Glass Fibre-reinforced Polyester Research Articles

Investigation of effects of environmental conditions on wear behaviors of glass fiber reinforced polyester composite materials

AbstractGlass 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.Highlights 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.

Mechanical behavior of glass fiber-reinforced polyester in a humid environment

Glass fiber composite materials have been well known in certain maritime applications for a long time, being used in several applications in different fields. The characteristics of Glass fiber-reinforced Polyester (GFRP) depend on the contained fibers, the matrix used, and the fiber-to-total volume ratio. GFRP is a polymer material used in various fields; it is generally preferred for its ease of installation and its very long lifespan, even in the presence of aggressive fluids. The aim of this research is to study the evolution of mechanical properties (tensile strength and flexural strength) of GFRP preserved in different environments such as open air (control), drinking water, and seawater (harsh environment). Additionally, tests on GFRP are conducted through chemical characterization studies or SEM observation of the resin. Lastly, GFRP is considered to be chemically stable for a conservation period of one year in seawater. Finally, despite the conservation of GFRP for a year in a humid and sulphate environment, we note that the connection between the fibers and the matrix is ​​in good condition, or the conservation environment has no influence on the GFRP composite.

Experimental study of the mechanical and optical properties of glass-polyester fiber composite based on response surface methodology

Due to the intricate amalgamation of various components, composite materials boast mechanical properties that surpass those of their constituents. Among these composite materials, glass fiber-reinforced polyester composites emerge as prominent contenders, finding extensive utility, especially in agricultural greenhouse construction. These structures garner significant acclaim for their exceptional ability to withstand adverse weather conditions, ensure prolonged durability, and transmit light efficiently, thus creating optimal growing conditions. Consequently, they have become the favored choice among farmers seeking dependable and sustainable environments for cultivation. Within the scope of this study, we employ Response Surface Methodology (RSM) as a comprehensive tool to delve deeply into the mechanical and optical characteristics inherent in such composite materials. Our investigation is meticulously tailored to unravel the intricate interplay among crucial factors such as fiber content, length, and plate thickness, elucidating their direct impacts on mechanical properties like stress and elasticity modulus. Our rigorous examination reveals that the pinnacle of mechanical performance is attained within a specific range: fiber content ranging from 20% to 40%, fiber lengths spanning 35 to 45 mm, and plate thicknesses measuring between 0.6 to 3 mm. Furthermore, our meticulous analysis of transmittance measurements uncovers an intriguing correlation: thinner thicknesses and lower fiber content correspond with heightened light transmission across the visible spectrum. Conversely, elevating the fiber content or thickness enhances mechanical robustness but concurrently diminishes light transmittance. Thus, achieving a harmonious equilibrium among these attributes becomes imperative for the pragmatic construction of agricultural greenhouses. Additionally, we venture into incorporating ultraviolet (UV) plastic films to augment the optical prowess of these composites, further elevating their efficacy in greenhouse applications. By embarking on this comprehensive investigation, our overarching objective is to propel sustainable farming practices forward by furnishing a nuanced understanding of the multifaceted factors that shape the performance of glass fiber-polyester composites in agricultural greenhouse applications.

Investigation of the Effects of Environmental Conditions on Wear Behaviors in Glass Fiber Reinforced Polyester Composite Materials Containing Different Types of Polyester and Low Profile Additive

Kompozit malzemeler, gelişen teknoloji ile birlikte günümüzde birçok alanda başarıyla kullanılmaktadırlar. Elyaf takviyeli polimer kompozitler, yüksek dayanım ve düşük maliyet özelliklerinden dolayı en sık tercih edilen kompozit malzemelerdir. Cam elyaf takviyeli polyester (CTP) kompozitler kullanım alanlarına göre istenilen mekanik ve tribolojik özellikleri karşılayan polimer matrisli ve cam elyaf takviye malzemeli bir kompozit türüdür. Cam elyaf takviyeli polyester kompozit malzemeler farklı türlerde polyester ve çekme katkıları içerebilmektedir. Çevresel koşullar cam elyaf takviyeli polyester kompozitlerin aşınma dayanımı üzerinde etkili olmaktadır. Bu çalışmada, iki farklı türde polyester (ortoftalik ve izoftalik) ve çekme katkısı (polistiren ve plastifiyen) içeren cam elyaf takviyeli polyester kompozit malzemelerin farklı çevresel koşullar (UV ışıma, asit ortamı, tuzlu su ortamı, hızlandırılmış yaşlandırma, hidrotermal yaşlandırma ve termal çevrim) altındaki aşınma davranışları incelenmiş ve farklı türlerde polyester ve çekme katkısı içeren numunelerde çevresel koşulların malzemelerin aşınma davranışları üzerine olan etkileri araştırılmıştır. CTP kompozit numunelerin aşınma dayanımına çevresel koşulların etkileri dikkate alındığında her iki numunede de UV ışıma ortamına ve hidrotermal yaşlandırmaya maruz kalan numunelerin aşınma dayanımının arttığı gözlemlenmiştir. CTP kompozit malzemelerin içerisinde polistiren çekme katkısının kullanılması malzemenin aşınma dayanımını iyileştirmektedir. Ortoftalik polyester reçine içeren CTP kompozit numunelerin, izoftalik reçine içeren numunelere kıyasla aşınma dayanımları daha iyidir.

