Glass Fiber Roving Research Articles

Four-dimensional printing of continuous glass fiber-reinforced thermoplastics

Shape memory polymers (SMPs) are a new class of materials in which their shapes can be changed over time. Despite their lightness and ease of fabrication, SMPs have very low recovery forces and are therefore inefficient when high loads are applied. To improve the mechanical properties of polymeric materials, glass fiber (GF) is commonly used as a reinforcement. The purpose of this study was to demonstrate a four-dimensional (4D) printing process using material extrusion additive manufacturing on both polylactic acid (PLA) and thermoplastic polyurethane (TPU). The goal was to improve the recovery forces in SMPs. GF roving was fed continuously into the nozzle of a three-dimensional (3D) printer to fabricate composite specimens. Also, multi-layer PLA/TPU specimens were printed. There was a measurement of shape fixity, shape recovery, and force recovery ratios. A multi-objective function analysis was performed to determine the optimum material based on recovery force priority in this study. In terms of recovery force, GF showed a superior effect. For composite specimens, shape fixity and recovery ratios decreased and increased, respectively. According to the result of optimization, PLA with 6.62 % GF proved to be the best material. PLA's recovery force has been improved by annealing heat treatment. Furthermore, cyclic experiments up to three cycles were conducted to evaluate the performance of the optimum material.

The Effect of Glass Fiber Storage Time on the Mechanical Response of Polymer Composite.

The growing demand for polymer composites and their widespread use is inevitably accompanied by the need to know their degradation behavior over a sufficiently long period of time. This study focuses on commercial glass fiber rovings, which were stored in the indoor environment for up to 11 years. Fibers with different storage times, from fresh up to the oldest, were used to produce unidirectional fiber-reinforced polyester composites that were characterized to determine their shear and flexural properties dependent on fiber storage time. A significant decrease in shear strength was observed throughout the aging of the fibers, down to a decrease of 33% for the oldest fibers. An important finding, however, was that the significant decrease in shear strength was only partially reflected in the flexural strength, which corresponded to a decrease of 18% for the oldest fibers at consistent flexural modulus.

Damage monitoring of pultruded GFRP composites using wavelet transform of vibration signals

A statistical procedure is presented for monitoring the damage of pultruded specimens using vibration data. Pultruded composite samples are processed by using continuous glass fiber rovings and epoxy matrix. Two different types of damages, a notch in the top layer and a hole at the midsection has been introduced individually in these samples. Vibration signals from healthy and damaged samples are processed using wavelet transform. various time–frequency domain statistical features have been extracted. Also, the time-domain features have been computed from the raw amplitude data. Further, both these features have been exploited to construct the feature space and significant features have been identified by evaluating the contribution rates. Finally, significant feature set is channeled as input to various machine-learning classifiers (deep neural network and support vector machine) and different classification accuracies have been estimated. The capability of these methods to early detect the damage in pultruded composites has been discussed.

하이브리드 강화재 적용을 통한 FRP 선박 V 스카프 접합 보수면의 기계적 특성

This paper aims to identify the mechanical properties of the hull plate of fiber reinforced plastics, which occupies 95.5% of the registered domestic fishing vessels for strength improvement after a repair by changing reinforced materials. Under the present legislations, in case of repairing the hull plate of fiber reinforced plastics, localized repair using only V- and X-scarf methods are acknowledged. The existing glass fiber reinforced material was replaced with the hybrid laminated method of carbon and aramid fiber before being applied to repair surface of scarf-processed parent material and by comparing the strength with the existing glass fiber mat and roving combination. The use effect when repairing the hull made of hybrid fiber rather than glass fiber was found. As a result of the repaired hull plate, the hybrid joint type exhibited an overall reduction in tensile joint efficiency rather than the existing resin and glass fiber roving and mat combination. However, in flexural joint efficiency improved in specimen applying aramid fiber hybrid compared to the existing joint method improved by up to 77.4%. A 1:12 scarf joint had a high effect in flexural strength rather than tensile strength. When carbon-aramid fiber was used partially appropriately by replacing the existing glass fiber, joint efficiency improved.

