Fiber Epoxy Research Articles

Composite interlaminar fracture toughness imparted by electrospun PPO veils and interleaf particles: A mechanistical comparison

Thermoset composite toughening by interleaf materials receives increasing attention as requirements for high toughness become essential for primary structures. Here, polyphenylene oxide (PPO) electrospun veils were used for carbon fiber epoxy composite interleaf toughening. Their Mode I, Mode II interlaminar fracture toughness (GIC and GIIC) were measured as a function of veil loading levels. 10 wt% veil loading rendered the best toughening performance, reached to 530 J/m2 and 1400 J/m2 in GIC and GIIC, respectively, and it yielded further increase of 140% and 30% compared to the corresponding PPO particles. Scanning electron microscopy (SEM) and 3-D laser microscopic imaging analysis (3D-LMIA) on fracture surfaces revealed energy absorbing mechanisms such as bridging and plastic deformation. The continuous network structure imparted by the veils accounted for the additional toughening mechanisms, i.e. the deformation, breakage and pull-out of PPO fibers, that were responsible for the outstanding fracture toughness.

Experimental investigation of RHA biochar and tamarind fibre epoxy composite

In this investigation, neem chip biochar and tamarind seed fibers were utilized to produce the hybrid-based polymer matrix composites by the epoxy resins. The main objective of this study was to improve the composite property using eco-friendly fillers. There are four various arrangements of proportions were made the composite specimens. The composites were cured using hot air oven at the temperature 120 °C. Then the mechanical testing like tensile, impact and hardness strength was attained on the fabricated polymer matrix composites specimens. Finally, increasing biochar improves the hardness and adding tamarind seed fibers made better tensile and equal proportions of biochar and tamarind seed fibers formed the superior impact strength, respectively.

Nano-graphene E-glass fibre epoxy polymer composite thermal and mechanical characteristics study

The mechanical and thermal characteristics composites reinforced with E-glass fibre were examined in the current study. The mechanical stirring technique followed by the hand layup method was used to make composites loaded with different weight percentages of nanographene and a layer of e-glass. Nano-composite is made up of three different compositions by adjusting the weight percentages of each nanomaterial by 1%, 2%, and 3%. The generated nanocomposites' mechanical characteristics, including flexural strength, tensile strength, TGA, DTA, DSC, and hardness, were investigated and compared on a varying of nanofillers. The results showed that, when compared to neatly stacked composites, the introduction of nanographene (NG) composites can be a successful strategy in terms of mechanical qualities. Results are presented after examination of the experimental values of 1, 2, and 3 wt% of nanographene in the E-glass fabric reinforced composite. Additionally, it was found that adding nanomaterials the mechanical and thermal properties of nanographene to decrease after reaching their optimum weight percentage.

Flexural behavior of natural fiber epoxy composites

Flexural behavior of natural fiber epoxy composites

Realization of mechanical and tribological properties of hybrid banana, sisal, and pineapple fiber epoxy composites using naturally available fillers

In recent days the use of Natural fiber-reinforced composites in all sorts of consumer goods. A wide variety of technologies necessitate the use of materials with unusual property combinations, such as high strength-to-weight and stiffness ratios. Traditional metal alloys fall short of these quality standards, which has led to a significant increase in the applications of natural fibers. Hence, an effort has been made to investigate the effect of fillers like Coconut shell (CS), Saw dust (SD), Kolam (KP), and Fly ash powder (FA) on the mechanical and wear properties of Epoxy reinforced hybrid Sisal, Banana, and Pineapple fiber composites in this work. The Natural fibers weight percent was taken around 45 wt%, with the same quantity of epoxy blended with 10 wt% Naturally available fillers. The findings revealed that the CS fillers in the composite have a more positive influence on tensile strength and modulus than the composite with other fillers which are used in this study. SEM analysis of tensile-fractured CS specimens also reveals an improved fiber-matrix bonding. Similarly, the CS-filled composite also exhibits better flexural strength, modulus, and Impact strength maximum of up to 18% higher than the BS, SD, KP, and FA-filled Hybrid composites. Further, CS-filled composite has reduced weight loss against wear and friction due to higher lignin content.

Abrasive water jet machining of pineapple fibre epoxy composite at high transverse speed

Recently, research has been undergoing in the area of natural fibre-reinforced composite as an alternative for metals and plastics in automobile applications. It is mainly because of its strength and lighter weight. Literature shows that tribological studies are made in large numbers to evaluate these composite's strength, corrosion and wear behaviour. The machinability of these natural fibres is to be studied to understand the further scope of these materials in their respective application. In this research machinability of pineapple fibre is studied under the abrasive water jet machining process at a higher transverse speed. The material removal rate is chosen as a tool for evaluating the machinability of these composites. The Taguchi-based approach is used for planning and optimising the experiments. The optimal parameter for maximising the material removal rate is done using the signal-to-noise ratio analysis. Also, an Artificial neural network algorithm is developed to predict the responses. The results of the ANN model show that the model predicts the response with an accuracy of 94.9%. This ANN prediction model of machining study could be helpful when these composites are imposed in automobile and aerospace applications.

