Epoxy Hybrid Composites Research Articles

Evaluation of EPDM waste in environmentally friendly epoxy hybrid composites

This study aims to reduce the production cost of composite materials, obtain composite materials with improved properties, and expand the applications of waste rubber composites using two different industrial wastes, ethylene-propylene-diene monomer rubber (EPDM) and tire waste pyrolysis solid product carbon black (CB). Composites were formed by adding EPDM waste or EPDM-CB mixture at 1:1, 1:3, and 3:1 ratios to bisphenol-A type epoxy resin in different weight ratios. Mechanical, water sorption, electrical conductivity, and flammability tests were applied to the composites. The effect of the EPDM:CB ratio and some environmental conditions on the mechanical properties of the hybrid composites were investigated. Composites with 3:1 weight ratio of EPDM:CB had the highest tensile strength, which varied between 115.5–158.6 MPa. Increasing the EPDM ratio in an epoxy matrix and hybrid filler decreased the composites’ density and tensile strength. EPDM-CB hybrid filler increased the thermal strength of epoxy. Mechanical properties are affected by water sorption, low temperature, and UV irradiation. Increasing the CB ratio in the hybrid filler decreased the flammability of the hybrid composites. ANOVA is applied to find the significant effect of different weight percentages of hybrid fillers and different varieties of fillers on the mechanical properties of composites.

Red mud waste/nanoclay/polystyrene‐modified epoxy hybrid composites: Mechanical, thermal, and flammability properties

AbstractIn this study, bisphenol A‐type epoxy (ER) and epoxy phenol novolac resins (EPN) with two amine‐type curing agents (KH 816 and IPOX EH 2041) having different total amine values were selected. The mechanical properties and density of the EPN resin were found higher in the case of both curing agents. EPN was modified with polystyrene (EPN‐PS) and used as a matrix using an IPOX hardener. Nano‐ and hybrid composites were prepared with pristine and modified with tetramethylammonium chloride nano montmorillonite (NC and MNC), and red mud waste (RMW). The chemical structure was elucidated by the Fourier transform infrared (FT‐IR). The composites were characterized by scanning electron microscopy and x‐ray diffraction. Appropriate PS and NC ratio was accepted as 4% and 2% by weight, respectively. Curing degrees calculated from the FT‐IR spectra of ER, EPN, and EPN‐PS were 99.3%, 99.9%, and 86.5%, respectively. A comparative study of the two binary systems; (i) 2 wt% NC‐(15–35) wt% RMW; and (ii) 2 wt% of MNC‐(15–35) wt% of RMW on the mechanical, thermal, and flammability properties of EPN‐PS matrix was carried out. The appropriate RMW ratio was 30 wt%. Hybrid composites with 25–30 wt% RMW can be considered self‐extinguishing materials.

Synergetic effect of graphene particles on novel biomass–based Ficus benghalensis aerial root/flax fiber–reinforced hybrid epoxy composites for structural application

Synergetic effect of graphene particles on novel biomass–based Ficus benghalensis aerial root/flax fiber–reinforced hybrid epoxy composites for structural application

Investigation of tensile and flexural properties of habesha moringa‐bamboo fiber reinforced epoxy hybrid composite

AbstractIn the present investigation, moringa oleifera and bamboo fibers extracted from Ethiopia are studied to understand their mechanical properties. Three types of woven composites namely moringa/epoxy, bamboo/epoxy and moringa/bamboo/epoxy (hybrid) are fabricated by maintaining 60 vol% fiber content. Additionally, neat epoxy samples are prepared for comparison. Tensile and flexural properties are investigated in terms of strength and modulus. Tensile test results depict brittle failure for all composites and infer increase in fracture strain of woven composites as compared with neat epoxy. Tensile modulus and strength of woven composites increase in the range of 19%–39% and 18%–281%, respectively as compared with neat ones. Flexural stress–strain profiles of neat epoxy, moringa/epoxy and moringa/bamboo/epoxy composites linear curves until failure indicating brittle mode while bamboo/epoxy composites shows non‐linear stress–strain profiles revealing non‐brittle mode of failure. Flexural properties exhibited by bamboo/epoxy and moringa/bamboo/epoxy reveal comparable properties to each other yet superior than moringa/epoxy and neat epoxy composites mainly attributed to the good bonding of constituents and compatibility. All the woven composites reveal an increase in flexural modulus and strength and are in the range of 31%–96% and 5.79%–51.12%, higher than the neat epoxy. Finally, fractured surfaces of specimens are analyzed using scanning electron microscope to understand the structure property correlations.

