, and an Arduino Uno controller. Parameter values were observed by testing, the HAWT under varying wind speeds and rotor rotation speeds. Wind speed variation was achievedis varied using a blower, while rotor speed was controlled via a boost converter controlled by an Arduino. Experimental results demonstrate the suitability of the HAWT for its intended purpose, achieving. a maximum power coefficient of 0.34 and an optimum TSR of 5.2. [ABSTRACT FROM AUTHOR]

Copyright of Materiały Budowlane is the property of Wydawnictwo SIGMA-NOT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the aid of 3D printing, this study attempts to calculate the effective elastic modulus as well as the dimensional correctness and porosity of bolt samples. The main contribution of this study is the identification of the bolt sample porosity that is most appropriate for use as cancellous bone implants. It was discovered by contrasting the printed bolt sample's size, porosity, and effective modulus of elasticity with cancellous bone, as well as with the CAD model. This study examines the characteristics of bolt PLA samples created using SolidWorks software and manufactured in three dimensions using FDM. Observing the uniaxial tensile and determining its elasticity using stress-strain curves were the goals. Three of the five bolt samples used in the tests yielded essentially accurate results. Our research will aid in comprehending numerous facets of creating, testing, and optimising 3-D printed PLA bolts for use in real-world applications. The effective modulus of elasticity is generated by computer simulation using the MSC Marc software. Bolts with porosity variations of 42.9 percent and 58.1 percent revealed that the results of the printed bolt were flawless, but those with porosity variations of 22.3 percent and 73.4 percent generated incorrect impressions because they had too few pores or features. However, bolts with porosities of 58.1 and 73.4 percent exhibited a suitable elastic modulus that matched the span of cancellous bone. The bolt with a porosity of 58.1 percent was found to be the most suitable for usage as a cancellous bone implant with precise fabrication results. [ABSTRACT FROM AUTHOR]

This study was focused on developing and evaluating the impacts of wood and graphite fillers on an E-glass fibre-reinforced polyester composite. The fillers employed in this study include teak, casuarina, psuedon wood dust, graphite, and hybrid fillers such as casuarina and graphite fillers. They tested for tension, flexural, impact, hardness, and dynamic mechanical analysis. In the current work, the optimum loading level is 15 wt% which was determined through testing at various loading levels. The experimental results have shown that the mechanical, physical, and thermomechanical properties of glass fiber reinforced polyester composites improvement mechanism analysis depend upon chemically treated wood dust fillers by avoiding surface delamination during fabrication. By using the hand layup method, composites were created by maintaining the fibre constant while distributing the fillers following the rule of mixture; a hybrid composite has a filler distribution of 1:1. Hybrid composite has exhibited increased flexural strength and hardness by 72.77%, 63.33% compared to casuarina wood of 15 wt% by avoiding incompatibility of casuarina wood filler with the resin. The glass transition value of the hybrid composite was increased by 1.4% compared to the above said casuarina wood composite, making it a more thermally resistant material. The hardness of the hybrid composite has increased by 2.78% compared to the teak wood of 15 wt% composite. [ABSTRACT FROM AUTHOR]

The separator is an essential component of sodium‐ion batteries (SIBs) to determine their electrochemical performances. However, the separator with high mechanical strength, good electrolyte wettability and excellent electrochemical performance remains an open challenge. Herein, a new separator consisting of amphoteric nanofibers with abundant functional groups was fabricated through supramolecular assembly of natural polymers for SIB. The uniform nanoporous structure, remarkable mechanical properties and abundant functional groups (e.g. −COOH, −NH2 and −OH) endow the separator with lower dissolution activation energy and higher ion migration numbers. These metrics enable the separator to lower the barrier for desolvation of Na+, accelerate the migration of Na+, and generate more stable solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI). The battery assembled with the amphoteric nanofiber separator shows higher specific capacity and better stability than that assembled with glass fiber (GF) separator. [ABSTRACT FROM AUTHOR]

Resin bond grinding wheels are the most common grinding tools in the industry. Until now, all research on the additive manufacturing of resin bond grinding wheels has focused on commercially available acrylate resin. However, using a phenol-based bond to print resin-bond grinding wheels has been challenging for researchers and industries. In this study, a photo-curable phenol resin bond grinding wheel was introduced for the first time, offering advantages such as lower cost, high thermal resistance, and good mechanical properties. To enhance the grinding performance of the printed wheels, various additives, such as copper, glass fiber, and carbon fiber, were incorporated into the composition. Different on-machine and out-of-machine measurements, such as force, tool wear, dimensional accuracy, and optical microscopy measurements, were conducted to investigate the grinding performance of the printed wheels. The results demonstrate that printed grinding wheels have strong potential in grinding applications, which was more prominent for the bond reinforced by glass fibers, providing improved mechanical properties (up to 50%), wear resistance (up to 75%), and higher dimensional accuracy (up to 11%). [ABSTRACT FROM AUTHOR]

