Glass Fiber Reinforced Polymer Matrix Research Articles

Enhancing the Mechanical and Fire-Resistant Properties of GFRP Composite using Boric Acid and Sodium Silicate Fillers

This study investigates the effects of Boric Acid (BA) , H3BO3, and Sodium Silicate (SS), Na2SiO3, as single fillers on the mechanical and fire-resistant properties of Glass Fiber Reinforced Polymer (GFRP) composites. Various compositions of BA and SS were incorporated into the GFRP matrix, and the resulting composites were analyzed using X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermo-Gravimetric Analysis (TGA), and Differential Thermal Analysis (DTA). The results demonstrate that BA significantly enhances the amorphous structure and mechanical strength of GFRP composites, with optimal performance at 10% BA content. In contrast, SS improves thermal stability but reduces mechanical strength at higher concentrations due to agglomeration. Fire resistance testing revealed that both fillers increase the ignition time and decrease the burning rate, with BA exhibiting superior performance. These findings suggest that BA is a more effective filler for improving the mechanical and fire-resistant properties of GFRP composites, while SS can serve as a complementary additive to enhance thermal stability.

Acoustic Emission based determination of delamination initiation in GFRP laminates

Acoustic Emission (AE) has the potential to identify delamination initiation in quasi-static Mode I fracture tests on glass fiber-reinforced polymer-matrix (GFRP) laminates. It had been shown that a combined AE activity and intensity criterion yields critical Mode I delamination resistance values GIC for an AS4/PEEK carbon fiber thermoplastic composite that are comparable to those from data analysis according to ASTM D5528. However, the AE historic index also allows for detection of delamination initiation under Mode I and Mode II loading of carbon fiber reinforced thermoplastics and thermosets. In the present study, these AE criteria for initiation under Mode I, Mode II and Mixed Mode I/II loading of GFRP epoxy laminates are compared with AE signal energy as additional initiation criterion. Initiation under Mode II and Mixed Mode I/II at a ratio of 4:3 was determined with two different set ups for each Mode. For some test configurations noise signals make unambiguous initiation detection difficult. Determination by means of AE energy or AE activity and intensity yields more conservative GC values compared with the AE historic index or criteria defined in the standards, however, with similar repeatability.

Experimental and numerical analysis of drilled‐ and molded‐hole glass fiber reinforced polymer matrix (GFRP) composites

AbstractDrilling glass fiber reinforced polymer matrix (GFRP) composites typically causes burrs, splintering, and microcracks within the GFRP structure, as well as delamination, fiber pull‐out, and thermal degradation of the polymer matrix. Designing and manufacturing molded‐hole GFRP components, as opposed to drilling, has recently been proposed as a promising method for overcoming the issues associated with drilling, for which there is limited research. Specifically, the mechanical response of molded‐hole GFRP has not been fully addressed in the literature. In the present study, molded and drilled GFRP composites with epoxy matrix were fabricated by hand lay‐up, and then the samples were analyzed utilizing experimental and numerical analysis techniques. Stress and strain analyses of GFRP samples were performed in Ansys Transient Structural Analysis. Although the fiber orientations of the layer geometries [0°/90°] and 3D models were the same, an additional layer was defined in the direction of the fiber orientation [45°/−45°] of molded‐hole composites to simulate the fiber accumulation effect. Experimental findings revealed that the flexural strength of molded composites was 12% greater than that of drilled composites. According to the numerical analysis, 98.7% proximity was achieved between the experimental and numerical results. Thus, the present study has provided numerical modeling to understand the flexural strength of molded composites for the first time, which will contribute to the increased use of molded composites in numerous applications in the fields of aerospace, automotive, and marine.Highlights Drilled‐ and molded‐hole GFRP composites were produced by hand lay‐up. Flexural properties of the composites were examined via 4P bending tests. Flexural strength of molded composites was higher than that of drilled ones. 98.7% proximity was achieved between the experimental and FEM results. A unified FEM method is proposed for the molded‐hole composites.