Effect of fiber layer formation on mechanical and wear properties of natural fiber filled epoxy hybrid composites

Natural fiber-reinforced polymer matrix composites are gathering significance in future trend applications such as automotive, aerospace, sport, and other engineering applications due to their superior enhanced mechanical, wear, and thermal properties. Compared to synthetic fiber, natural fiber is low adhesive and flexural strength properties. The research aims to synthesize the epoxy hybrid composites by utilizing the silane (pH = 4) treated Kenaf (KF) and sisal fiber (SF) as layering by uni, bi, and multi-unidirectional via hand layup techniques. Thirteen composite samples have been prepared by three-layer formation adopted with different weight ratios of E/KF/SF such as 100E/0KF/0SF, 70E/30KF/0SF, 70E/0KF/30SF, 70E/20KF/10SF, and 70E/10KF/20SF respectively. The effect of layer formation on the tensile, flexural, and impact strength of composites is studied by ASTM D638, D790, and D256 standards. The unidirectional fiber layer formed (sample 5) 70E/10KF/20SF composite is found maximum tensile and flexural strength of 57.9 ± 1.2 MPa and 78.65 ± 1.8 MPa. This composite is subjected to wear studies by pin-on-disc wear apparatus configured with a hardened grey cast-iron plate under an applied load of 10, 20, 30, and 40 N at different sliding velocities of 0.1, 0.3, 0.5, and 0.7 m/s. The wear rate of the sample progressively increases with increasing load and sliding speed of the composite. The minimum wear rate of 0.012 mg/min (sample 4) is found on 7.6 N frictional force at 0.1 m/s sliding speed. Moreover, sample 4 at a high velocity of 0.7 m/s with a low load (10 N) shows a wear rate of 0.034 mg/min. The wear-worn surface is examined and found adhesive and abrasive wear on a high frictional force of 18.54 N at 0.7 m/s. The enhanced mechanical and wear behavior of sample 5 is recommended for automotive seat frame applications.

Flexural behavior of carbon/glass inter-ply hybrid FRP composites under elevated temperature environments

Abstract In this research work, the three-point flexural performance of carbon and/or glass inter-ply hybrid epoxy composite by altering the hybrid ratio and stacking position was studied. These materials were tested at various temperatures (30 °C, 50 °C, 70 °C and 110 °C). The test results of hybrid composites results were compared with neat glass/epoxy and carbon/epoxy composites. The stacking position of carbon fibers in hybrid composite plays a vital role while doing a flexural test. Incorporation of two stiffer carbon fibers in glass/epoxy composite i.e., C2G3 and C1G3C1, resulted in a remarkable increment in the case of flexural strength. All composites exhibited ductile behavior at 110 °C. The fractured surfaces revealed the failure mechanism of the composites.

Study on the physical, mechanical, and thermal behaviour of RHN blend epoxy hybrid composites reinforced by Borassus flabellifer L. fibers

Study on the physical, mechanical, and thermal behaviour of RHN blend epoxy hybrid composites reinforced by Borassus flabellifer L. fibers

Three‐point bending fatigue behavior of basalt‐carbon‐glass/epoxy hybrid composites under saltwater environment

AbstractFatigue is a sudden failure of components below the maximum strength of the material when subjected to repeated loading. This paper studies the fatigue behavior of basalt, carbon, and glass fibers/epoxy hybrid composites under three‐point flexural loading and a saltwater environment. Five different composite panels were manufactured using the VARTM. The samples were then immersed in a saltwater solution for 60, 120, and 180 days before conducting the tests. Three‐point static and fatigue tests were conducted using UTM as per ASTM D7264‐07 and ASTM D7774‐12. The S‐N and stiffness degradation curves were plotted, and the morphology of the fatigue samples was investigated using SEM. In addition, the ion penetration in the solution was detected with ICP‐OES analysis. The result shows that bending fatigue properties of all composite samples show a degradation as the immersion period increases. This might be due to micro‐hole formation as the ions move from the sample to the saltwater solution.