A straightforward mixing approach that involves incorporating glass fiber into cement-based materials is frequently carried out at construction sites. This practice can have adverse effects on both the fresh and hardened properties of cement mixtures. The lack of quality control measures often leads to the production of fiber-reinforced cement mixtures that do not perform as intended. Additionally, the inherent variations in commercially available glass fibers of the same type add complexity to mixing, making it difficult to consistently reproduce desired effects for in situ casting. Therefore, this research aims to accomplish three main objectives. Firstly, characterizing E-glass and AR-glass fibers to enable a practical replication of performance using these specific variants. Secondly, assessing the impact of five different mixing methods on water absorption, flowability, setting time, compressive, and flexural strength in cement mixtures embedded with these glass fibers. Lastly, evaluating the fiber-matrix interaction within the hardened samples for each mixing method. The results revealed that various mixing methods yielded distinct advantages in the fresh and hardened properties. This highlights the variability in mixing approaches, indicating that the choice of method should be tailored to meet the specific construction requirements of engineers. In essence, the study underscores the importance of selecting an appropriate mixing technique based on the desired outcomes for both the fresh and hardened states of cement mixtures. [ABSTRACT FROM AUTHOR]

As an environmentally friendly and renewable energy solution, wind power is rapidly gaining favour worldwide due to its gentle impact on the environment. Nevertheless, the potential environmental risks posed by discarded wind turbine blades still need to be brought to our attention. Therefore, exploring ways to recycle and reuse discarded wind turbine blades has become an urgent task in the field of environmental protection. This study focuses on the incorporation of recycled glass fibres from crushed wind turbine blades into concrete to assess their benefits in engineering practice. In this study, we used four different particle sizes of recycled glass fibres, 0-5mm, 5-10mm, 10-15mm and 15-20mm, and incorporated them into the concrete at four different admixture levels of 0.2%, 0.4%, 0.6% and 0.8%. By comprehensively examining its workability, mechanical properties and microstructure, we found that although the incorporation of glass fibres reduced the apparent density, slump and compressive strength of the concrete to a certain extent, it significantly improved the split tensile and flexural strengths of the concrete, as well as effectively improved the brittleness of the material and enhanced its toughness. These findings reveal the feasibility of recycling glass fibres from decommissioned wind turbine blades and applying them to concrete. This study not only opens up a new path for environmentally friendly recycling and reuse of wind turbine blades, but also provides a valuable reference for practical engineering applications, with significant social and economic benefits. [ABSTRACT FROM AUTHOR]

The aim of the study was to experimentally verify the enhancement of certain mechanical properties of a composite material consisting of unsaturated polyester matrix reinforced with fiberglass, by incorporating specific proportions of sodium aluminosilicate (SAS) powders and talc as fillers for the fabrication of large wind turbine blades. Samples composed of these materials, with varying combinations of the added components, underwent testing for tensile and bending strength, and experiments were conducted to determine their modulus of elasticity. The findings indicate that the inclusion of SAS in the matrix material resulted in increased values of tensile strength and modulus of elasticity up to certain proportions. Solely adding talc to the matrix material led to a rise in bending strength. Increasing the talc percentage in the matrix material reinforced with 20% fiberglass resulted in decreased tensile strength and elastic modulus of the samples, while incorporating a blend of SAS and talc into the matrix material reinforced with 20% fiberglass significantly boosted the elastic modulus and tensile strength of the samples under tensile conditions. [ABSTRACT FROM AUTHOR]

The paper presents a study on the stresses and deformations induced by the transversal loading of some flat plates made of E Glass EWR Fiberglass Woven Roving type, having delamination type defects. The parametric analysis of the delamination influence on the stresses and displacements occurring in the plate material is performed. The results of the static calculation are compared with the experimental tests of the flat plates subjected to bending, highlighting the concordance of the variation of the stresses and displacements versus to the delamination position. [ABSTRACT FROM AUTHOR]

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

Three‐dimensional (3D) printing, or additive manufacturing (AM), is rapidly advancing, allowing for the creation of objects from a digital model through the successive addition of materials. Among the AM techniques, fused deposition modeling (FDM) emerges as one of the most promising and extensively utilized methods. However, the inherent mechanical shortcomings of the deposition of pure thermoplastic materials necessitate the improvement of mechanical properties. One viable approach involves integrating reinforcing fibers into the thermoplastic matrix to create polymer composites suitable for structural applications. In this study, the mechanical properties of acrylonitrile butadiene styrene (ABS) reinforced with short glass fibers (SGFs) printed by FDM were investigated. The aim was to explore the impact of process parameters, including nozzle temperature, number of shells, and print speed, on the tensile properties and interlaminar shear strength (ILSS). Composite filament with 10% weight fraction (10 wt%) of glass fiber fabricated. Also, the mechanical properties of the composite and pure polymer were investigated. The length of the fibers was measured after the extrusion and printing process, revealing that they had been damaged. The shells exerted the most significant influence on test outcomes. [ABSTRACT FROM AUTHOR]