Manufacturing and damping properties of microflake–nanoflake reinforced carbon fiber epoxy resin matrix composites

Due to the high strength, high modulus, lightweight and other characteristics, carbon fiber reinforced polymer (CFRP) is widely used in aerospace, high-speed aircraft, and other fields. In this article, a high-damping CFRP reinforced by flake polyurethane fillers is prepared with good mechanical properties, and the effects of flake polyurethane fillers on the mechanical and damping properties of CFRP are studied. The results show that the mechanical and damping properties of CFRP could be significantly improved by the appropriate content of the flake polyurethane fillers. In addition, the optimal content of the flake polyurethane fillers is 3 wt.%, and the flexural strength, interlaminar shear strength, and damping properties of CFRP are increased by 6.19%, 12.07%, and 9.48%, respectively.

Experimental Investigation on Physical Properties of Concrete Containing Polypropylene Fiber and Water-Borne Epoxy for Pavement

Cement concrete pavement accounts for a large proportion of the road network due to its excellent mechanical strength and durability. However, numerous microcracks are generated due to the high brittleness of concrete, which poses a threat to the service life of concrete pavement. Currently, simultaneous addition of fibers and polymers is a feasible approach to resolving the issues associated with the brittleness of concrete. This study explores the properties of concrete mixtures containing different levels of polypropylene fibers and water-borne epoxy. Additionally, fly ash is also introduced to concrete mixtures. The tests performed include slump, compressive strength, flexural strength, shrinkage, depth of water penetration, and abrasion. The results indicate that water-borne epoxy, at all levels, contributed to improving the weak interfacial bonding between polypropylene fibers and concrete. In addition, the combined incorporation of polypropylene fibers and water-borne epoxy could improve the mechanical and durability properties of concrete, with the combined utilization of 0.1% polypropylene fibers and 10% water-borne epoxy exhibiting the best performance. Moreover, with the incorporation of 10% fly ash into concrete, the mechanical strength and abrasion resistance experienced a slight reduction, while the workability, drying shrinkage resistance, and impermeability were improved. The current findings indicate that the combined utilization of polypropylene fibers and water-borne epoxy at appropriate levels is beneficial for application in pavement; however, in spite of superior drying shrinkage resistance and impermeability, the incorporation of fly ash into concrete pavement should be properly treated according to the actual engineering conditions.

Mechanical and thermal properties of carbon fiber epoxy composite with interlaminar graphene at elevated temperature

In this study we examined the mechanisms of graphene reinforcement in CFRP and the resulting improvements to mechanical strength, resistance to crack propagation, and thermal conductivity at elevated temperatures. Plant-based graphene nanoplatelets (pGNP), produced from renewable biomass and with flakes 3–10 layers dispersed in alcohol/water was applied via spray at 2.3 g/m2 to unidirectional carbon fiber/epoxy prepreg, creating an interlaminar nanocomposite. Raman spectroscopy, XPS, and DMA show polymer crosslinking with graphene surface groups and the resulting restriction of side chain movement. These restrictions improve composite performance at ambient and elevated temperatures, extending the damage process zone and increasing fracture toughness. Interlaminar pGNP improved Mode I fracture toughness at crack initiation by 145% at 20 °C and 126% at 90 °C, with fracture toughness improved by 53% and 52% during propagation at 20 °C and 90 °C, respectively. Mode II fracture toughness was not changed at 20 °C and improved 55% at 90 °C.

Damage progression monitoring using self-sensing capability and acoustic emission on glass fiber / epoxy composites and damage classification through principal component analysis

In this study, the synergistic combination of acoustic emission (AE) and self-sensing capability provided by the integration of carbon nanotube (CNT) networks was used to a better damage progression monitoring of glass fiber epoxy composites under flexural loading. The specimens were prepared with different stacking sequences ([06], [04], [0/90]S, and [90/0]S) using the vacuum assisted resin infusion procedure. The acoustic signals recorded during the tests were analyzed by a classification methodology which consists of the k-means method and principal component analysis (PCA), this analysis allowed the identification of the various damage mechanisms such as matrix cracking, fiber/matrix debonding, delamination and fiber breakage. The electromechanical response, through the change in electrical resistance signal, and some AE parameters such as the cumulative energy and/or strength cumulative were able to capture the occurrence of specific failure events during the composites damage evolution. Damage evaluation of failed specimens by means of scanning electron microscopy was performed, and it exhibited a less damage severity on specimens with CNT due to the reinforcement effect. This work demonstrates the complementarity of both non-destructive inspection techniques for monitoring damage progression in composite structures.