Orientation and Type of Non-dental Glass Fiber Towards The Flexural of Fiber Reinforced Composite

Introduction : Non-dental glass fiber can used as alternative dental glass fiber. Flexural strength to withstand masticatory loads that influenced by various factors, including the orientation and type of fiber used. Purpose : The purpose of this study was to see the effect of orientation and type of non-dental glass fiber on flexural strength. Method : The research method used FRC samples measuring 65 x 10 x 2,5 mm which were reinforced with non-dental glass fiber mats, roving, woven roving, and dental glass fiber roving. Non-dental glass fiber mats and woven roving was cut according to the length and width of the sample, while the non-dental glass fiber roving was weighed according to the weigh tof 4 sheets of dental glass fiber roving to meet the sample mold zone. Result : Glass fiber placed in the tension position in the sample mold. The flexural strength was tested using universal testing machine. This study indicate that the type of glass fiber doesn’t have a significant effect on the flexural strength of FRC with reinforced non dental glass fiber and dental glass fiber. Conclusion : The orientation of non-dental glass fiber roving as reinforcement of FRC has greater flexural strength than non-dental glass fiber with mats and woven roving orientation.

Enhancement of mechanical behavior of resin matrices and fiber reinforced polymer composites by incorporation of multi-wall carbon nanotubes

Herein, to enhance the toughness of resins and tensile strength of fiber-reinforced polymers (FRPs), multi-wall carbon nanotubes (MWCNTs) were incorporated as a toughening material into resin matrices. The effects of the MWCNT addition on the fracture toughness (KIC) and mechanical properties of epoxy and vinyl ester resins, and the tensile strength (σr) and stiffness of impregnated basalt, carbon, and glass fiber rovings were systematically examined. The enhancement mechanism was studied by scanning electron microscopy (SEM). The enhancement in the tensile strength of the FRPs was predicted. The results showed that as compared to pure epoxy resin, the 0.3 wt% MWCNT-modified epoxy resin exhibited elevated KIC, tensile strength (σt), flexural strength (σf), and impact strength (αcU). Similar improvements were discovered for the MWCNT-modified vinyl ester resins. Concentrated tortuous textures due to the bonding and bridging effects of MWCNTs were observed on the fracture surface by SEM. The σr of the basalt, carbon, and glass rovings obviously increased with the addition of MWCNTs, owing to the combined action of restricted crack propagation and the promoted co-stress of fibers. Additionally, the σr of MWCNT-modified basalt and carbon rovings exhibited a lower dispersion, resulting in a higher guaranteed strength. The modification method proposed above can effectively improve the mechanical properties and design strength of FRP.

Assessment of Long Fiber Spray-up Molding of Chopped Glass Fiber Reinforced Polydicyclopentadiene Composites

Chopped strands of glass fiber reinforced polymerized dicyclopentadiene (p-DCPD) was manufactured and mechanical properties were assessed. For the purpose, a lab-scale long fiber spray-up molding apparatus had been designed and built. Polydicyclopentadiene (p-DCPD) is a crosslinking polymer with a very rigid network structure resulting excellent mechanical and corrosion resistant properties. In this research, the length of the glass fiber roving was cut such that it would be 100 times its critical length. Uniformity of the fiber volume distribution was examined by varying the spray height, glass fiber weight percentage and the fiber length. Mechanical properties were measured for each processing conditions. It was found that tensile strengths of the specimen fabricated with 50 mm glass fiber were higher over the shorter (25 mm) fiber only if sufficient spray height was achieved. It is definitely desirable to use long strands of chopped glass fibers for composite fabrication processes however; a careful manufacturing precaution is required since the effect of the adhesion force between long fibers from the fiber entanglement cannot be ignored.

Combined Effect of Layers Number and the Glass Fiber Type on the Shear Strength Characteristics of Chlef sandy soil

The present study is dedicated to investigate the effects of the layers’ number and the type of fiber on the shear strength characteristics of Chlef silty sand. A series of 30 direct shear tests, by considering the number of layers and the types of glass fiber, subjected to three normal stresses 100, 200 and 300 kPa for loose and medium densities is presented. The test results showed that the presence of glass fibers contributed toward achieving a clear improvement on the shear strength of testing sand, with increasing normal stress, relative density and number of layers of both types of glass fibers. For all the performed tests, the optimum shear resistances were obtained with the medium dense sand reinforced with two layers of woven roving glass fiber type. In the point of view of the intrinsic characteristics of the composites, the inclusion of the glass fiber layers shows an increase in the cohesion intercept and the friction angle of the Chlef sand for both loose and medium dense sand states.

