Glass Fiber Research Articles

Tensile and Impact Properties of Woven Glass Fibers/Epoxy Composites Filled with Short Glass Fibers

Glass fiber/polymer composites are widely utilized in many structural applications because of their high specific strength and stiffness-to-weight ratios. In this study, woven glass fiber/epoxy was hybridized with short glass fibers of different lengths (2, 4, 6, 2+4, 2+6, and 4+6 mm) and contents (3, 6, 9, and 12 wt%) to produce hybrid woven SGF/epoxy composites. Variations in the thickness, fiber volume fraction, density, and void content of the prepared composites were determined. Mechanical tests such as tensile and Charpy impact tests were conducted. Compared to the woven fabric composites without short glass fibers (control samples), the tensile strength increased by approximately 13% at an optimum weight fraction of 3 wt% using short glass fiber lengths of 4 mm. Meanwhile, the incorporation of short glass fibers into the woven glass composites decreased the tensile modulus for all lengths. The maximum enhancement in the impact strength (approximately 14%) was achieved by the hybrid composite samples reinforced with 4 mm of short glass fibers at 3 wt%. This hybrid composite offers 18% and 20% improvements in the specific tensile and impact strengths, respectively. In summary, filling the woven fabric composites with specified short fiber contents and lengths can increase their mechanical performance when resin-rich regions are reinforced with short fibers without forming relatively thick interleaves between the woven fabric plies

Fracture resistance of postendodontic restoration using self-adhesive bioactive resin and a bulk-fill composite with or without resin-impregnated glass fibers: An in vitro study.

Due to advancements in adhesive technology and the introduction of fiber reinforcement, there has been a paradigm shift towards a more minimally invasive approach in coronal restoration of endodontically treated teeth. This research aimed to evaluate and compare fracture resistance of postendodontic restoration using a self-adhesive bioactive resin and a bulk-fill composite with or without resin-impregnated glass fibers. Mesio-occlusal-distal cavities were prepared on 80 extracted human maxillary premolars. Root canal treatment was completed following standard access cavity preparation. Then, the teeth were divided into two groups based on the composite used for postendodontic restoration. Group I: Bulk-fill composite (Tetric N-Ceram). Group II: Activa BioActive. Group I and Group II were then divided into two subgroups depending on fiber incorporation (n = 20). Subgroup IA: Bulk-fill composite. Subgroup IB: Bulk-fill composite with fiber incorporation. Subgroup IIA: Activa BioActive. Subgroup IIB: Activa BioActive with fiber incorporation. The force required to fracture the teeth was recorded using the universal testing machine. Two-way ANOVA and Tukey's multiple post hoc test. Activa BioActive with fiber incorporation showed the highest mean fracture resistance (988.52N). Bulk-fill composite without fiber incorporation had the least mean fracture resistance (669.87N). Activa BioActive bulk-fill restorative material when used with the incorporation of resin-impregnated glass fibers can be a preferred material of choice for restoring endodontically treated teeth.

Clinical Performance of Short Fibre-reinforced Glass Ionomer Cement Restorations in Cervical Carious Lesions: 12-Month Randomized Clinical Trial.

The aim was to assess the clinical performance of experimental short fiber-reinforced glass-ionomer cement (FR-GIC) in the treatment of cervical caries lesions. A total of 45 patients were randomly enrolled in this trial according to the split-mouth design. The FR-GIC was prepared by adding short glass fibers at a mass ratio of 20% into the powder portion of Fuji II LC. The cervical lesions in the intervention group were restored with FR-GIC, while unmodified Fuji II LC was applied as the control. Clinical evaluation was performed by two blinded operators at baseline, at 6, and 12 months using modified USPHS criteria. The data were analyzed using Friedman's test, followed by the Nemenyi post hoc test with a significance level of α = 0.05. After 1 year, all restorations were fully retained. There was no statistically significant difference (p⟩0.05) between the two materials based on the evaluated criteria. Both groups had 4 (10%) cases with Bravo scores for cavos-surface marginal discoloration. Regarding marginal integrity, Bravo scores were observed in 5 (12.5%) cases in the intervention group and 4 (10%) cases in the control group. Both materials in the treatment of cervical caries lesions demonstrated satisfactory clinical outcome throughout the 12-month follow-up.