Effective utilization of waste sugarcane bagasse filler-reinforced glass fibre epoxy composites on its mechanical properties - waste to sustainable production

Effective utilization of waste sugarcane bagasse filler-reinforced glass fibre epoxy composites on its mechanical properties - waste to sustainable production

Characterization of epoxy resin based banana fiber reinforced composite with waste CD powder filler

In this day and age, where everything is driven by technology, the useful lifespan of items and devices is becoming increasingly shorter, which results in an increasing amount of electronic trash. The number of compact discs (CDs) that are produced each year is in the billions, but millions of them are simply discarded. They are eventually disposed of in landfills or by open burning, both of which result in unneeded harm to our environment, as well as the waste of energy and the loss of important resources. Additionally, the field of natural composites has attracted a lot of attention recently due to the fact that these composites are simple to mould, economical, and friendly to the environment. People are becoming more and more interested in natural -reinforced polymer composites because of how well they work in regards to their mechanical properties, how well they resist chemicals, how cheap they are, and how light they are. Efforts have been made to reuse the waste CDs in powder form as a filler material that can be used in engineering applications. Banana fibre fabric, epoxy, and waste CD powder were used to fabricate the composite. Waste CD powder was added in 5%, 10% and 15% by weight of banana woven fiber. Mechanical properties are determined by subjecting the material to standard tests for tensile strength, flexural strength, and impact strength. Using a scanning electron microscope, the surface of the object is analysed for its morphology in addition to its mechanical properties. Adding 10% of CD filler give better results. The experiment showed that woven banana fiber, when combined with waste CD powder, can function quite well as reinforcements in an epoxy matrix. Even though the mechanical properties of these composites are lower than those of the glass–epoxy combination, they can still be used in situations where more strength is not needed.

Characterization of optical ae signals at loading of fibre reinforced composites

Characterization of acoustic emission (AE) signals in loaded materials can reveal structural damage and consequently provide early warnings about product failures. Therefore, extraction of the most informative features from AE signals is an important part of the characterization process. This study considers the characterization of AE signals obtained from bending experiments for biocomposite and glass fiber epoxy (GFE) composites at room temperature and low temperature. For the acquisition of AE signals, fiber optic sensors (FOS) are used that can outperform classical electrical sensors under challenging operational environments. In this paper, we propose the extraction of deep features using different machine learning methods. The deep features are compared with extracted standard AE features. Then, the different feature sets are analyzed through discriminant analysis, neural networks, and extreme learning machines, combined with feature selection, to estimate the predictive potential of various feature sets. The proposed signal processing structure is focused on the classification of AE signals to recognize the source material, evaluate the predictive importance of extracted features, and evaluate the ability of used FOS for evaluation of material behavior under challenging low-temperature environments.

Characterization and predictive modeling of thermally aged glass fiber reinforced plastic composites

Glass fiber reinforced plastics (GFRP) are exposed to thermal aging in their widespread aerospace applications. Evaluating the effect of mechanical properties due to thermal aging has remained a challenge. An experimental investigation to characterize the thermal aging effects of glass fiber epoxy composites as well as the development of a predictive modeling is presented here. Tensile test samples have been thermally aged at 50°C, 100°C, 150°C and 200°C for 30 mins, 60 mins, 90 mins and 120 mins. At higher temperatures, the samples have shown a gradually increasing brown color while emitting a burning smell. The tensile test shows that the UTS value decreases as the thermal aging temperature increases. The predictive model has been prepared by combining image processing, regression analysis and two cascaded artificial neural networks (ANNs). The model reads the photographic image of the sample and uses the color change as an identifier. Cascaded ANNs estimate the thermal aging temperature and time from the image processing program. Finally, the ANN’s output is forwarded to the developed regression equation to get the estimated UTS. The predictive model’s estimated UTS shows an average accuracy of 97% when compared to the experimental results.

Enactment of Fiber Reniforced Hybrid Epoxy Composite for Passenger Car Bumper Beam

These days, fuel economy and emission petrol control of passenger vehicles are two critical challenges. The most effective approach to improve fuel efficiency with the front and rear parts of a vehicle are equipped with bumpers, which are crucial in low-speed collisions because they serve as low-speed energy absorbers. Sacrificing safety is to employ fiber reinforced composite materials in the body of cars. The fascia is a major element that is designed to absorb abrupt or impact loads that are imparted to automobiles either purposefully or accidentally. The objective for the incorporation of the bumper is when a collision suspends a vehicle to abrupt or impact loads, it is employed to absorb crash energy and is beneficial again for safety of the driver passengers as well as for the vehicle. In this work, a novel composite bumper beam which will be made of hybrid (natural and synthetic) fiber epoxy composite material embedded with multi walled carbon nanotubes to improve the bending stiffness. The major goal of the current investigation is to determine the impact of nano carbon tubes on the mechanical characteristics of jute/glass/epoxy hybrids and banana/glass/epoxy hybrids. The samples manufactured using a hand layup method and a variety of stacking sequences. Experimentations for three quasi-static 3-point bending test as well as fracture toughness will be conducted. Also, water absorption capability in reinforced materials will be measured. Based on the results, the bumpers are proposed for the Indian passenger cars.

