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The composite material is made of different materials. It retains the advantages of the original material and reflects combined characteristics of all the constituents. Polymer matrix composites are popular in the recent industrial applications. Friction and wear governs the tribological aspects of polymer composites. This paper revel the experimental study of friction and wears behavior of epoxy composites filled with bronze and graphite fillers as per ASTM standards. Three compositions were studied and it was found that composition ‘A’ has lowest coefficient of friction (0.281) whereas composition ‘C’ has highest coefficient of friction (0.325). The composition ‘A’ has lowest wear rate of 0.5 μm/s and composition ‘C’ showed highest wear rate of 3.25 μm/s. Use of graphite and bronze along with epoxy exhibited formation of lubricating layer and enhanced friction and wear behavior of the composites.

The chemical precipitation was used to obtain carbon fibers (CF) with surface modified by magnetite particles (Fe3O4). Processing was carried out by employing up to three subsequent coating stages ...

This work is intended to explore the influence of barite particulate filler on the mechanical behaviour of carbon fiber (Cf) reinforced polymer matrix (CFRP) composites. The carbon fiber utilized for the study was T300 grade and the polymer matrix utilized was LY556 epoxy resin (Epr). The CFRP composites prepared with 55 weight (wt.) % T300 carbon fiber and 45 wt.% LY556 epoxy resin without barite particulate filler was utilized for control experimentation. The CFRP composites with barite filler were prepared by varying the proportion of barite particles from 2.5 wt.% to 15 wt.% in steps of 2.5 wt.%. The composites were prepared using the hand lay-up process and the barite particles were mixed with the epoxy resin by means of ultrasonic agitation. The prepared composites were subjected to tension, compression, hardness, flexural and impact testing. The CFRP composites with 10 wt.% barite particles yielded the best tensile strength, hardness and impact strength. The tensile strength, hardness and impact strength attained an increase of 13.18%, 5.6% and 18.68% respectively, compared to the CFRP composite without barite filler. The compressive strength of the CFRP composite with 15 wt.% barite filler was observed to be more than twice the compressive strength of the CFRP composite without barite filler. However, the flexure strength reduced steadily with the addition of barite particulates. The fractured surface morphologies of the prepared composites were characterised using the Scanning Electron Microscope (SEM). The chemical composition and morphology of barite powder was analysed using Energy Dispersive X-Ray Spectroscopy (EDX) and SEM, respectively.

In this work, the object of study is an epoxy nanocomposite based on TiO2 nanoparticles and epoxy resin, and the subject is the preparation and physical and mechanical properties of TiO2/epoxy nanocomposites. The characteristics of the properties and methods of synthesis of the initial components for the synthesis of epoxy nanocomposites - epoxy resins and nanoparticles of titanium dioxide are given, and data on epoxy nanocomposites based on nanoparticles of titanium dioxide are presented. It was found that the addition of TiO2 to the epoxy matrix reduces the coefficient of friction and significantly increases the wear resistance of such nanocomposites.

The growing environmental awareness in the last few decades has driven the research and development of composites reinforced with natural fibers as an alternative to replace synthetic fiber composi...

Spent coffee grounds (SCGs) represent a huge amount of global waste whose post-use disposal triggers environmental issues. In this study, SCGs were successfully treated and modified to improve the mechanical properties of biobased composites with epoxy matrix. A two-step treatment was proposed, pretreating by a NaOH solution and modifying by maleic anhydride (MA). MA acts as a coupling agent to create the internal network in composite through the interaction between functional groups. Accordingly, MA improves the interface between phases in composite, ensures a better physical property compared to the composite without modification. Consistently, the two-step treatment depicts improved mechanical properties: flexural modulus and flexural strength increased to 3053 MPa and 45 MPa, respectively, compared to 2429 MPa and 33 MPa for composite with pure SCGs.

The present study examined the effects of drilling parameters such as spindle speed (N), feed rate (f), diameter of the tools (d) and drill geometry such as twist drills (HSS-TiN) and brad & spur drills (BSD) used on delamination damage in a biosandwich structure consisting of an epoxy matrix reinforced with bidirectional jute fibres and cork (JFCE). Response surface methodology (RSM) and artificial neural networks (ANNs) were exploited to evaluate the influence and interaction of the cutting parameters on the delamination factor (Fd) at the output during drilling. In addition, several optimization methods, such as desirability-based RSM, the genetic algorithm (GA) and the fmincon function, were applied to validate the optimal combination of cutting parameters (f, N and d) in the structures studied in biosandwiches during this research. According to the experimental results, severe damage was indeed observed with the BSD tool (Fd = 1.684) compared to the HSS-TiN tool (Fd = 1.555) for the same cutting conditions. To obtain the minimum Fd, the optimum conditions obtained by GA were respectively 1397.54 rev/min, 51.162 mm/min and 5.981 mm for HSS-TiN for f, N and d.

This article presents the mechanical, physical, and tribological properties of the boron carbide (B4C) reinforced epoxy matrix composites (BEMCs). The BEMC samples were prepared with various B4C concentration of 0%, 1%, 2%, 3%, and 5%. B4C particles were treated with a silane coupling agent to ensure efficient adhesion with epoxy. The influence of a range of parameters (particle loading, sliding speed, sliding distance, and normal load) on the wear and friction behavior of BEMCs were evaluated by conducting wear tests under dry sliding conditions on a pin-on-disc wear test set-up. The addition of B4C to the epoxy polymer improved the wear resistance of the composites. Maximum wear resistance and coefficient of friction were observed for the composite with the highest percentage of B4C (5%). The specific wear rate was reduced on increasing load and sliding distance and increased with the sliding velocity. Mechanical properties including compression strength, flexural strength, and impact energy, along with physical properties such as density and hardness, were also evaluated. B4C particles improved the hardness, density, flexural and compression strength, and impact resistance of the composites. Scanning electron microscope (SEM) analysis of the worn-out surfaces and flexural fractured surfaces was carried out to predict the possible wear and fracture mechanisms. Micro-ploughing, abrasion, and adhesion were the wear mechanisms in BEMCs. Under the flexural loads, particulate de-bonding, pull-out, and brittle fracture of the matrix were the governing failure mechanisms.