Effect of Al2O3 and SiC Nano-Fillers on the Mechanical Properties of Carbon Fiber-Reinforced Epoxy Hybrid Composites

Polymeric nanocomposites are an emerging research topic, as they improve fiber-reinforced composites’ thermo-mechanical and tribological properties. Nanomaterials improve electrical and thermal conductivity and provide excellent wear and friction resistance to the polymer matrix material. In this research work, a systematic study was carried out to examine the tensile and hardness properties of a carbon fiber epoxy composite comprising nano-sized Al2O3 and SiC fillers. The study confirms that adding nano-fillers produces superior tensile and hardness properties for carbon fiber-reinforced polymer composites. The amount of filler loading ranged from 1, 1.5, 1.75, and 2% by weight of the resin for Al2O3 and 1, 1.25, 1.5, and 2% for SiC fillers. The maximum tensile strength gain of 29.54% and modulus gain of 2.42% were noted for Al2O3 filled composite at 1.75 wt.% filler loading. Likewise, enhanced strength gain of 25.75% and 1.17% in modulus gain was obtained for SiC-filled composite at 1.25 wt.% filler loading, respectively. The hardness property of nano-filled composites improved with a hardness number of 47 for nano-Al2O3 and 43 for nano-SiC, respectively, at the same filler loading.

Dry-sliding wear analysis and prediction using response surface method and fuzzy logic for Kota stone dust–fly ash–epoxy hybrid composites

This paper reports on the utilization of waste Kota stone dust and fly ash as filler materials in polymeric resin for the development of a new class of hybrid composite. Epoxy is taken as polymeric resin for the fabrication of different sets of hybrid composites. The fabricated samples are tested for their physical, mechanical, and dry-sliding wear properties. An experimental investigation shows the density, void contents, and water absorption rate increase as a linear function of fillers content. Mechanical testing is performed to evaluate the tensile, compressive, flexural, and hardness properties. From the experimentation, it is observed that the mechanical properties under investigation improve with the addition of either of the fillers. The maximum tensile strength obtained is 33.6 MPa, whereas flexural strength increases to 63.96 MPa resulting in an appreciable improvement. The compressive strength improves to 102.39 MPa and hardness reaches a Shore D number of 84. Sliding wear tests are performed as per the L16array based on the response surface method (RSM) using pin-on-disk apparatus. It has been observed that filler content, sliding velocity, sliding distance, and normal load in the declining sequence are significant in affecting the wear rate. Furthermore, the wear rate of composites is predicted with the help of response surface method and fuzzy logic within the experimental domain, and the results are compared with the outcomes reported in some of the existing literature. The study of worn composite surfaces using a scanning electron microscope resulted that the formation of wear tracks, grooves, craters, cavities, wear debris, etc. are some of the dominant mechanisms causing wear loss. As a result of our research, gainful utilization of wastes like Kota stone dust and fly ash for preparing polymer composites has opened up.

Carbon‐glass reinforced epoxy hybrid composites for crashworthy structural applications

AbstractThe goal of this work is to experimentally explore the crashworthiness performance and the deformation history of hybrid thin‐walled composite tubes. Glass (G)/carbon (C) reinforced epoxy circular specimens were prepared by wet wrap using hand lay‐up technique and then subjected to quasi‐static axial compressive loads to examine the impact of the hybridization process and stacking sequences on the crashworthiness performance and the deformation history. Crush indicators, that is, the initial peak force (), absorbed energy (AE), specific absorbed energy (SEA) of the designed tubes were assessed. The specimen's failure modes were discussed. Cost analysis for the proposed materials was carried out. According to the experimental findings, the hybridization and stacking order significantly influence the crashworthiness performance and failure mode of G/C reinforced epoxy composite tubes. C/2G/2C/2G/C hybrid is recommended as an energy absorber material for automobiles.

Mechanical characterization of E-glass fiber/aluminium powder filled with and without coconut fiber reinforced epoxy hybrid composite

In recent years, hybrid composites have played an important role in automobiles and aircraft applications. Coconut and peanut are the most used natural fillers due to their advantages such as easy availability, low density, low production costs, and good mechanical properties. Composites are prepared using epoxy resin, high-quality aluminium micro particle, E-glass fiber and coconut coir. Aluminium powder and epoxy resin at constant load 4.0 wt% and 82.0 wt%, which is in added with E-glass fiber: 8.0 wt% and coconut coir: 6.0 wt% (EAECC). Another composite compromising of 4.0 wt% Al, E-glass 14.0 wt% (EAE) was also fabricated and their properties are compared. Experimental research demonstrated the epoxy hybrid polymer composite without coconut coir inclusion remarkably has superior the mechanical properties more than 20% as compared with EAECC composite. Without the addition of coconut coir, considerable improvements in impact, flexural, compressive and tensile characteristics were made (97.2 J/m2, 144 MPa, 101 MPa and 94 MPa). There is a marginal difference in hardness with and without coconut inclusion in hybrid composite.