Comparative Study of Commercial Glass Fiber-Reinforced Polyester Composite Beams: Thermal Behavior and Durability to QUV Exposure

Comparative Study of Commercial Glass Fiber-Reinforced Polyester Composite Beams: Thermal Behavior and Durability to QUV Exposure

Aluminum, an alternative to GRP for manufacturing of sports boats

Pollution is being discussed more and more in the world. It is known that the production of Glass Fiber Reinforced Polyester (GRP) is a polluting process. Also, the implementation of GRP is a process that can cause various ailments to the personnel who apply it. Over time, boats made of GRP suffer degradation due to interaction with the environment: cracks, exfoliation of the outer layer of gelcoat, etc. These degradations must be remedied, operations that involve the application of substances that are also polluting. More and more traditional manufacturers of sports boats are replacing GRP with aluminum. This, although the process of obtaining it from the ore is not without toxic components, is less polluting and friendlier to the executors than GRP. In this paper, we seek to elucidate the advantages that aluminum has over GRP in the construction of sports boats.

Experimental, numerical and analytical study on axial compression buckling of chopped glass fibre-reinforced polymer cylindrical shells

A series of experiments were carried out to investigate the buckling response of chopped strand mat glass fibre-reinforced polyester (CSM-GFRP) cylindrical shells when subjected to axial compression load. Finite element modelling by using ABAQUS was performed to verify the experimental results, then a parametric study was conducted to investigate the effect of wall thickness, shell height, radius, young’s modulus, fibre volume fraction, and geometric imperfections on the buckling load of the CSM-GFRP cylindrical shells. The findings revealed that the buckling load was decreased with increasing the radius-to-wall thickness ratio (r/t) and increasing the value of the imperfection amplitude-to-wall thickness ratio, Additionally the results indicated that the buckling load increased with increasing the fibre volume fraction. Finally, an equation was proposed to predict the buckling load of the CSM-GFRP cylindrical shells using nonlinear regression analysis.

Identification of regularities in the behavior of a glass fiber-reinforced polyester composite of the impact test based on ASTM D256 standard

In this research, commotional analysis based on the finite element analysis (FEA) has been performed to investigate IZOD impact test based on the ASTM D256 standard. The ANSYS model primarily employs a composite constructed of glass fiber-reinforced polyester for the boundary conditions. The CEAST 9050 instrument was used to implement the impacting technique in the experimental inquiry. By employing mathematics, we have calculated that the applied force is 9.2 N. A hammer traveling at a speed of 3.5 meters per second is used to strike the samples, and the results are recorded after each blow. The object of this study is the mechanical properties and structural integrity of the composite material composed of glass fibers and polyester when subjected to impact forces. The main hypothesis of the study encompasses the optimism that the glass fiber-reinforced polyester composite, when put through the Izod impact test in accordance with ASTM D256. Convergence between the overall deformation indicator and the numerical result has occurred. Results from the numerical analysis were examined and confirmed, and compared to those from the experiment. The specimens in this study were totally distorted at three different thicknesses (6 mm, 8 mm, and 10 mm). Deformation was found to be greatest for the thinnest value of thickness considered in the study (6 millimeters), as determined by the results of the computer analysis. This was the case even though the thickness value was not the sole criterion. This is the actual state of affairs. The specimen was subjected to a von-Mises stress at three different thicknesses of 6 mm, 8 mm, and 10 mm. The computer investigation revealed that the Von-Mises stress was highest at the thinnest possible thickness of just 6 millimeters. Internal energy, kinetic energy, and touch energy are only few of the various types of energy that have been studied in the context of energy conservation

The Reduction Factor of Pultrude Glass Fibre-Reinforced Polyester Composite Cross-Arm: A Comparative Study on Mathematical Modelling for Life-Span Prediction.

