Glass Fiber Layers Research Articles

An Economic Approach to the Confinement of Different Concrete Classes with Carbon and Glass Fibers Reinforced Polymers

One of the current approaches for concrete retrofitting is called fiber reinforced polymer (FRP) wrapping. In this study, concrete retrofitting means compressive strength and seismic parameters improvement (such as failure strain, energy absorption, and ductility). Cost analysis may raise issues of concern regarding the economic value of this kind of retrofitting and for this reason, economic analysis was conducted based on experimental works. In this regard, 21 samples were prepared for three compressive strengths of concrete (20, 35, and 50MPa) and warped with different layers of carbon and glass fiber reinforced polymers (0, 1, 3, and 5 layers). Samples were subjected to stress-strain tests and concrete properties were estimated. The results showed that carbon and glass fibers, respectively, are more effective in improving the compressive strength and seismic parameters of concrete. But, the economic analysis indicated that glass fiber is more cost-benefit than carbon fiber in improving the concrete properties, especially for one layer of FRP. The economic analysis was not able to specify the application of FRP for which concrete samples are more economical, and for this reason, statistical analysis was used to respond to this vague and achieve a comprehensive assessment. The analysis indicated that the use of FRP is more cost-benefit for lower concrete strength.

A Fully Polarimetric Radar System for Non-Destructive Testing of Fiber Glass Layers

A Fully Polarimetric Radar System for Non-Destructive Testing of Fiber Glass Layers

Interlaminar shifts of two-layer aggressive-resistant combined plates based on metal and fiberglass

In this work, the stress and deformation states of plates made of metal layers wrapped with composite materials in the inner or outer layers were studied. The main goal of this research is to create durable, long-lasting and aggressive environment-resistant structures that can easily bear external dynamic and static loads. The work used the Navier method to study the effects of interlayer displacement. It was found that the lower the modulus, the greater the effect of joint compliance on the deformation of laminated composite plates. A regularity has been established that the greater the thickness of the bearing fiberglass layer, the less the effect of the shear modulus of the seam on the stresses and deformability of two-layer combined slabs. A regularity has been established, the greater the thickness of the bearing metal layer, the less the effect of the shear modulus of the seam on the stresses and deformation of two-layer combined plates.

Experimental and numerical determination of interlayer shear strength of glass fiber-reinforced epoxy composites

This study aims to produce glass fiber composite plates by vacuum infusion method and to determine the interlaminar shear strength (ILSS) under the short beam test. For this purpose, composite plates were produced under the effect of vacuum and temperature by adding glass fiber layers on a flat vacuum table. Short beam tests were carried out on the obtained laminated composite plates and the interlayer shear strength, which is generally characterized by delamination damage, was investigated. In the numerical part, the tests were modeled using the LS-DYNA finite element package program, and the Hashin damage criterion-based material model was used to see the damages that occurred in the composite structure after the tests.

Quasi‐static fracture characterization of fiber metal laminate with crack resistance curve based on δ5

AbstractFiber metal laminate (FML) is a hybrid composite typical in aircraft industry. It is necessary to effectively characterize the quasi‐static fracture performance of FML, considering the importance of damage tolerance design of aircraft structures and the complicated fracture mechanism of FML. In present investigation, glass fiber reinforced aluminum laminates (Glare) with middle cracks were tested under quasi‐static tensile load. The experimental crack resistance curve (R curve) based on the special crack opening displacement at original crack tip (δ5) was used for revealing the superior crack resistance of Glare laminate to aluminum sheet, which expressed in crack extension aspect was the extended critical crack length. This was thought to be benefit from the contributions of glass fiber layers and fiber/metal delamination, by performing the progressive damage analysis. Since δ5 can embody the elastic–plastic response of the crack but without need to interactively correct for crack tip plasticity. The δ5‐R curve‐based macro and meso fracture models were proposed to accurately predict the residual strength and stable crack extension of Glare laminate, which gave further evidence for the effectiveness of δ5‐R curve in characterizing the quasi‐static fracture performance of FML.