Experimental Investigation on Thermal Behaviour of Silicon Carbide (SiC) based Polymer Composites under Hygrothermal Conditions

The thermal management of electronic devices is a critical component of their performance. Due to the emergence and evolution of new technologies, the wide use of electronic devices is increased in the past decade in the field of marine, automobile and other stationary applications. The need for effective thermal management in these applications has become more critical. This paper aims to provide a comprehensive overview of the various challenges that face the development of new composite materials, as epoxy-based composites are the latest trend of materials widely used in many areas. But their thermal conductivity behaves poorly in moisture and thermal conditions. This work attempts to study the behaviour of silicon carbide and E glass fiber reinforced polymer matrix composite under hygrothermal and compressive loads. Specimens are also tested for moisture absorption to calculate the hygro strains of a specimen. E-glass fiber is fixed to 15% and varied 10%, 20% and 30% of SiC in the fabrication of hybrid polymer composite using the hand-layup technique. These specimens undergo tensile, flexural, hardness and thermal conductivity tests, revealing the tensile strength, thermal, flexural strength, hardness and thermal conductivity of proposed specimens. The behaviour of the specimens is compared for all conditions with moisture at room temperature, 80 deg C and 150 deg C.

Study of the Behavior and the Mechanical Properties of Adhesively Bonded Polymer Matrix Composites Under Mechanical Loading

Glass fiber reinforced Polymer matrix composites (PMCs) have a complex set of properties - high specific strength and hardness, good corrosion and chemical resistance, and most of all low relative weight, making them the preferred material over metallic materials in a number of industries (aircraft, boat building, renewable energy facilities and many others). The main aim set in the present work was reduced to the obtaining of PMCs made by adhesive bonding of two composites with a matrix of different types of resin (vinyl ester and epoxy) and the study of their behaviour in determining their mechanical properties. The studies were carried out with four types of adhesively bonded PMCs made in the form of laminates produced from a combination of three types of resin (two types of vinyl ester and one type of epoxy resin) and reinforced with biaxial fiberglass. The aim is to combine the lack of shrinkage of the epoxy resin with the better mechanical properties and better productivity of the vinyl ester resin. An analysis to determine shear strength, tensile strength and bending strength of the investigated composites was made. A macrostructural fractographic analysis to investigate the material behaviour under mechanical loads was carried out.

Modeling and analysis of tapered composite beams with piezoelectric energy harvester: Numerical and experimental investigations

In the present study, a numerical and experimental investigation is carried out on vibration-based energy harvesting from unimorph cantilever tapered composite beams. A uniform and various configurations of a tapered composite structure embedded with piezoelectric material are considered to identify the electrical energy generated by the piezoelectric material when dynamic energy is imparted on the structure. Lead zirconate titanate (PZT) of 5-H grade piezoelectric material is considered to be embedded on a cantilever beam made of glass fiber reinforced polymer matrix composite. The numerical modeling and analysis are performed on the composite structure embedded with PZT to calculate the total amount of electrical energy that can be generated by the PZT material using commercially available ANSYS APDL software. Various parametric studies are also carried out to investigate the effects of varying the location of the PZT patch and the configuration of the PZT patches on the electrical energy developed by the PZT. Further, the power generated through unimorph composite structure with PZT material connected in series and parallel are explored.

Perforation Effect of Continuous Laser on Glass Fiber Reinforced Polymer Matrix Composites Under Subsonic Tangential Airflow

Perforation Effect of Continuous Laser on Glass Fiber Reinforced Polymer Matrix Composites Under Subsonic Tangential Airflow

Investigation on tensile behavior of glass-fiber reinforced polymer matrix composite with varying orientations of fibers

The main objective of this work is to develop a new polymer based composite material having different reinforcement angle orientations and studies its tensile behavior. For fiber reinforced polymer matrix composites E-2 glass fiber reinforcement and epoxy resin for matrix is used. E-2 g1ass fiber has high strength, chemical resistance and good insulating properties. Epoxy being less viscous allows good adhesion to fibers used in laminate preparation, without misalignment of fibers. Hand layup technique has been adopted for preparation of laminate. Glass fibers are laid, mixture of epoxy resin and hardener is smeared on it alternately, until laminate of desired thickness is achieved, and is left to atmosphere for curing. 2.5 mm laminate is prepared by placing glass fibers of 0.25 mm thickness one above the other. The prepared laminate is then taken for cutting according to ASTM standards (D3039) of 3 sets of rectangular specimens. For first set comprises of 90° angle-oriented specimen, second and third sets for 45° and 30° respectively. These specimens are subjected to tensile test in Lloyd UTM and load being applied gradually at the rate of 2 mm/min is continued until the material fails. The computer simulation plots the graph during the entire testing process and stops when the material fails.