Glass fiber-based metal organic gel composite electrolytes for solid-state lithium batteries

Abstract Quasi-solid-state electrolytes encounter great obstacles in structural stability due to their inherent heterogeneity. Here, we introduce a new composite structure of glass-fiber-based metal-organic gel as a solid-state electrolyte and explore its electrochemical properties in lithium-metal batteries. We use a straightforward in-situ sol-gel method to synthesize this composite electrolyte, where glass fiber acts as matrices, ferric nitrate reacts with trimeric acid to form interconnected channels with abundant unsaturated metal sites, while ionic liquid electrolyte is in-situ confined into interconnected channels. The as-prepared composite electrolyte membrane has a uniform structure and composition, exhibiting a high room-temperature ionic conductivity of 1.79×10−3 S cm−1 and a high electrochemical oxidation potential of 4.76 V vs Li/Li+. This composite has excellent cycling performance in LiFePO4//Li (99.5% after 100 cycles) and NCM811//Li (86.6% after 200 cycles) batteries.

Synthesis of quaternized glass fiber filter and study on its adsorption for Pu (IV)

In this study, a novel pretreatment material was developed for the separation of trace plutonium (Pu) in complex systems. Glass fiber filters, known for their resistance to chemical corrosion, radiation and thermal stability, were used as the base material for separation and enrichment. However, the number of active groups on the surface of the matrix material was limited, resulting in poor chemical grafting efficiency. To address this, a new method is proposed involving deposition and chemical grafting. A polydopamine coating was formed on the filter surface through the oxidation and self-polymerization reaction of dopamine. Subsequently, the coupling agent chloromethyltrimethoxysilane and the extraction agent trioctylamine were employed to quaternize the glass fiber filter, resulting in the synthesis of a novel pretreatment material. Various characterization techniques were employed to investigate the morphology and surface functional group structure. Finally, the material was applied in the adsorption of trace plutonium, and the adsorption performance and mechanism for plutonium (IV) (Pu4+) were explored. The adsorption results indicated that when the nitrate acidity was 4 mol/l, the adsorption capacity of the material reached its maximum value. The adsorption capacity reached equilibrium within 360 s. The maximum adsorption capacity of GF-PD-CTS-TOA for plutonium (IV) was 20.35 mg/g (0.085 mmol/g). Complex anions Pu(NO3)6 2− and Pu(NO3)5 − were the main forms of plutonium (IV) adsorption. This is the first time that this method was used to modify glass fiber filters, and this study represents the first application of functionalized glass fiber filters in the analysis and separation of radioactive elements during reprocessing.

Flexible and anisotropically conductive film by assembly of silicone rubber and cobalt-coated glass fiber composites

In this study, we prepared electromagnetic cobalt-coated glass fiber (Co@GF) composites via an electroless plating method. Subsequently, a conductive sandwich flexible film consisting of Co@GF composites and liquid silicone rubber (RTV-2) was successfully formed using the tape casting method at room temperature. Based on the perfect coating and excellent electrical conductivity of the Co@GF composites, the resultant RTV-2/Co@GF/RTV-2 sandwich flexible film showed a low volume resistivity of 0.264 Ω·cm and could stretch to 100% (of 4.40 Ω·cm) without obvious fracture. When a magnetic field was applied during the curing process, the electromagnetic Co@GF composites were aligned automatically in the RTV-2 matrix because of their ferromagnetic nature. The as-prepared film exhibited anisotropy in its electrical performance. The volume resistivity parallel to the magnetic field direction is approximately two times lower than that in the perpendicular direction. The maximum difference in the volume resistivity (ρ∥ = 0.768 Ω·cm and ρ⊥ = 1.549 Ω·cm) was obtained at a magnetic field intensity of 800 mT. In addition, a magnetic field intensity of 100 mT helps improve the electrical conductivity of the as-obtained sandwich film. The anisotropic RTV-2/Co@GF/RTV-2 sandwich flexible film is considered a promising flexible electronic sensor, where discrepant inductive sensitivity is required in orthogonal directions.