Enhancement the Crashworthiness Parameters Using Natural and Hybrid Composites under Axial Static Crushing

In automotive applications, replacing heavy and expensive materials with light and cheap natural fiber leads to noise reduction, strength enhancement and fuel management. Enhancing the absorption of energy, controlling the failure style of composite thin shell tube and utilizing it instead of thin-walled steel columns in vehicle structural parts can provide more protection for occupants during collisions. This research investigates the possibility of gradually replacing metallic materials with natural and hybrid fibers in industries. The hand layup technique is utilized to study the performance of fiber reinforced epoxy composite tubes under static crushing to examine the jute fiber effect with different fibers types on the failure mechanism. The research studies the effect of using different fibers types on stress and strain after determining the tubes load-displacement curves. Total of 48 specimens are fabricated at room temperature and tested with a constant speed 1.5 mm/sec using one resin (epoxy) type and three fibers types (Glass, Kevlar, Jute). Two circular and square geometries with three heights (200 mm,250 mm,300 mm) including two circular diameters and two square side lengths are used to investigate the crashworthiness parameters. The Kevlar and glass fiber tubes showed low and unstable behavior. Replacing two layers of Kevlar or Glass fiber by two layers of natural jute fiber enhanced the crash worthiness parameters particularly, failure type. The hybrid jute with Kevlar accomplished desirable and best results followed by hybrid jute with glass.

Thermal and constructional behavior of light concrete block using many crushed materials as aggregate with economic analysis

The riverine aggregate have high mass density (2700Kg/m3) and thermal conductivity (2.8W/m.c0) this reflects the properties of the block concrete in order to decrease these properties , the riverine aggregate must be replaced by any materials have low density and thermal conductivity such as : scrap brick , lime stone , or black stone (pumice). In this paper, block concrete samples (solid and hollow), with dimensions of (200x200x200mm) , were constructed mixing ratio of (4:2:1)by mass and water percentage of 0.5 were used . The thermal and constructional behavior of these blacks was investigated at Baghdad climate zone during one year at 21th day of each month for 15 hr/day. The test results showed that, using pumice racks as aggregate reduced the density by about 44% and increased the energy saving by about 34%. However, this enhancing in the properties was accompanied with reduction in the tensile and compression stresses of unloaded walls. Using limestone as aggregate gave 20% reduction in density with 5% increase in the energy saving 60% reduction in density and 40% increase in the energy saving were achieved when using gypsum block with fiber glass layers.

Research on Delamination Failure of Insulator in Electromagnetic Rail Launcher

The electromagnetic rail launcher (EMRL) G10 insulator is prone to delamination failure during launch, which affects the life of EMRL. In order to explore the reasons for the delamination failure of the insulator, the EMRL eddy current field calculation model is constructed firstly, and then the transient electromagnetic (EM) force distributions of the armature and the rail are calculated and verified by the combination of finite element and experiment. Finally, the EM force is used as the input, and combined with bolt pretightening force, friction force, and impact force, the multitype mechanical coupling solution is carried out. The simulation indicates that stress concentration occurs at the inner chamfer of the insulator end. The interlaminar shear stress exceeding the ultimate strength of the material and the fatigue damage caused by stress cyclic loading are the main reasons for the delamination failure of the insulator. The delamination crack is parallel to the direction of the glass fiber layer, and the interlaminar shear force peels off the upper fiber from the resin, forming a through-type delamination damage of the test prototype insulator. Optimizing the structure or material to improve the shear resistance of the insulator can prolong the life of the insulator.