Study on flexural behavior of glass-fiber reinforced polymer matrix composite

The primary goal of this research is to analyze a new polymer-based composite material with various reinforcement angle orientations and to investigate its flexural behavior. E-2 glass fiber reinforcement and epoxy resin for matrix are used in fibre reinforced polymer matrix composites. Three sets of rectangular specimens are prepared according to ASTM standards (D7264). First set comprises of 30° angle-oriented specimen, second and third set comprises of 45° and 90° respectively. These specimens are subjected to flexural test in UTM and load being applied gradually until the material fails. It is evident from the results that the load bearing capacity of 90° orientation laminate is more when compared to 30° and 45°.These experimental results are compared with FEA results and found to have a good correlation.

2 Way Fluid-Structure Interaction Study of a Wing Structure

Abstract: In this paper a scaled down model of a wing of rectangular planform is designed and the static analysis on the wing is carried out to determine the aerodynamics forces, stresses acting on it and the frequency of various modes. The iteration for the analysis is carried out for three materials namely, Aluminium 7075 T-6, Glass Fibre Reinforced Polymer and Aluminium Metal Matrix Composite. The analysis in the coupled mode is conducted and compared with the results obtained from that of static analysis to observe the changes in the flow pattern and how the structure behaves when the wing is considered to be flexible. In the coupled mode analysis 2 Way Fluid Structure Interaction analysis is carried out. The material properties and the results obtained from the analysis is compared to select the best out of the three materials. The change in the aerodynamic properties of the wing when it is considered to be flexible is also highlighted by a method of comparison. From the results obtained, it is observed that Aluminium Metal Matrix Composite has the least deformation for the same loading and can withstand higher stress. Hence, Aluminium Metal Matrix Composite exhibits better characteristics in comparison with Glass Fibre Reinforced Polymer and Aluminium 7075 T-6. Additionally, it is noticed that the aerodynamic properties of the wing is reduced when it is considered as a flexible structure. This can be highlighted by the 5.42% decrease in the L/D ratio between the CFD analysis and the 2 Way FSI analysis results. Keywords: Fluid Structure Interaction; Flexible Wing; CFD; Coupled Mode Analysis;

Effect of Span Length on Flexural Strength of Glass Fiber Reinforced Polymer Matrix Composite

Investigation and assessment of mechanical properties for FRP (Fiber Reinforced Polymer) composites have been instrumental in qualifying it for the final use. Pronounced among mechanical properties is flexural strength which diversifies with varying test span length, Specimen depth and temperature for different materials. Current work focuses on unearthing the optimum span length of epoxy Glass fiber reinforced composites for which flexural strength is to be scrutinized. Investigations for flexural test in accordance to ASTM Standard D790 are executed by altering the span lengths to acknowledge the functioning of the flexural modulus and strength thereby acquiring an optimum span length, which, can be employed by the composite designers and manufacturers to engineer meliorated testing procedures. From the experimental results it is found that the composite failed by shear mode at lower span lengths.

Strength degradation of glass epoxy composites under hygrothermal environment

The composite structures are being used in marine applications like boat hulls, propeller blades etc. Apart from these, the composites are used as structural materials exposed to different kinds of degrading environment like temperature and relative humidity. When a fiber-reinforced composite structure is exposed to a hygrothermal environment and mechanical loads, changes in material properties are related to irreversible material strength degradation. The present study deals with the mechanical strength degradation of glass fiber reinforced polymer matrix composites when subjected to hygrothermal environment. The composite cross ply laminates were manufactured by using compression molding process with two types of curing processes cold press and hot press with a bi-directional E-Glass WR 360 as reinforcement, LY556 as resin and HY951 as hardener. The mechanical properties such as Tensile, ILSS, moisture absorption was investigated with different temperatures like 32 °C, 50 °C and 85 °C with time holding of 30 min, 60 min and 90 min in 5% of brine solution. The same mechanical properties are compared with specimens under sealed condition with unsealed condition.