The hybridisation of fibre-reinforced polymers (FRPs), particularly with the combination of natural and synthetic fibres, is a prominent option for their development. In the context of the construction industry, there is a notable gap in research on the use of jute and glass fibres for the strengthening of concrete structures. This paper presents comprehensive experimental results from tests on seven reinforced concrete (RC) beams strengthened for shear using synthetic, natural, and hybrid jute–glass FRP composites. The beams were reinforced using the externally bonded reinforcement (EBR) technique with U-wrap bonding. A beam without any strengthening was tested and set as a reference for the other beams. Two beams were tested with synthetic FRP shear strengthenings, one with carbon fibre-reinforced polymer (CFRP) and another with glass fibre-reinforced polymer (GFRP). The remaining tests were on RC beams strengthened with natural jute fibre-reinforced polymer (JFRP) and hybrid jute–glass FRP. The paper discusses the experimental behaviour of the tested beams in terms of vertical displacements, crack widths, and strains on steel bars, concrete, and FRP. The experimental strengths are also compared with theoretical estimates obtained using ACI 440.2R and fib Bulletin 90. The tests confirm the effectiveness of natural jute FRP and jute–glass hybrid FRP as an option for the shear strengthening of reinforced concrete beams. [ABSTRACT FROM AUTHOR]

Cracks in asphalt mixtures compromise the structural integrity of roads, increase maintenance costs, and shorten pavement lifespan. These cracks allow for water infiltration, accelerating pavement deterioration and jeopardizing vehicle safety. This research aims to evaluate the impact of synthetic fibers, specifically glass fiber (GF) and polypropylene fiber (PPF), on the crack resistance of Hot-Mix Asphalt (HMA). An optimal asphalt binder content of 5% was used in all sample designs. Using the dry mixing technique, GFs and PPFs were incorporated into the HMA at dosages of 0.50%, 1.00%, and 1.50% by weight of the aggregate. The effects of these fibers on the mechanical fracture properties of the HMA were assessed using Semi-Circular Bending (SCB), Indirect Tensile Asphalt Cracking Tests (IDEAL-CTs), and Three-Point Bending (3-PB) tests. This study focused on fracture parameters such as fracture work, peak load, fracture energy, and crack indices, including the Flexibility Index (FI) and Crack Resistance Index (CRI). The results from the SCB and IDEAL-CT tests showed that increasing GF content from 0.5% to 1.5% significantly enhances the flexibility and crack resistance of HMA, with FI, CRI, and CT Index values increasing by 247.5%, 55%, and 101.35%, respectively. Conversely, increasing PPF content increases the mixture's stiffness and reduces its crack resistance. The PP-1 mixture exhibited higher FI and CT Index values, with increases of 31.1% and 10%, respectively, compared to the PP-0.5 mixture, based on SCB and IDEAL-CT test results. The SCB, IDEAL-CT, and 3-PB test results concluded that fibers significantly influence the fracture properties of bituminous mixtures, with a 1% reinforcement dosage of both PPFs and GFs being optimal for enhancing performance across various applications. [ABSTRACT FROM AUTHOR]

High‐performance engineering thermoplastics are important emerging materials, particularly when processed using additive manufacturing technologies. One of the most important among these is polyetherimide, also known as PEI or ULTEM. Using the fused filament fabrication (FFF) additive manufacturing (AM) process to form this material is a good option, but it is difficult to control the properties in some cases due to the very high processing temperature compared with most engineering thermoplastics. One way to "even‐out" the properties is to wrap the specimens in continuous glass or carbon fibers embedded in a thermosetting matrix, as this allows strategic placement and orientation of reinforcement. This also complements the natural structure of the FFF‐manufactured materials, helping to minimize the amount of additional weight that needs to be added to a part. To further knowledge in this area, the present study explored and compared the interlaminar tensile strength of FFF‐processed PEI/ULTEM 9085 specimens and compared them with ones wrapped in carbon fibers with a 2‐part resin matrix. Experiments were performed in accordance with the guidelines given in the ASTM D6415 standard and replicated five times. Variations were introduced in thickness of the specimen and raster angle during the manufacturing process to identify the significant impact of the failure. The results show a fall in interlaminar tensile strength with increasing specimen thickness and a very large effect from natural printing defects in the samples. The carbon fiber wrap decreased the ILTS but made the results far more consistent between experimental runs. This study provides a good, replicated dataset on the performance of raw and fiber‐wrapped FFF‐processed ULTEM 9085 and gives insights into the structural behavior of the material that will be useful for use in design decisions and material selection. Highlights: Polyetherimide, also known as PEI/ULTEM, is a high‐performance engineering thermoplastic.Explored the interlaminar tensile properties (ILTS) of this material using ASTM D6415.Raster angle, thickness, and use of fiber wrap were experimental parameters.Fiber wrap was found to have little effect on strength but made results more consistent.Results are useful for material selection and design decisions using PEI. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the far field function of electric field, a new glass carbon fiber gradient-stitched structure is proposed and designed in the paper. In the frequency range of 8–28 GHz, the electric field distribution of transverse electric and magnetic field (TEM) waves incident obliquely on the surface of the structure by optimizing the glass fiber fabric units. It is confirmed that the surface has the function of suppressing electromagnetic wave reflection. The electrical performance simulation and testing results of the structure show that the radar cross section (RCS) is reduced by 90% in the frequency range of 12.3–26.5 GHz. In addition, a multi-scale analysis model is established to quickly predict the tensile modulus and strength of the composite material. The strength and modulus reached 26.9 GPa and 403 MPa, respectively. The simulating and testing results of mechanical properties are in good agreement. [ABSTRACT FROM AUTHOR]