Ansys-Based Evaluation of Natural Fiber and Hybrid Fiber-Reinforced Composites

In this research, we analyzed natural composite structures that optimize the material and weight of the structure. Green composites are made of natural fibers and epoxy resin that are biodegradable, recyclable, and eco-friendly. Core material failures include wrinkling, failure in compression, and buckling. To address these issues, this work attempted to create CAD models using jute fiber, glass fiber, and epoxy resin with various ply sequences using angle orientations of 0°, 30°, and 45°, and 2–4 mm thick laminates were produced. After creating CAD models, the material strength, stiffness, deformation of samples, shear strength, strain, and other mechanical properties of the natural-fiber-reinforced composite laminates were analyzed. The samples were based on two layers of glass fiber as a core with natural fiber plies below and above this core. The natural fiber with epoxy resin, the hybrid composite with jute fiber, and the glass fiber with epoxy resin were prepared and mechanical properties of the samples were evaluated with Ansys. The results indicated that the 0° ply orientation of 3 mm thickness had a low deformation (0.237 mm) and was the best material. The tensile test was performed for natural-fiber-reinforced composite and hybrid natural reinforced composite laminates at various thicknesses and at various ply orientations using a tensile load of 2500 N. In this investigation, the best material was the one with the thickness of 3 mm with the Young modulus 35.59 GPa at 0.149 strain with 5303 Pa stress conditions. Further, the above conditions were noted with low deformation (0.237 mm) at 0° ply orientation and tensile strength was noted as 1188 GPa at 3 mm with 45° ply orientation. This hybrid composite material can be considered for unmanned aerial vehicle applications.

Fabrication and characterisation of GFRP composite as skin material of sandwich structure

Sandwich structures are being widely used in many engineering applications because of their high strength, stiffness, and stiffness-to-weight ratio. This work focuses on fabrication and characterisation of glass fibre composite which can be used as skins material of sandwich structure for engineering applications. To fabricate the Glass Fibre Reinforces Polymer (GFRP) composite, the glass fibres, epoxy LY 556 and binder AR 953 are considered. The epoxy and binder is mixed with a proportion of 1:10. The composite with different thicknesses are prepared by considering number of glass fibre layers and epoxy matrix. The hand Layup process is used to fabricate the GFRP composite. The microstructure of the GFRP composite is extracted by X – Ray Diffraction test on various samples. Various tests have been conducted to investigate the mechanical properties of the Glass Fibre Reinforced Polymer (GFRP) composite. From the experiments it has been observed that the composite has good mechanical properties. The results show that the composite can be used as the skin of the sandwich structure with high strength and stiffness-to-weight ratio.

Machining GLARE fibre metal laminates: a comparative study on drilling effect between conventional and ultrasonic-assisted drilling

GLARE laminates are multi-layered metal-composite materials created from bonding sheets of metallic alloys with carbon or glass fibre layers. The application of hybrid-conventional machining processes such as ultrasonic-assisted drilling (UAD) is becoming of great interest to the aerospace industry due to its capability in reducing the cutting forces and tool wear which are directly responsible for drilling-induced delamination. There is rich literature on the conventional drilling (CD) of GLARE, but no work reported using UAD process. This study will fill this gap and investigate the UAD of GLARE laminates using an indigenously developed UAD system. The influence of spindle speed and feed rate on thrust force and surface roughness metrics (Ra and Rz) were investigated under CD and UAD regimes. The quality of the borehole and damage mechanisms in the laminate constituents was examined using scanning electron microscopy (SEM). The contribution of the drilling parameters on the measured outputs was further evaluated using the analysis of variance (ANOVA) statistical analysis. It was found that UAD resulted in a significant reduction in thrust force by up to 65% while surface roughness metrics Ra and Rz were unaffected by the type of drilling process used. SEM analysis showed irregular and fuzzier surfaces in glass fibre layers in holes machined using UAD due to the longitudinal vibration of the tool.

Using Response Surface for Searching the Nearly Optimal Parameters Combination of the Foam Concrete Muffler.