This paper presents an experimental and numerical investigation of pultruded composite glass fibre-reinforced polymer (pGFRP) cross-arms subjected to flexural creep behaviour to assess their performance and sustainability in composite cross-arm structure applications. The primary objective of this study was to investigate the failure creep behaviour of pGFRP cross-arms with different stacking sequences. Specifically, the study aimed to understand the variations in strain rate exhibited during different stages of the creep process. Therefore, this study emphasizes a simplified approach within the experiment, numerical analysis, and mathematical modelling of three different pGFRP composites to estimate the stiffness reduction factors that determine the prediction of failure. The findings show that Findley's power law and the Burger model projected very different strains and diverged noticeably outside the testing period. Findley's model estimated a minimal increase in total strain over 50 years, while the Burger model anticipated PS-1 and PS-2 composites would fail within about 11 and 33 years, respectively. The Burger model's forecasts might be more reasonable due to the harsh environment the cross-arms are expected to withstand. The endurance and long-term performance of composite materials used in overhead power transmission lines may be predicted mathematically, and this insight into material property factors can help with design and maintenance.

Investigation of mechanical properties of aluminum–glass fiber-reinforced polyester composite joints bonded with structural epoxy adhesives reinforced with silicon dioxide and graphene oxide particles

In this work, to investigate the mechanical properties of aluminum–glass fiber-reinforced polyester composite joints bonded with structural epoxy adhesives reinforced with silicon dioxide (SD) and graphene oxide (GO) particles, firstly, SD and GO particles were added to epoxy adhesive in varied weight percentages. After the surface treatment made by sanding aluminum and composite sheets with abrasive sandpaper, aluminum sheets and glass fiber-reinforced polyester composite sheets were bonded. Adhesives containing 0.2% SD and 0.25% GO had tensile strengths that were approximately 15.89% and 14.03% greater than neat epoxy, respectively. The lap shear strength of neat epoxy was improved with the addition of filler in all samples, and 0.2% SD and 0.25% GO-reinforced adhesives increased the shear strength of the neat epoxy by 66.57% and 125%, respectively. The adhesion, thin-layer cohesive and light-fiber tear were noted, as well as cohesive and fiber-tear failures based on the damaged surfaces of the samples.

Advanced Ultrasonic Inspection of Thick-Section Composite Structures for In-Field Asset Maintenance.

An investigation into the inspection capabilities of in-field advanced ultrasound detection for use on ultra-thick (20 to 100 mm) glass fibre-reinforced polyester composites is presented. Plates were manufactured using custom moulding techniques, such that delamination flaws were created at calibrated depths. The full matrix capture technique with an on-board total focussing method was used to detect flaws scanned by a 0.5 MHz linear array probe. Flaw through-thickness dimensions were altered to assess the threshold for crack face separation at which delaminations could be identified. Furthermore, part thickness and in-plane flaw dimensions were varied to identify the inspection capability limitations of advanced ultrasonics for thick composites. The results presented in this study demonstrate an inverse relationship between the ability to find delaminations and plate thicknesses, with inspections successful at depths up to 74 mm. When the delamination thickness exhibited surface-to-surface contact, the inspection capability was reduced to 35 mm. There was an exponential decay relationship between the accuracy of the flaw depth measurement and plate thickness, likely due to the necessity of low probe frequencies. The effective inspection depth was determined to be in the range of 1 to 20 times the wavelength. It is speculated that the accuracy of measurements could be improved using probes with novel coupling solutions, and detectors with optimised signal processing/filtration algorithms.