Experimental Study on Woven Ramie Fibre Epoxy Composite with Silane-Treated Groundnut Shell Powder as a Filler Material

Experimental Study on Woven Ramie Fibre Epoxy Composite with Silane-Treated Groundnut Shell Powder as a Filler Material

The dependence of interfacial shear strength on temperature and matrix chemistry in glass fibre epoxy composites

The present work focuses on a fundamental investigation into the influences of the chemistry of epoxy and the testing temperature on the stress-transfer capability of the fibre-matrix interface in a glass fibre reinforced epoxy composite. We discuss how the interfacial shear strength (IFSS) is influenced by the hardener-to-resin ratio, testing temperature and fibre silane coating respectively. It was observed that the IFSS showed a significant inverse dependence on testing temperature for both silanes, with IFSS values dropping as the temperature was increased, for all ratios studied. Notably, it was shown that once the testing temperature was raised above the glass transition temperature that ratios possessing excess amine hardener had larger IFSS values. From the results presented it is hypothesized that residual radial compressive stresses at the interface are influenced by the chemistry of the matrix system and then relax away at the higher testing temperatures.

A comparative study on surface roughness of a novel Snake grass fiber/Aluminium powder reinforced epoxy composite and Snake grass fiber epoxy composite

The main objective of this study is to evaluate the surface roughness of a novel Snake grass fiber/Aluminium powder reinforced epoxy composite and compare it with Snake grass fiber epoxy composite in drilling process. In this work, the Snake grass fiber epoxy composite was taken as a control group with (N = 20) sample specimens. Also, Snake grass fiber with 20 % filler reinforced epoxy composites was considered as an experimental group with (N = 20) sample specimens. Composites plates were prepared with the hand layup method by various volume fractions of 0 % (without filler), 20 % Aluminium powder novel synthetic-filler. Surface roughness of the Snake grass fiber 20 % filler reinforced epoxy composite is 3.72 µm. Snake grass fiber with 20 % filler epoxy composite is 4.20 µm. Snake grass fiber with 20 % filler has statistically significant p = 0.024 (p < 0.05) than Snake grass fiber epoxy composite. Within the limitations of this study, the surface roughness of Snake grass fiber with a 20 % volume fraction of aluminum powder filler reinforced epoxy composite exhibited better significance than the Snake grass fiber epoxy composite.

Effect on Strength of Different Fiber Orientation Angles of the Composite Plate Under Out of Plane Load

Composite materials obtained by combining two or more materials macroscopically; It is expressed as a new type of material with low specific gravity, high strength and high rigidity properties. Composite materials are materials that are used under different loads and can be produced in various constructions. In this study, the effects of fiber orientation angle degrees on stress and deformation in composite plates with different fiber materials were investigated using the finite element method. Graphite, glass and aramid as fiber materials; Epoxy was chosen as the matrix material. According to the analysis results, while the stress and deformation values increased as the fiber angle increased in the graphite and aramid fiber epoxy matrix composite plates, the stress and deformation values did not change at different fiber angles in the glass fiber epoxy matrix composite plate.

Mechanical, wear, thermal and hydrophobic behavior of novel alkali‐silane treated palmyra sprout fiber and red matta biosilica epoxy biocomposite

AbstractIn this current study, high‐toughness epoxy bio‐composites were prepared and characterized for lightweight and low‐cost technological applications using novel palmyra sprout fiber (PSF) and red matta rice husk (RHA) biosilica. The principal aim of this research was to study how the alkali‐silane treatments on the fiber and particle influence the mechanical, wear, thermal and hydrophobic behavior of epoxy composites. The PSF was alkali‐silane treated whereas the biosilica was treated only with silane. The composites were prepared via a hand layup process and characterized. According to the results, the treated PSF with 3 vol.% RHA biosilica has the maximum tensile, impact, flexural strength, and hardness. The composite with the inclusion of 5 vol.% biosilica, and the palmyra sprout fiber has the lowest specific wear rate and COF of 0.007 mm3/Nm and 0.37. Moreover, these composites possess good thermal stability with the highest initial decomposition temperature of 342°C. Similarly, the composite designation ESP3 have the lowest contact angle of 75.7°, which is within the hydrophobic limit. These composites with improved mechanical, thermal and wear properties may be useful in a variety of engineering applications that can be used for high load‐bearing capacity and biodegradability, such as sporting goods, automobiles, home furniture, food packaging, transport, and aircrafts.