A car muffler is a device to improve car noise emission. Some conventional mufflers use layers of glass fiber as a material to absorb noise. However, filling glass fiber is an environmentally unfriendly work, mainly manually filling with chop strand fiber. This research selected a composite material of glass fiber and foam concrete to replace chop strand fiber to avoid this hazard and maintain the muffler's good noise reduction performance. A response surface methodology with a two-way factorial experimental design repeated the center point twice is performed. The density of the foamed concrete and the weight of the glass fiber is being considered in order to determine the nearly optimal combination of the values in two factors. The response variable is the loudness sensation in Sone of the noise generated from the muffler. At present, the lowest loudness sensation from the two-way factorial design is 16.6494 Sones, which occurred for a muffler with a formula combination of a density of 0.2 g/cm3 and 40 g of glass fiber. The significance of this paper is the presentation of a new application of foam concrete to the green muffler design. To the best of our knowledge, this unique area has never been tackled in the material application of concrete. We have discovered that foam concrete indeed does an excellent job in terms of noise reduction as compared with that of a market muffler.

An Experimental Study of Static and Dynamic Behavior of the Hybrid Composite

ABSTRACT Hybrid composites containing natural fibers are widely used for various applications due to their superior mechanical properties over synthetic fibers. The mechanical behavior of such hybrid composites under dynamic loading is a key concern. In the present study, a six-layered hybrid composite fabricated with four different layers of natural (sisal, flax, jute, and hemp) fibers, with top and bottom layers of synthetic glass fiber, is investigated for the impact strength and strain rate effects. The fractography at different strain rates has been analyzed using scanning electron microscopy. From the investigation, it is found that the strength bearing capacity of the hybrid composite increases as the strain rate is increased from 0.00022 s−1 to 0.0888 s−1. It is observed that there is an enhancement of 8.21% in the tensile strength, with average hardness and impact energy, which are 48.5 HV and 8 J, respectively. It is concluded that the developed composite is suitable for high strain rate applications.

Layer-structured hydrogen permeable membranes and their application in hydrogen membrane fuel cells

• Significantly improved hydrogen permeability at low temperature. • Negative activation energy for hydrogen permeation due to the V/Nb mid-layer. • Superior hydrogen permeability over the permeability of PdAg 25 at 298K. • Low-temperature operation of hydrogen membrane fuel cells. V and Nb are hydrogen permeable metals exhibiting greater hydrogen purification ability than Pd, but the permeability is not high enough due to low hydrogen dissociation and surface oxidation. In this study, two types of non-Pd hydrogen permeable membranes with a triple layer structure, Ni 64 Zr 36 /V/Ni 64 Zr 36 and Ni 64 Zr 36 /Nb/Ni 64 Zr 36 , have been prepared to produce a stable membrane exhibiting superior hydrogen permeability at low temperature range near to room temperature. The triple layer consists of 10 to 100 nm - thick amorphous Ni 64 Zr 36 thin films deposited by magnetron sputtering onto the surfaces of each 25 μm - thick crystalline V and Nb membranes. Significantly high hydrogen permeability over that of PdAg 25 below 373 K was observed in the prepared membranes. The performance of the triple membranes and the effect of the Ni 64 Zr 36 coating thickness on its hydrogen permeability are reported. Low-temperature hydrogen membrane fuel cells (LT-HMFCs) are built using the composite electrolytes composed of the suggested triple membrane and a glass fiber layer with phosphoric acid. The Nb and V interlayer plays an important role in implementing LT-HMFCs by improving hydrogen solubility and increasing hydrogen permeability at low temperature through its intrinsic activation energy, which is inversely proportional to temperature. The maximum output power obtained from LT-HMFC with 50 nm - thick V mid layer was 0.98 mW/cm 2 , at 423 K.