Mode-I fracture toughness of glass/carbon fiber reinforced epoxy matrix polymer composite

Abstract Advanced polymer composites such as continuous fiber-hybrid reinforced composites results in significant increase in fracture toughness and strength when compared with conventional composites. In this recent research plane strain or mode-I (tensile) fracture toughness of the glass fiber reinforced polymer matrix composite, carbon fiber reinforced polymer matrix composite and hybrid polymer composite (with glass and carbon fiber reinforcements to epoxy matrix) along with its interlaminar shear strength and flexural strength has been evaluated and discussed. Scanning electron microscopic images were also used to analyze the fracture behavior of these composites. The obtained results are analyzed to evaluate: (i) effect of glass fiber and its influence on the flexural strength, interlaminar shear strength and mode-I fracture toughness, (ii) effect of carbon fiber and its influence on the flexural strength, interlaminar shear strength and mode-I fracture toughness, and (iii) finally, properties of hybrid composite. The results thus obtained have revealed that the mode-I or plane fracture toughness is significantly enhanced with the reinforcement of carbon fibers. In hybrid composite fracture toughness is greater when compared with their bulk and monolithic counter parts.

Machinability and Delamination Studies on Glass Fiber Reinforced Polymer Matrix Composite Cut by Abrasive Water Jet Machine

Abrasive water jet machining possesses inherent technological and manufacturing advantages unmatched by most machine tools. They are generally used in automotive, marine and aerospace industries for machining of composites. However, abrasive water jet cutting of GFRP laminates possesses several challenges, such as surface finish and delamination of the cutspecimen. Henceforth, more experimental work is needed to provide sufficient machinability databases for manufacturing industries. This paper presents an experimental study for cutting GFRP laminates. Different AWJM conditions including pressure, traverse speed and abrasive flow rate are analyzed using full factorial design of experiments. Machining process responses such as surface roughness (Ra), top and bottom kerf width, kerf taper, delamination of fibers have been evaluated using analysis of variance (ANOVA) technique. The optimum process parameters for AWJM of glass fiber reinforced polymers have beensuggested.

Artificial Neural Network and Response Surface Methodology Based Analysis on Solid Particle Erosion Behavior of Polymer Matrix Composites.

Polymer-based fibrous composites are gaining popularity in marine and sports industries because of their prominent features like easy to process, better strength to weight ratio, durability and cost-effectiveness. Still, erosive behavior of composites under cyclic abrasive impact is a significant concern for the research fraternity. In this paper, the S type woven glass fibers reinforced polymer matrix composites (PMCs) are used to analyze the bonding behavior of reinforcement and matrix against the natural abrasive slurry. The response surface methodology is adopted to analyze the effect of various erosion parameters on the erosion resistance. The slurry pressure, impingement angle and nozzle diameter, were used as erosion parameters whereas erosion loss, i.e., weight loss during an erosion phenomenon was considered as a response parameter. The artificial neural network model was used to validate the attained outcomes for an optimum solution. The comparative analysis of response surface methodology (RSM) and artificial neural network (ANN) models shows good agreement with the erosion behavior of glass fiber reinforced polymer matrix composites.

Effect of Stacking Sequence on Interlaminar Shear Strength of Multidirectional GFRP Laminates

Abstract Glass fiber reinforced polymer matrix composites are widely used in many applications such as aerospace, automobile, marine, electrical etc. because of its superior mechanical property coupled with minimum weight requirements of the component. The performance of a composite part gets mostly affected by the residual stresses, stacking sequences due to relation with in-plane stresses. This study investigates performance of multidirectional laminates using bi-directional plain-weave glass fabric, the alteration in stacking sequence is done in, in-between plies, keeping inner and outer ply orientation constant. Laminates are made by hand layup and compression moulding technique. Five class of laminate, keeping stacking sequence of [0°/(0°)2/0°]S, [0°/(15°)2/0°]S, [0°/(30°)2/0°]S, [0°/(60°)2/0°]S, [0°/(75°)2/0°]S are manufactured and tested for interlaminar shear stress using ASTM D2344-16 standard on fully computerised UTM with strain rate of 1 mm/s. It is seen that laminate performance exhibits dependency on orientation of in between plies. The Laminates with all plies oriented in 0° position depicts lowest ILSS whereas the laminate having 60° ply in between possesses highest ILSS