A Scale-up of Energy-Cycle Analysis on Processing Non-Woven Flax/PLA Tape and Triaxial Glass Fibre Fabric for Composites

In the drive towards a sustainable bio-economy, a growing interest exists in the development of composite materials using renewable natural resources. This paper explores the life cycle assessment of processing of Flax fibre reinforced polylactic acid (PLA), with a comparison of glass fibre triaxial fabric in the production process. The use of hydrocarbon fossil resources and synthetic fibres, such as glass and carbon, have caused severe environmental impacts in their entire life cycles. Whereas, Flax/PLA is one of the cornerstones for the sustainable economic growth of natural fibre composites. In this study, the manufacturing processes for the production of Flax/PLA tape and triaxial glass fibre were evaluated through a gate-to-gate life cycle assessment (LCA). The assessment was based on an input-output model to estimate energy demand and environmental impacts. The quality of the natural hybrid composite produced and cost-effectiveness of their LCA was dependent on their roving processing speeds and temperature applied to both the Flax/PLA tape and triaxial glass fabrics during processing. The optimum processing condition was found to be at a maximum of 4 m/min at a constant temperature of 170 °C. In contrast, the optimum for normal triaxial glass fibre production was at a slower speed of 1 m/min using a roving glass fibre laminating machine. The results showed that when the Flax and PLA were combined to produce new composite material in the form of a flax/PLA tape, energy consumption was 0.25 MJ/kg, which is lower than the 0.8 MJ/kg used for glass fibre fabric process. Flax/PLA tape and glass fibre fabric composites have a carbon footprint equivalent to 0.036 kg CO2 and 0.11 kg CO2, respectively, under the same manufacturing conditions. These are within the technical requirements in the composites industry. The manufacturing process adopted to transform Flax/PLA into a similar tape composite was considerably quicker than that of woven glass fibre fabric for composite tape. This work elucidated the relationship of the energy consumptions of the two materials processes by using a standard LCA analytical methodology. The outcomes supported an alternative option for replacement of some conventional composite materials for the automotive industry. Most importantly, the natural fibre composite production is shown to result in an economic benefit and reduced environmental impact.

Characterization and dynamic mechanical analysis of woven roven glass fiber/cerium-zirconium oxide epoxy nanocomposite materials

Fibre-reinforced composites have found wide applications in many structural and engineering products in recent decades. In the present study, we have prepared a hybrid epoxy nano composite reinforced with woven roving glass fibre and cerium (IV)-zirconium (IV) oxide nanoparticles. The hand-lay method was employed for sample preparation. This fibre and nanoparticle reinforced polymer composite was studied for its mechanical and viscoelastic behaviour. These properties were studied at nanoparticle contents of 0.5, 1, and 1.5 wt%. Structural and morphological characterization was explored using x-ray Diffraction and Field emission scanning electron microscope. Mechanical strength analysis revealed increases in the tensile, flexural, and impact strength to the extent of 16.8%, 7.8%, and 13%, respectively. This increase is in accordance with the incorporation of nanoparticles. The storage modulus also improved with an increase in nano cerium(IV)-zirconium(IV) oxide content. These nano composites find applications in industries such as shipbuilding and aircraft panel manufacture under conditions such as elevated temperatures, corrosion, or heavy loads.

Impact response of sandwich panels with polyurethane and polystyrene core and composite facesheets

An experimental study on the impact response of foam core sandwich panels subjected to low velocity impact is performed. Panels with glass fiber laminated facesheets and polystyrene and polyurethane foam core with density of 32 kg/m3, respectively 100 kg/m3, were tested in impact on an INSTRON Ceast 9340 drop tower at different impact energies. The composite facesheets were made of epoxy resin, glass fiber roving of 500 g/m2 and short glass fibers of 3 mm in 5 different combinations. The effect of foam core and facesheet type on the resulting impact damage and contact force is analyzed. It was noted that higher impact energies introduce matrix damages and the partial fracture of the fibers which significantly change the force-displacement histories, particularly after the maximum impact force is reached. Also, the use of polyurethane foam core increased the impact damage indentation in size and depth compared to the panels with polystyrene core. Panels having facesheets only with short glass fibers show a very poor resistance compared to the ones with roving and are completely perforated even for the smallest impact energy.