Analysis of the Effect of Hybridization of Coconut Shell Particles on Kenaf-Coir Based Epoxy Hybrid Composites

These days manufacturing and automobile industries need structures and materials that are good in strength, higher in toughness, low in weight as well as, are more sustainable in comparison to the presently used materials. Innovative materials like hybrid composite materials are gaining a lot of attention in industrial sector. Recent research work depicts that fiber-reinforced hybrid composite can be utilized in several application areas due to their good mechanical and physical characteristics like, high strength, low weight, and higher opposition to corrosion. In this paper, the combined effect of kenaf fibers and coconut shell nanoparticles on coir fibre reinforced epoxy composites has been investigated. Three different combinations of samples with varying content of coconut shell particles as 0, 3, 5 wt% respectively and kenaf fibres as 5, 4, 0 wt% respectively, along with coconut fibers and epoxy matrix, have been used in the research. Results have been calculated for the three samples using six different analytical models. The results are analyzed using Representative Volume Element (RVE) analysis. The mechanical characteristics like Poisson’s ratio, transverse modulus, longitudinal modulus, are evaluated. The outcomes of analytical modelling are in harmony with the results obtained from the RVE analysis. The outcomes of the research show that the hybridization of various fibres in the composite is among the most potent ways to augment the attributes of composite laminates. The incorporation of coconut shell nanoparticles has also seen to increase the elastic properties of the coir kenaf epoxy hybrid nanocomposite.

Effect of stacking sequence on abrasive wear behavior of abaca natural fiber reinforced polymer composites hybridized with glass fiber

This paper aims to investigate the tribological behavior of Abaca/Glass fiber reinforced epoxy hybrid composite. Different stacking sequences of Abaca(A) and Glass(G) fiber (AAAA, AGAG, AGGA, GAAG) are reinforced with epoxy polymer for fabrication of hybrid composite structure. Dry sliding abrasive wear characteristics of developed composites is analyzed by pin-on-disc (ASTM G99) test rig. The experiment is operated with different sliding velocities (1, 2, 3 m/s), applied load (10, 20, 30 N) and sliding distance of 2000 m. The experimental result indicates abrasive wear resistance is drastically enhanced with the abaca and glass fiber reinforcement in epoxy composite. Furthermore, least wear is found for AGGA hybrid composite. Morphology of worn surfaces were investigated by SEM analysis that indicates formation of micro crater, micro grooves and micro cracks.

Effect of bio-fibers and inorganic fillers reinforcement on mechanical and thermal characteristics on carbon-kevlar-basalt-innegra fiber bio/ synthetic epoxy hybrid composites

The hybridization of plant cellulose fillers in polymeric laminates is applied in different applications because of several benefits. The present investigation deals with the fabrication of four other eight-layer laminates by reinforcing bio fillers (coir, sisal, and hemp), Titanium carbide (TiC) nanoparticles, and ranging the stacking sequence of synthetic fabrics (carbon, Kevlar, Basalt, and Innegra) with bio/synthetic epoxy from wet layup technique. The fabricated laminate's characteristics were appraised by examining density, porosity, water absorption, flexural, impact strength, shore hardness, and thermal stability. It was observed from the experimental outcomes that the 3F8LTSE (Sisal, hemp, coir fillers, 2 layers of Carbon, Kevlar, Basalt, Innegra fabrics, and Titanium carbide reinforced synthetic epoxy) composite exhibited higher mechanical characteristics with a higher flexural strength (312.58 MPa), impact strength (35.13 kJ/m2), and shore D hardness (84.95), and decreased water absorption capacity by justifying its adequate for lightweight structures. The scanning electron microscope displayed the fiber pull out, debonding, and dispersion of fillers within the matrix of the composite. The current study also evaluates the prediction and performance of the artificial neural network (ANN) to model the physical, mechanical and thermal characteristics of bio/synthetic epoxy hybrid composites. However, the ANN model was more precise and proved that it is a primary method to optimize the properties of the fabricated bio/synthetic epoxy laminate.