The impact of various curing methods on the curing process of polymer-fiber composites analyzed using analytical approach

Ti/Gf/Cf represents a novel form of hybrid fiber metal laminates (HFMLs) that successfully blend the benefits of titanium alloy, glass fiber reinforced plastic (GFRP), and carbon fiber reinforced plastic (CFRP). These materials have garnered attention in the field of engineering due to their exceptional levels of stiffness, strength, and shear resistance. The quality of HFMLs during the curing process was significantly impacted by the chosen curing method. Moreover, the use of multiple types of fibers complicated the optimization of curing parameters in HFMLs. A comprehensive study was conducted using a multi-physics field coupling finite element method to investigate the impact of various curing methods on the development of temperature distribution, curing degree, and curing stress in HFMLs during the curing process. By integrating thermal transmission equations, curing kinetics, and viscoelastic mechanical models, a detailed curing simulation model was established. Increasing the cooling rate from 1 °C to 5 °C was shown to raise the maximum curing stress by 4.7 MPa. Additionally, higher curing temperatures were found to induce internal curing stress due to variations in thermal properties. Insufficient insulation times were observed to exacerbate non-uniform temperature distribution and curing degree fields in HFMLs, potentially leading to increased internal stress. To mitigate the generation of large residual stress, it is recommended to lower the heating and cooling rates, reduce curing temperatures, and extend the insulation time appropriately during the curing process of HFMLs. The primary goal of this research was to accurately predict the evolution of curing parameters in HFMLs under different curing regimes, which were impacted by the chosen curing method. The results of the study demonstrated that rapid changes in temperature during heating and cooling stages can lead to uneven curing, resulting in the accumulation of residual stress within the laminates.

Influence of Battery Levels in Cordless LED Light-curing Units on Properties of Resin Cement and Glass Fiber Post Retention.

This study aimed to assess the impact of battery levels in single-peak and multi-peak light-curing units (LCUs) on irradiance, and their effects on glass fiber post push-out bond strength to root dentin and the degree of conversion of dual-cure universal resin cement. Sixty bovine roots underwent endodontic treatment and were randomly distributed into 6 groups (n=10), formed by combining two LCUs (single-peak and multipeak) and three battery levels (100%, 50%, and 10%). A spectrophotometer measured irradiance (mW/ cm2) and spectral irradiance (mW/cm2/nm). Push-out bond strength (PBS) tests occurred at three root regions (cervical, middle, and apical), with optical and scanning electron microscopy for failure mode analysis. Degree of conversion (DC) was evaluated across the root regions. Data were analyzed using two-way repeated measures ANOVA and the Tukey HSD test. The Fisher exact test verified failure modes (α=0.05). As multipeak LCU battery levels decreased, emitted irradiance also diminished, with notable PBS reductions in the apical thirds. Failure modes were influenced by different conditions, primarily exhibiting mixed modes. Battery levels significantly impacted DC in the multipeak LCU, particularly in the cervical region, while the single-peak LCU exhibited DC reduction at the 10% battery level in the cervical region. Emitted irradiance, resin cement DC, and glass fiber post bond strength to root dentin may be influenced by varying cordless LCUs and battery levels.

Improving performance of GFRP joints using bolted/mortise-tenon hybrid method

Abstract In this study, the effects of different connection methods such as adhesives and bolts on the performance of GFRP joints were compared. A hybrid method based on bolted/mortise-tenon was proposed, and the static strength of joints was studied through experiments and numerical simulations. Static trength testing using glass fiber reinforced polyurethane composites. The results showed that for adhesive-bonded joints, double-lap shear specimens have the highest shear strength. For bolted joints, double-lap specimens also have higher connection strength than single-lap specimens. And the strength of joints using bolts is much greater than that using adhesives. In addition, the bolted/mortise-tenon hybrid joint has a self-locking structure of dovetail and tenon connections, which converts shear strength into structural strength, effectively improves the load-bearing capacity, increases the reliability of the connection, and contributes to higher load-bearing capacity.