Polarization and relaxation mechanisms in glass fiber-reinforced LED-cured polyester composites incorporating graphene nanotubes

The current research aimed to understand how the polarization and relaxation mechanisms in light-emitting diode (LED) cured glass fiber reinforced polyester (GFRP) composites change with graphene nanotubes (GNTs). In this context, the complex permittivity (ԑ*), loss tangent (tanδ), AC electrical conductivity (σ), and complex modulus (M*) features of the samples were measured via impedance spectroscopy. According to the virtual electrical modulus values, electrical polarization occurred after the first peak at 127 kHz. With increasing GNT ratio, a polarization mechanism was obtained at approximately 350 kHz as a result of a shift towards higher frequencies. Although a significant change was observed in the electrical conductivity value as the frequency increased depending on the GNT ratio, there was no change in the conductivity values up to 10 kHz. At high frequencies, dipole formation and orientation occurred, resulting in an increase in conductivity up to 150 kHz.

A Comparative Study of the Static and Dynamic Characteristics of Jute and Glass Fiber-Reinforced Polyester Composites

A Comparative Study of the Static and Dynamic Characteristics of Jute and Glass Fiber-Reinforced Polyester Composites

Optimized Strength of Chopped Strand Mat Glass Fiber-Reinforced Polyester Laminates with Single-Edge Notch under the Effects of Notch Shape/Size and Strain Rate

Optimized Strength of Chopped Strand Mat Glass Fiber-Reinforced Polyester Laminates with Single-Edge Notch under the Effects of Notch Shape/Size and Strain Rate

Analysis of material removal process when scratching unidirectional fibers reinforced polyester composites

AbstractIn this study, the micromechanical scratch behavior of unidirectional glass fiber reinforced polyester (GFRP) using several wear conditions was highlighted. Single-indenter scratch tests (SSTs) were carried out on GFRP composite material perpendicular (SST⊥) and parallel (SST//) to fiber direction. Damage modes dominating the material removal process (MRP) and friction exhibit significant sensitivity to both attack angle and normal load. From findings, damage modes and apparent friction coefficient substantially accentuate when increasing the attack angle. The inspections of the damage state at different testing conditions using a scanning electron microscope (SEM) reveal the dominating modes governing the MRP through the different phases. The response surface methodology (RSM) was adopted to develop a mathematical model based on the measured data. The RSM approach was found very promoting for predicting friction evolution versus attack angle and normal load. The proposed model reveals good ability not only in predicting apparent friction coefficient but also in detecting separately its ploughing and adhesive component. To emphasize the correlation between friction coefficient and MRP, the wear maps have been drawn up.

A study of surface roughness and material removal rate for optimal parametric combination in turning of GFRP composites

High surface quality and/or dimensional accuracy of the products produced by machining plays an important role in the part performance. The use of polymer materials is gradually replacing that of metallic materials. Due to their anisotropy and non-homogeneity, their machining behavior differs greatly from that of normal metallic materials. Because the phenomena responsible for material removal while cutting fiber reinforced plastic composite materials and those of typical metals and their alloys differ fundamentally, particular attention must be paid to the choice of the proper tool and machining conditions. The present study examines various turning process parameters, including cutting speed, feed rate, depth of cut, and their significance in determining the surface roughness and material removal rate of glass fiber reinforced polyester (GFRP) tubes. The experimental work is carried out on a CNC lathe. After turning the external diameter of the workpiece according to predetermined turning conditions, average surface roughness (Ra) was measured, and material removal rate (MRR) was calculated. The study utilizes the methodology of Grey Relational Analysis (GRA) and Analysis of Variance (ANOVA) to determine the optimal parametric combination giving the smallest values of Ra and the highest values of MRR.

Physical analysis and statistical investigation of tensile and fatigue behaviors of glass fiber-reinforced polyester via novel fibers arrangement

Polymer composite researchers have extensively explored the influences of fiber orientation, volume fraction, type, length, as well as the impacts of matrix type, matrix/reinforcement interface, fibers hybridization, and nanoparticle incorporation on the mechanical behaviors of fiber-reinforced composite materials. The impacts of tailored fiber architectures on the mechanical characteristics of bulk polymeric-based composites, on the other hand, have not been investigated. The purpose of this research is to determine the effect of fiber arrangement on the mechanical characteristics of glass fiber-reinforced polymeric materials (GFRP). Unreinforced (UR) polyester, surface reinforced arranged (SRA) composites and bulk reinforced arranged (BRA) composites were fabricated. Characterizations have been performed using scanning electron microscope rotating bending fatigue machine and a universal testing machine. Results demonstrate that SRA’s lifespan after being exposed to bending fatigue has increased significantly with respect to UR and BRA samples. Average fatigue life for SRA samples is 61 times longer than the life of BRA samples at 56 MPa bending stress. Furthermore, a Weibull distribution function with shape parameter and scale parameter was implemented to analyze the fatigue life dataset statistically. The introduction of SRA novel design has promising results for cost reduction as well as quality improvement.