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

Leaf springs are designed to bear loads as well as shocks in automotive vehicles. Two leaves of glass fiber-reinforced composites (GFRCs) of various shapes sandwiched between steel plates were analyzed for application in a minitruck. Computer-aided engineering analysis was performed for five different types of GFRC material leaf springs: flat leaf, flat and parabolic leaf, both parabolic leaf, both parabolic leaf springs with aluminium alloy bushes at the eye-end and spring steel multi-leaf springs. A silencer pad was used in the parabolic leaf spring to reduce delamination and vibration at contact points of the mating leaf. The various shapes and combinations of leaves provided varying parameters, namely, the deformation, maximum equivalent strain, maximum equivalent stress and fatigue life. The CAE results showed that compared with the other combinations, the flat leaf and parabolic leaf combinations provided the maximum equivalent strain, maximum equivalent stress and fatigue life. [ABSTRACT FROM AUTHOR]

Highlights Additive manufacturing has enhanced the production of complex parts with greater efficiency. However, inherent drawbacks such as reduced mechanical properties still pose challenges, necessitating further improvements to bridge the gap and meet industry demands. Therefore, this study investigated the use of glass fiber woven fabric with vat‐photopolymerization printing to achieve composite parts with superior mechanical properties. This approach offered an advantage in reducing the production time required for fiber‐reinforced composites by eliminating the need for curing processes or vacuum infusion. The mechanical properties of the composite panels manufactured with this method were investigated using flexural, interlaminar shear (ILSS), impact tests with different fiber orientations, and fiber volume fractions. The results of the mechanical tests showed maximum flexural strength of 295 MPa, impact strength of 174 kJ/m2, and ILSS of 20.58 MPa. In addition, optical images were taken to examine the cross‐section of the printed parts, which revealed a uniform and good wetting of the fibers. The findings suggest that glass fiber woven fabric in vat printing is a promising approach for producing composite parts with enhanced mechanical properties and reduced production rate. Additive manufacturing of glass fiber woven fabric reinforced with VPP printing. Reduced production time and microstructure by using layer‐by‐layer manufacturing. Maximum flexural strength: 295 MPa, impact strength: 174 kJ/m2, ILSS: 20.58 MPa. Consistent porosity values with the increasing number of layers. Promising for producing standard and thick composites with improved properties. [ABSTRACT FROM AUTHOR]

Polymer electrolytes play a crucial role in advancing rechargeable magnesium batteries (RMBs) owing to their exceptional characteristics, including high flexibility, superior interface compatibility, broad electrochemical stability window, and enhanced safety features. Despite these advantages, research in this domain remains nascent, plagued by single preparation approaches and challenges associated with the compatibility between polymer electrolytes and Mg metal anode. In this study, we present a novel synthesis strategy to fabricate a glycerol α,α′‐diallyl ether‐3,6‐dioxa‐1,8‐octanedithiol‐based composite gel polymer electrolyte supported by glass fiber substrate (GDT@GF CGPE) through anion modification and thiol‐ene click chemistry polymerization. The developed route exhibits novelty and high efficiency, leading to the production of GDT@GF CGPEs featuring exceptional mechanical properties, heightened ionic conductivity, elevated Mg2+ transference number, and commendable compatibility with Mg anode. The assembled modified Mo6S8||GDT@GF||Mg cells exhibit outstanding performance across a wide temperature range and address critical safety concerns, showcasing the potential for applications under extreme conditions. Our innovative preparation strategy offers a promising avenue for the advancement of polymer electrolytes in high‐performance rechargeable magnesium batteries, while also opens up possibilities for future large‐scale applications and the development of flexible electronic devices. [ABSTRACT FROM AUTHOR]