Comparison of mechanical behavior of slabs reinforced with GFRP and steel

The objective of this study is to evaluate the mechanical behavior of GRFP in massive concrete slabs. The use of glass fiber reinforced polymer (GFRP) rebars in construction design has been an alternative technique to provide more durable structures. However, there is a need to evaluate the behavior of GFRP reinforced slabs under flexure and to compare the service state (SS) and ultimate service state (USS) of the loaded element. Thus, reinforced concrete slabs of varying thicknesses were constructed with steel and GFRP rebars. Results show that the applied load for maximum span deflection of the GFRP slab under SS was 50% lower than for the one with steel reinforcement. The maximum span deflection of the GFRP slab under USS was also 282% larger than for steel rebars reinforcement.

Experimental evaluation of a hydrogel composite desiccant wheel for dehumidification with high water uptake and low regeneration temperature

Rotary dehumidification, a key method for continuous solid adsorption dehumidification, is extensively utilised in various industrial and practical applications. The performance of the adsorbent within the desiccant wheel is a major determinant of its energy efficiency in practical applications. While studies on Metal Organic Frameworks (MOFs) and polymer desiccant wheels exist, the majority of rotary dehumidification systems continue to employ traditional adsorbents like silica gel and zeolite, which are plagued by low dehumidification capacity and high energy consumption issues. Super hygroscopic hydrogel, enhanced with a hygroscopic agent, has gained prominence in air treatment because of its outstanding hygroscopicity and low regeneration temperature. With the goal of integrating advanced materials into practical engineering applications and mitigating the heat and mass transfer loss and adsorption/desorption performance degradation due to volume expansion and viscous agglomeration post-water uptake in large-scale super hygroscopic hydrogel applications, this study successfully developed a hydrogel wheel, measuring 350 mm in diameter and 200 mm in thickness, using a honeycomb-shaped glass fibre paper substrate. Experimental findings demonstrate that the hydrogel desiccant wheel outperforms both the MOF and commercial low-temperature silica gel wheels under all tested environmental conditions. This advantage is particularly noticeable at 15 °C and 30 % Relative Humidity (RH), where the moisture content differential (Δd) in the hydrogel system is 2.96 g/kg, 1.89 times greater than the MOF system’s 1.56 g/kg and 5.19 times higher than the silica gel’s 0.57 g/kg. Furthermore, the controlled variable method was used to assess the impact of each operational parameter on the hydrogel wheel’s performance in both low and high moisture conditions, offering design insights for engineering applications.

Fiber Showdown: A Comparative Analysis of Glass vs. Polypropylene Fibers in Hot-Mix Asphalt Fracture Resistance

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.

Influence of Additives on Grinding Performance of Digital Light Processing-Printed Phenol Bond Grinding Wheels

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%).

Automatic characterization of capillary flow profile of liquid samples on μTADs based on capacitance measurement

Capillary flow profile of liquid samples in porous media is closely related to the important properties of liquid samples, including the viscosity and the surface energy. Therefore, capillary flow profile can be used as an index to differentiate liquid samples with different properties. Fast and automatic characterization of capillary flow profile of liquid samples is necessary. In this work, we develop a portable and economical capacitance acquisition system (CASY) to easily obtain the capillary flow profile of liquid samples on microfluidic thread-based analytical devices (μTADs) by measuring the capacitance during the capillary flow. At first, we validate the accuracy of this method by comparing with the traditional method by video analysis in obtaining the capillary flow profiles in μTADs of cotton threads or glass fiber threads. Then we use it to differentiate liquid samples with different viscosity (mixture of water and glycerol). In addition, capillary flow profile on μTADs with chemical valves (chitosan or sucrose) can also be obtained on this device. Lastly, we show the potential of this device in measurement of hematocrit (HCT) of whole blood samples. This device can be used to catalog liquid biological samples with different properties in point-of-care diagnostics in the near future.