Investigation of the effect of steel fiber (200 mesh size) hybridization on properties of steel/glass fiber and steel/basalt fiber reinforced epoxy composite laminates

AbstractSteel fiber is the most common metal fiber used due to its cost‐effectiveness, high performance, and availability despite its heavyweight. This study is an attempt to evaluate the mechanical properties of steel/glass fiber and steel/basalt fiber‐reinforced epoxy composites. The symmetric hybrid laminates were produced by replacing the innermost 1, 2, 3, and 4 layers of steel fiber (200 mesh size) with basalt and glass fiber layers. The specimens were subjected to tensile, flexural, and Charpy impact tests in accordance with relevant ASTM standards. Moreover, fracture surfaces were analyzed, and the micrographs were obtained using a scanning electron microscope. The results showed that a high improvement in tensile strength was achieved with BS1–E (1 layer steel mesh–8 layers basalt) and GS1–E (1 layer steel mesh–8 layers glass) hybrid composites, with an increase of 528% and 233%, respectively, compared to steel fiber reinforced epoxy composites. Similarly, BS1–E and GS1–E hybrid composites showed the highest flexural strength increase of 82.2% and 66.8%, respectively, compared to steel fiber reinforced epoxy composites. Consequently, the potential to hybridize steel fiber with glass fiber and basalt fiber could create new materials with unique physical structures and synergistic effects on mechanical properties.

Multi-scale thermal, energetic and economic analysis of composite insulating materials made of silica aerogel in a fibrous inorganic mat

Composite materials made of silica aerogel in a fibrous inorganic mat, hereafter called “aerogel blankets”, represent promising insulating materials that can overcome the low mechanical resistance of monolithic aerogels, while preserving their very low thermal conductivity. Firstly, this paper details an experimentally validated mathematical model to predict the aerogel blankets’ effective thermal conductivity, as a function of the blankets' density, fiber volume fraction, and temperature. Secondly, an experimental test building retrofitted internally with a layer of needle glass fiber (NGF) aerogel blanket is monitored, and its thermal behavior is compared to the baseline case before the retrofit. The retrofitted wall U-value is derived from experimental data series using stationary and transient parametric methods. Then, a validated whole building Energy Plus numerical model is used to predict the annual energy consumption of a detached single-family house retrofitted with an NGF aerogel blanket, in the climates of Brussels (Belgium), Nice (France), and Stockholm (Sweden). Lastly, a 1-D COMSOL multiphysics model evaluates the economic profitability of installing the blanket as an interior thermal insulation system. Results show that the aerogel blankets have an effective thermal conductivity of about 0.0165 W.m−1.K−1. The designed mathematical model can reliably predict the gaseous conduction in the blanket, but deviations from the experimental measurements appear when considering the radiative and solid conduction components. The blanket's effective thermal conductivity increases with fiber volume fraction and temperature while its dependency curve to density is concave, with a minimum for densities of around 140 kg.m−3. Retrofitting a wall with 2.5 cm of NGF aerogel blanket as an internal insulation system almost doubles the thermal resistance of the experimental wall and decreases the heating load by more than 40 % in all tested climates. Internal thermal insulation with aerogel blankets is more profitable than conventional insulation materials, in places of high floor area price, because it can preserve the indoor living space.

Performance of polylactide biopolymer as matrix material for woven fiber composite laminates

The first purpose of this study was, as the first time in the literature, to investigate usability of polylactide (PLA) biopolymer as the matrix of high-performance composite laminated structures having woven forms of glass and carbon fibers. For this purpose, 2-14 layers of 2 × 2 twill Carbon Fiber (CF) and 1 × 1 plain weave Glass Fiber (GF) forms were stacked by PLA powders followed by consolidation of these layers by compression molding technique. After conducting various tests and analysis it was observed that significant improvements in the mechanical and thermal properties could be obtained by laminating PLA with woven CF and GF layers. For instance, mechanical properties obtained for PLA/CF laminates with 14 layers were flexural strength of 641 MPa, flexural modulus of 34 GPa and interlaminar shear strength of 38 MPa. Another purpose of this study was to compare mechanical performance of the PLA matrix laminates with Epoxy matrix laminates having exactly the same type and number of GF and CF layers. It was revealed that mechanical properties of the PLA/CF laminates were approaching to the values of the Epoxy/CF laminates (e.g. flexural strength of 607 and 673 MPa, respectively); while due to poor adhesion between the PLA matrix and Glass Fiber surfaces, the properties were lower in the PLA/GF laminates (e.g. flexural strength of 302 and 553 MPa, respectively). Therefore, it could be generally concluded that, in terms of mechanical performance; traditional thermoset Epoxy matrix could be replaced with the renewable biopolymer PLA matrix in the Woven Carbon Fiber laminates. For the Woven Glass Fiber laminates, a proper sizing treatment with a PLA compatible silane coupling agent would be necessary.