Paper twines in the pultrusion process – Pilot production and flexural characterization of sandwich rods

This paper describes the possibility of the use of paper twines as core reinforcement in thermoset pultruded sandwich composites. Paper twines and glass fiber rovings were co-impregnated with polyester resin and co-pultruded to form sandwich rods. Pultruded sandwich rods were up to 26% lighter with regard to typical monolithic glass fiber reinforced polyester rods. The specific flexural strength and Young's modulus of the sandwich rods were up to 25% higher than those of monolithic glass fiber/polyester commercial rods. Thanks to its light weight and its availability as a continuous twine, paper twines may be used with great flexibility in pultrusion of sandwich structures. This may lead to up to 20–30% weight reduction and cost saving without losing flexural performance.

Graphene-based surface heater for de-icing applications.

Graphene-based de-icing composites are of great interest due to incredible thermal, electrical and mechanical properties of graphene. Moreover, current technologies possess a number of challenges such as expensive, high power consumption, limited life time and adding extra weight to the composites. Here, we report a scalable process of making highly conductive graphene-based glass fibre rovings for de-icing applications. We also use a scalable process of making graphene-based conductive ink by microfluidic exfoliation technique. The glass fibre roving is then coated with graphene-based conductive inks using a dip-dry-cure technique which could potentially be scaled up into an industrial manufacturing unit. The graphene-coated glass roving demonstrates lower electrical resistances (∼1.7 Ω cm−1) and can heat up rapidly to a required temperature. We integrate these graphene-coated glass rovings into a vacuum-infused epoxy–glass fabric composite and also demonstrate the potential use of as prepared graphene-based composites for de-icing applications.

Performance of composite local glass fibre sheets and epoxy on flexural strengthening of reinforced concrete beams

Application of fibre sheets to strengthening reinforced concrete members has been investigated extensively. This paper presents the results on the use of composite local materials such as woven roving glass fibre sheets and epoxy to flexural strengthening of reinforced concrete beams. As many as 24 specimens with variation on the number of fibre layers (one and two layers) and end anchorage techniques (fasteners, U-shape straps, steel bolts) have been tested. It is shown that the effectiveness of glass fibre can be attained only on the specimens with one-layer sheet indicated by the rupture of fibre composite before specimen failure. Strengthening using two layers, bonding failure and delamination of fibre occur before the fibre develops maximum strength. Applying end anchors on the cut-off point of the two layers of fibreglass improves performance of the composite materials in the range of 5.0% to 16.5%. In addition, the end anchors also prevent delamination of the fibre sheet to occur at the cut-off point.

Effect of the volume fraction and curing time on thermal conductivity properties for some fibrous hybrid composites

In this research a hand –lay up method was employed to prepare hybrid composites from epoxy resin rein forced with woven roving glass fiber at different volume fraction (20%,30%,40%).Thermal conductivity was measured at the above volume fractions and curing time (2h),(4h).Experimental results showed that ,the thermal conductivity values increase with increasing the volume fraction and curing time.

Evaluation of Thrust force in Drilling Woven roving Glass fibre reinforced Aluminium Sandwich laminates with TiAlN coated drill using Taguchi analysis

TiAlN is a high-performance coating which outshines in coarse and hard-to-machine materials like cast iron, aluminium alloys, tool steels, and nickel alloys. This paper presents the prediction and evaluation of thrust force and Torque in drilling of Woven roving Glass Fibre Reinforced Plastic and Aluminium sandwich laminate. The Prediction is based on Taguchi method. The experimental results specify that the feed rate and the drill diameter are the most significant factors affecting the thrust force, while the feed rate and spindle speed contribute the most to the surface roughness. In this study, the objective was to establish a correlation between the feed rate, spindle speed and drill diameter with the induced thrust force and Torque in drilling sandwich laminate.