Study of Compressive Strength of Glass Fiber Reinforced Concrete Cubes

Abstract: Nowadays, complex civil engineering work requires high-performance concrete materials. Researchers worked on reinforced concrete to provide sustainable solutions. Materials like carbon, glass, eggshell etc are used for reinforcement with concrete. While study of reinforced concrete cubes performance, compressive strength is an important parameter that need to be focused more. In this paper, experiments were carried out to study the influence of percentage glass fiber reinforcement in concrete on compressive strength. In order to evaluate Compressive Strength (N/mm2) obtained on CTM for GFRC cube of Size: 150x150x150 mm and the age of cube was kept 7 days, 14 days and 28 days. It was observed that maximum compressive strength can be achieved for glass fiber reinforcement of 10 % when age id cube is kept 28 days.

Investigation on mechanical properties and stealth characteristics of a novel gradient-stitched composite structure

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.

Mechanical and absorption properties of carbon-basalt and glass fiber reinforced composites: A comprehensive study with implications for advanced manufacturing technology

In this research, a combination of hybrid and non-hybrid composite materials were tested for their mechanical properties and water absorption rates. The study focused on composites produced through hand-layup techniques, examining their void percentage, morphology, and elemental composition. Specifically, three different stacking sequences of hybrid composites were compared with three non-hybrid composites of equal thickness. Combining carbon and glass allows the composites to balance flexural (367 MPa, 23 GPa) and tensile (440 MPa, 5.7 GPa) strength and modulus, all while remaining cost-effective and easily accessible. The glass fiber-based composites exhibited exceptional impact (27 J/cm2) strength due to their interfacial solid bonding. Additionally, the study found that basalt and carbon-basalt composites had varying degrees of water absorption when exposed to seawater and river water. SEM and EDS Mapping analyses were conducted to understand better fibrous and granular composites' mechanical properties and water absorption behaviors. These analyses provided valuable insights and a comprehensive knowledge of composite properties. Ultimately, the study recommends using hybrid composite materials for specific applications based on desired flexural tensile strength, impact strength, or water absorption characteristics.

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

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

Manufacturing of hexagonal cross-section thermoplastic matrix composite parts with automatic filament winding system

Thermoplastic filament winding is a flexible manufacturing method typically used in the production of cylindrical composite structures, allowing for in-situ consolidation without the need for a second consolidation step. The objective of this study is to produce non-cylindrical geometries, typically manufactured using thermoset matrix composites according to the literature, using the thermoplastic filament winding process. For this purpose, glass fiber (GF) reinforced polypropylene (PP) prepreg tapes were used to produce hexagonal cross-section thermoplastic composite parts. The critical process parameters; hot-air heater nozzle temperature, compression roller pressure, the linear speed of mandrel rotation, and corner radius of the mandrel, were determined using the Taguchi experimental design method. The interlaminar shear strength (ILSS) and maximum compressive strength (σmax) values were obtained as 211 MPa and 49.40 MPa as maximum, respectively. ANOVA analysis showed that the corner radius had the most significant impact on ILSS, while mandrel rotation speed and temperature were critical for σmax.

Prolonging rechargeable aluminum batteries life with flexible ceramic separator

Rechargeable aluminum batteries (RABs) are attracting significant attention for their high theoretical capacity and abundant reserves. However, the poor mechanical performance of glass fiber (GF) separators and the formation of Al dendrite severely hinder the practical cycle life of these batteries. Herein, a flexible ceramic separator was developed with simple coating technique, effectively improving the cycling stability of RABs. Compared with the commercial GF separator, this flexible ceramic separator has less thickness and superior electrolyte wettability, resulting in improved interfacial compatibility and minimized interfacial resistance. Moreover, its exceptional flexibility and toughness (stress of 39.34 MPa) coupled with uniform nanopore structure, which can effectively resist the penetration of dendrites. As expected, this ceramic flexible separator facilitates stable cycling of the symmetric battery for over 1762 h at 2 mA/cm2 and 2 mAh/cm2. It also permits the pouch Al//flake graphite full battery to achieve a coulombic efficiency of up to 90% even after 115 cycles. Apparently, this work developed the simple separator manufacturing strategy that provides an effective method to improve the cycling stability of RABs and extends the application to other types of batteries.