Analysis of behavior of composite material during loading tests

Composites are widely used as a material suitable for construction applications, but the operating conditions can lead to reduction of materials properties, damage initiation and collapse of the structure, so it is necessary to monitor condition of components and thus prevent its catastrophic failure. The unidirectional glass fiber reinforced polymer matrix composite (GFRP) was inspected with usage of non-destructive (NDT) acoustic emission during the static loading tests. The 0° test specimens were manufactured and tested under tensile and three-point flexural load for which the custom-made apparatus was used. Failure mechanisms were inspected by detailed analysis using scanning electron microscopy (SEM) to deduce the damage sequence. Tensile stress-initiated matrix cracking which induces formation of scarps, ribbons and riverlines followed by delamination and fiber failure with formation of radials. Flexural load showed cracks in matrix, delamination and typical compression regions in form of fiber microbuckling. Based on the speed of wave propagation and linear localization, damage processes were detected in form of lateral cracking, delamination and integrity loss during the tensile and flexural tests. The data obtained from mechanical testing were correlated with selected acoustic emission parameters (counts, events, amplitude and duration). Behavior of GFRP material during the tensile test can be described very well with usage of counts while the flexural test provides much less information. The evaluation of damage processes using event parameter based on the amplitude and duration proved to be problematic due to the noise interference. The Short-time Fourier transform (ST-FFT) and peak frequency was used for identification of failure modes. In case of tensile and flexural load the matrix cracking has lower frequencies while delamination and fiber failure have higher values.

Stress Field Analysis of Polymer Composite with Orthogonally Reinforced Fibers

The photoelastic technique was used to analyze the stress field in glass fiber reinforced polymer matrix composite. Two glass fiber bundles with a diameter of 0.2 mm were reinforced in orthogonal directions. The composite was subjected to diametrical compression with two orientation of fibers with respect to the loading axis, i.e. 00/900 and 450/1350. A circular polariscope with dark-field arrangement was used to analyze the stress field. The isochromatic fringe pattern nearby fiber/matrix interface revealed that there was strong adhesion between the fiber and matrix. Distorted fringes were observed nearby fiber region which indicated efficient load transfer from matrix to the fiber. It was observed that composite with 450/1350 orientation of fibers showed more principal stress difference in the direction perpendicular to the loading axis.

A Comprehensive Study of Glass Fibre Reinforced Polymer (GFRP) Drilling

Machining is one of the most common subtraction manufacturing process, wherein the final shape of the product is obtained by removing of excess material from the work part. The rising demand for high performance structural material necessitated the development of composite materials and like any other engineering material, to be a part of final assembly, the composites are also required to undergo the machining processes. The most common machining operation is the mechanism of making hole, known as drilling. The drilling of fibre reinforced polymers (FRPs) distinctively differs from that of the drilling mechanism in conventional metals, due to the prior’s inhomogeneous nature. The machining quality for drilling composites is quantified through surface roughness (surface morphological issue) and the delamination (surface integrity issue). The article presents a comprehensive analysis of the effect of various parameters viz. drill tool material and drill process parameters on the said machining quality factors, whilst drilling of glass fibre reinforced polymer matrix composites

Mechanical properties and abrasion behaviour of glass fiber reinforced polymer composites – A case study

Abstract Glass fiber reinforced polymer matrix composites have enticed the researchers since last few decades, due to their excellent mechanical properties and wear resistance behaviour. In this paper woven roving E-glass fiber reinforced epoxy resin composite was prepared by hand lay-up method, followed by curing at 140 °C for 6 h. Density, porosity and different mechanical properties, such as hardness, tensile strength and impact strength were evaluated experimentally, and the test results were compared and validated with the experimental results of open literature. Three-body dry abrasion behaviour of the composite sample was also investigated.