Ballistic studies on Kevlar - glass fibre hybrid laminated epoxy composites

In this present work, post ballistic studies on Kevlar – Glass Fibre laminated composite targets has been made. The targets made of Kevlar and Glass fibre with epoxy matrix were prepared by hand lay-up method. A total of seven laminated composites were fabricated by altering the number of Kevlar and glass fibre layers; and ballistic experiments were conducted by firing 9 × 19 mm parabellum projectiles on the targets. The Specific Energy Absorption (SEA) and the Back Face Signature (BFS) of the targets were calculated after the projectile impact. The results indicate BFS values of the laminate composite targets were below 44 mm as per the requirement of NIJ standard. The amount of kinetic energy required to completely penetrate the projectile into the glass fibre hybrid laminate composite was higher compare to pure Kevlar fibre laminates. Also, from the Scanning Electron Microscopy (SEM) analysis, the failure mechanisms of the Kevlar - Glass fibre composite targets were studied and discussed in detail.

Effect of the quartz powder on the performance of the two layers glass fiber reinforced polymer composite with emulsion binder

In the paper, effect of quartz additions on the durability of a polymer composite was investigated. The tested material was based on a resin MC-DUR 1200VK with two layers of E-type glass fiber reinforcement of an area density 300 g/m2 with an emulsion binder. The quartz was added in form of powder of fraction 0.1–0.3 mm in different proportions. Durability was measured in terms of specific wear work obtained from the novel tribological tester TT-4. Its important feature was the application of friction belt instead of disc or plate, which made it possible to avoid undesirable impact of the used friction surface and wear debris on the measurement results. Apart from that, standard measurements of flexural strength, shear strength between the layers, tensile strength, proof resilience, and microhardness were performed. It was found that the examined polymer composite increased its wear resistance when it contained 1% of the quartz powder. Similarly, the best results were achieved for the composite with 1% addition of quartz for the shear strength and proof resilience. However, further increase of the addition content caused decrease of the wear resistance. On the other hand, in comparison to the composite with no quartz powder, all other properties worsened after the quartz powder was added in any proportion. Despite no clear trends in characteristics after quartz addition was present, important finding was that it was disadvantageous to increase above 1% addition of quartz powder in the composite of resin MC-DUR 1200VK reinforced with two layers of E-type glass fiber of a weight 300 g/m2 with an emulsion binder. Initial researches also demonstrated that quartz additions might have different effect on the similar composite with other sort of reinforcement.

Investigation of the photoisomerization property of donor-acceptor Stenhouse adducts on ester-modified glass

The isomerization process of donor-acceptor Stenhouse adducts (DASAs) is closely related to its surrounded physicochemical environment, this work focuses on the promotion of ester-modified glass fiber to the isomerization process of DASAs compared with the untreated glass fiber. The ester-modified glass fiber is prepared through a two-stage method, the coating procedure is stepwise monitored through the scanning electron microscope(SEM) and the energy dispersive spectrometer(EDS). The ester functional groups on the outmost layer of glass fiber act as a catalyst, lowering the energy level of the intermediate state of DASAs and therefore promoting isomerization performance of DASAs where the time to reach cyclic dominant states shorten from 116 s to 82 s and the efficiency of cyclic-to-linear increased almost 6 folds.