Impact and post-impact flexural property of 3D five-directional braided carbon/glass hybrid epoxy composites

The impact property and residual flexural property of three-dimensional (3D) five-directional braided carbon/glass hybrid epoxy composites were studied. Four kinds of arrangement for carbon fiber and glass fiber in the axial yarn were designed. Taking pure carbon fiber composites (C/Ca) as the control, the rest of arrangements were that glass fiber and carbon fiber alternately arranged at the width direction (C/G1), glass fiber and carbon fiber alternately arranged at the thickness direction (C/G2), and only glass fiber appeared at the axial yarn (C/G3). Results showed that the C/G2 composite has higher impact energy absorption capacity, and the C/G1 composite has higher impact stress. The flexural properties of C/Ca composite are the best and that of C/G3 composite are the worst before impacting. This study is helpful for the structural design of composites in specific occasions.

Effect of silane-treated chitosan carbohydrate polymer and tanned leather/areca fiber hybrid epoxy composites on mechanical, drop load, and fatigue properties

Effect of silane-treated chitosan carbohydrate polymer and tanned leather/areca fiber hybrid epoxy composites on mechanical, drop load, and fatigue properties

Mechanical properties of waste natural fibers/fillers reinforced epoxy hybrid composites for automotive applications

Mechanical properties of waste natural fibers/fillers reinforced epoxy hybrid composites for automotive applications

Jute-basalt reinforced epoxy hybrid composites for lightweight structural automotive applications

The utilization of lightweight construction is one of the keys to increase the fuel efficiency and reduce the environmental effect of automobiles. Natural fiber composites are replacing expensive synthetic fibers increasingly commonly in the automotive sector. To further lower the weight and price of the vehicle without losing rigidity and strength, basalt (B) fiber could be incorporated into jute (J) fiber composites. For the generation of hybrid composite laminates, woven textiles made of J-fiber and B-fiber were combined with an epoxy matrix. The primary mechanical features of the J-B/epoxy composite laminates, including tensile, bending, shear, and bearing characteristics, were investigated. Hand lay-up approach was used to prepare the hybrid composite laminates. The impact of the number of J-plies relative to the number of B-plies on the mechanical properties was explored. The findings proved that the basalt/epoxy composite has the maximum ultimate tensile strength, young’s modulus, toughness modulus, bending strength, bending modulus, in-plane shear strength, and bearing strength. Whereas the J/epoxy composite showed the maximum failure strain and bending strain. Hybridizing J-fiber with B-fiber improved the tensile, bending, in-plane shear, and bearing characteristics of the prepared composite. The maximum specific tensile, bending, in-plane shear, and bearing strengths are displayed by 3B-2 J-3B, followed by 2B-4 J-2B.

Physical and Mechanical Properties of Bamboo Fiber/Glass Fiber Mesh Reinforced Epoxy Resin Hybrid Composites: Effect of Fiber Stacking Sequence

ABSTRACT To further improve the preparation efficiency and properties of bamboo fiber reinforced polymer composites (BFRPs) fabricated by the vacuum-assisted resin transfer molding (VARTM) process. Here, the bamboo fiber/glass fiber mesh reinforced polymer hybrid composites (BGRPs) were fabricated by VARTM to determine the effects of three fiber stacking sequences (namely, GBBGBBG, BGBGBGB, and BBGGGBB; B: bamboo fiber, G: glass fiber mesh) on the physical and mechanical properties, as well as void characteristics of BGRPs (i.e. BGRP-1, BGRP-2, and BGRP-3). The results showed that the incorporation of glass fiber meshes could shorten the injection time of epoxy resin and improve the mechanical properties of BFRPs. BGRP-1 exhibited the lowest water absorption (1.31%) and the highest shear strength (15.55 MPa). Glass fiber meshes on the surface and bottom of BGRP-1, respectively, served as buffer layers to retard mechanical damage, so that BGRP-1 had the best drop hammer impact properties. BGRP-2 represented the highest flexural strength and flexural modulus of 92.22 MPa and 6.69 GPa, respectively. The mechanical properties of BGRP-3 were inferior to those of BGRP-1 and BGRP-2, and more voids were observed in the middle of BGRP-3 in micro-CT slices induced by inadequate epoxy resin impregnation on bamboo fibers.