Development and Characterization of Phosphate Glass Fibers and Their Application in the Reinforcement of Polyester Matrix Composites.

This study focused on the production and characterization of phosphate glass fibers (PGF) for application as composite reinforcement. Phosphate glasses belonging to the system 52P2O524CaO13MgO (11-(X + Y)) K2OXFe2O3YTiO2 (X:1, 3, 5) and (Y:0.5, 1) were elaborated and converted to phosphate glass fibers. First, their mechanical properties and chemical durability were investigated. Then, the optimized PGF compositions were used afterward as reinforcement for thermosetting composite materials. Polyester matrices reinforced with short phosphate glass fibers (sPGF) up to 20 wt % were manufactured by the contact molding process. The mechanical and morphological properties of different sPGF-reinforced polyester systems were evaluated. The choice between the different phosphate-based glass syntheses (PGFs) was determined by their superior mechanical performance, their interesting chemical durability, and their high level of dispersion in the polyester matrix without any ad sizing as proven by SEM morphological analysis. Moreover, the characterization of mechanical properties revealed that the tensile and flexural moduli of the developed polyester-based composites were improved by increasing the sPGF content in the polymer matrix in perfect agreement with Takayanagi model predictions. The present work thus highlights some promising results to obtain high-quality phosphate glass fiber-reinforced polyester parts which can be transposed to other thermosetting or thermoplastic-based composites for high-value applications.

Experimental and statistical analysis of flexural behavior of glass fiber reinforced polyester (GFRP) molded grating panels

In this study, the full section of flexural and shear modulus of molded gratings made of glass fiber reinforced polyester (GFRP) have been statistically and experimentally analyzed. Three different gratings with slab height (h) of 25 mm, 30 mm and 38 mm were taken. The flexural (E) and shear modulus (G) of molded gratings were determined from the three-point bending tests by taking different grating span (L) - slab height (h) ratios ranging from 4 to 20 by four increments. Shear modulus was calculated from the test data by considering Timoshenko’s shear deformation beam theory (TBT). The flexural and shear modulus of the molded gratings were determined with a reliability of 99% by Weibull distribution. The results showed that E and G obtained from the Weibull analysis take their maximum values at h38 and h30, respectively. However, maximum mean values of E and G obtained experimentally are at h25 and at h38, respectively.

Flexural analysis of hemp, kenaf and glass fibre-reinforced polyester resin

Abstract Natural fibres have a high potential to replace synthetic fibres such as glass in a variety of applications. However, natural fibre-reinforced composites still have some limitations with respect to the mechanical performance especially in high load bearing capabilities. The hybridization of natural fibres with synthetic fibres in the same matrix has proven to create a balancing effect and enhanced the composites performance. Besides that, fibre architectures that include fibres continuity, fibres orientation, fibres arrangement and fibres interlocking are also considered to enhance the overall performance of the composites. In this study, the hemp mat, kenaf mat and glass chopped strand mat were hybridised with woven glass fibres, respectively in polyester resin to form 12 systems of the composites. The hybridization effects of different fibre core material, fibre core thickness and fibre arrangement on flexural response were investigated according to ASTM D7264. The results indicated that hybrid CSM glass/woven glass composite showed the highest flexural strength and modulus compared to hemp/woven glass and kenaf/woven glass composites, with about 377.15 ± 48.41 MPa and 16.74 ± 7.15 GPa. Among natural fibres, kenaf fibre (2WG/K/2WG) composite showed better flexural properties compared to hemp fibre (2WG/H/2WG) composite. 2WG/2G/2WG composites with two plies of CSM glass showed maximum flexural properties. As for hemp/woven glass and kenaf/glass hybrid composites, the flexural properties reached a maximum value in system arrangement of (2:1:2) but it reduced in the system arrangement of (2:2:2) and (2:4:2). On the evaluation effect of fibre arrangement, hemp, kenaf and glass mat used as core (arrange in the middle; (2:2:2)) showed higher flexural properties as compared to the use as skin (arrange in outer; (1:4:1)). (2WG/2K/2WG) showed better flexural properties than (2WG/2H/2WG) as the core, while (H/4WG/H) showed better flexural properties than (K/4WG/K) as skin.