Nanocoating on alkali-resistant glass fibers by octadecyltrichlorosilane to improve the mechanical strength of fibers and fibers/epoxy composites

Surface defects cause the measured tensile strength of alkali glass fibers to be significantly lower than their theoretical values. Coatings can be used to “heal” surface flaws and to modify surface properties. In the present work, the nanocoating on alkali-resistant glass (ARG) fiber rovings was carried out by self-assembled monolayers (SAMs) of octadecyltrichlorosilane (OTS). The ARG roving was dipped into OTS nanosol, which deposited the organic–inorganic SAMs of OTS on the ARG surface. The assessment of changes in the fiber surfaces was characterized by scanning electron microscopy (SEM) and fluorescence microscopy, while the chemical changes were characterized by X-ray photoelectron spectroscopy (XPS). Furthermore, the influence of nanocoating on the tensile properties of ARG and OTS-treated ARG with and without an epoxy matrix was also studied. The SEM analysis revealed the formation of nanoscale layers on the ARG surfaces and the XPS confirmed the deposition of organic–inorganic monolayers. The tensile strength of ARG rovings with and without the epoxy matrix was improved significantly. The OTS treatment almost created a superhydrophobic nanocoating on ARG, which was confirmed by the sessile drop water contact angle, and the water absorption by the ARG/epoxy composites reduced.

Adhesive binders for layered alumopolymer composite materials

Results of studies of rheological and physico-mechanical properties of adhesive binders as components of adhesive prepregs based on glass fillers are presented. It was shown that VSK-14mR adhesive binder, which has low dynamic viscosity and high deformation and thermal strength characteristics, provides adhesive prepregs based on glass fiber rovings for layered alumopolymer composite materials.

Effects of elevated temperatures on the mechanical properties of basalt fibers and BFRP plates

In this article, the effects of elevated temperature on the mechanical properties of basalt fiber roving and pultruded basalt fiber-reinforced polymer (BFRP) plates were studied. For comparison, E-glass fiber roving and pultruded glass fiber-reinforced (GFRP) plates were also tested under the same conditions. It was observed that as the temperatures increasing from room temperature to 200°C, the tensile strength and elastic modulus were reduced by 37.5% and 31% for BFRPs, and reduced by 8.3% and 9.7% for basalt fiber roving, respectively. The deteriorated bonding strength between the basalt fiber and epoxy resin matrix at elevated temperatures is ascribed to the pronounced degradation of the BFRPs. After exposure to 120°C and 200°C for 4h, negligible degradation on mechanical properties occurred in BFRP plates, while a reduction in the Weibull shape parameter (m) is found for the basalt fiber roving. Compared to the glass fiber rovings and pultruded GFRP plates, the basalt fiber roving and BFRP plates showed much better mechanical tensile properties and temperature resistance.

Fiber dispersion and breakage in deep screw channel during processing of long fiber-reinforced polypropylene

Long glass fiber-reinforced thermoplastics are usually processed by pultruded granules, but glass fiber rovings were used to process long glass fiber-reinforced thermoplastics in this study. This article investigated the dispersion and breakage of fibers during extrusion processing of long glass fiber-reinforced polypropylene containing 30 wt% glass fibers at a certain processing conditions. For this study, the morphology of the surface and polished cross-section of helices was observed by digital photography, as was the morphology of the remaining fiber after burning. On this basis, the fiber/polymer system behavior in the screw channel and the dispersion mechanism of the fiber bundles were analyzed. Moreover, scanning electron microscopy (SEM) was used to observe individual fiber cross-sections to analyze the mechanism of fiber breakage. Finally, the effect of processing conditions such as temperature, screw speed and fiber content on fiber length and dispersion was studied. The results show that the fiber agglomerates composed of fiber bundles form near the barrel surface at the fiber feed point and then undergo three main stages: compression, impregnation, and dispersion. The fiber bundles separate into daughter bundles and individual fibers in different parts of the screw channel. In addition, the results indicate that the fibers can suffer tensile fracture and bending fracture during the extrusion processing. Finally, this paper includes suggestions for improving fiber bundle dispersion and reducing fiber breakage.