In this research work, chopped neem fibre and woven banyan fibre were stacked into seven different sequences and fabricated by the hand lay-up technique. The laminates consist of 70% epoxy matrix, ...

In this work, the influence of silane treatment on characterization of Ipomoea staphylina plant fiber composites reinforced with epoxy matrix are studied. The silane treated I. staphylina fiber rei...

Glass-fiber reinforced polymer (GFRP) composite rods with epoxy matrix filled with electrically nonconducting particles find widespread use in high-voltage electrical insulator applications. The service loads require a range of different, minimum material property values, e.g. toughness, tensile, or compressive strength, but also component-specific performance, e.g. pull-out friction of surface crimped metal fittings or electric breakdown strength. The contribution discusses selected examples of the effects of different particle filler types on the properties of filled epoxy resin as well as on the behavior of GFRP rods with such a matrix. In all investigated systems CaCO3 was used as micron-sized filler, complemented by different amounts of either nanosilica or core-shell rubber (binary filler), or by both, nanosilica and core-shell rubber (ternary filler). With ternary filler combinations at a content of 36 wt%, fracture toughness GIC was improved in nanocomposite epoxy plates and in GFRP rods by 60% and 100%, respectively compared to a matrix with 20 wt% CaCO3 (used as reference system). The glass transition temperature Tg for some ternary systems dropped from 160 °C (for neat epoxy), to approximately 140 °C, the maximum allowed drop in Tg in view of requirements from further processing steps of the electrically insulating components. The ternary fillers yield transfer of the improvements of fracture properties from epoxy nanocomposite plates into the GFRP rods beyond that of the system with CaCO3 filler only. Compressive strength of the GFRP rods was improved by about 20% only for the binary nanosilica and CaCO3 filler, and was not significantly enhanced with the ternary systems. That combination, however, did not yield improvements in toughness beyond the CaCO3-filled nanocomposite plates and rods. With the range of filler types and contents investigated here, it was hence not possible to simultaneously optimize both, fracture toughness and compressive strength of the GFRP insulator rods.

The present work focus on identifying tensile & flexural characteristics of Boron Carbide (B4C) filled E-Glass/Epoxy composite with and without application of low temperature. A reinforcement of E-glass is provided to Epoxy matrix for composite fabrication. Hand lay-up technique is adopted for fabricating two batches of test specimens and one batch is treated to -60°C temperature treatment. One batch of specimens involves E-glass/Epoxy composite without B4C, 5% & 10% B4C tested at ambient temperature. Additional batch are fabricated with said composition, treated to -60°C for 1 hour duration, later tested according to ASTM D3039 and D790. The experiment reveals the improvement in the said properties of composite material after the addition of B4C. Additionally implementation of low temperature treatment improves tensile and flexural properties of test specimens. These will depict the improved characteristics of composites with the said conditions due to addition of strong filler materials B4C, thermal contraction of fibres post low temperature treatment.

The primary focus of this research work is to develop epoxy based composite structure dispersed with B4C and aluminium metallic particles in order to facilitate the material to behave with enhanced stability when subjected to mechanical environment. An attempt was made with as-received B4C metallic particles and B4C augmented with Al particles as reinforcements with epoxy matrix and samples were fabricated through mechanical mixing followed by ultrasonic mixing in order ensure thorough mixing of the metallic additives. The as prepared samples were characterized for optical, mechanical and thermo-mechanical properties for ensuring the usefulness for the mechanical applications. The results of the same are tabulated and discussed which exclusively show the enhancement in the behavior of the structure positively when B4C is augmented with 5% Al particles. Further the results are comprehensively reported in this article.

In the present work, two types of composites were produced, both reinforced with 30 vol% of curaua fibers (CF). In the first type, only the fiber was functionalized with graphene oxide (GO), producing the GOCF/EM composite. While in the second, only the epoxy matrix (EM) was functionalized, producing the CF/GOEM composite. The objective of the work was to investigate the influence of functionalization with GO on the tensile properties of these produced composites. In comparison with the non GO-functionalized composite, as control CF/EM, the results revealed an increase in yield strength (64%), tensile strength (40%), Young's modulus (60%) and toughness (28%) of the CF/GOEM composite. The GOCF/EM composites for which the fibers were functionalized with GO also performed better than the CF/EM composite. The ANOVA and Tukey tests confirm this increase. As for ductility, within the standard deviation, no change was observed between samples functionalized by GO and those from the control. For the first time, comparing the results of the composites, it was demonstrated that a polymer matrix functionalized by GO offers superior tensile performance compared to the other types, keeping the same GO concentration in the composite. This fact is corroborated by the analysis of the corresponding fracture mechanisms. Preliminary results of composite with simultaneous functionalization of both fiber and epoxy matrix failed to present superior properties. This might be attributed to high amount of GO, which is apparently not a good reinforcement as the curaua fiber.

Like most macromolecule polymers, epoxy resin (EP) is easy to burn, and there are great fire safety hazards in the process of use. Therefore, how to improve the fire safety of EP becomes one of the...

In this comprehensive investigation, we evaluate the mechanical properties and the effect of drilling parameters (spindle speed, 355, 710 and 1400 rev/min; feed rate, 50, 108 and 190 mm/min; and the tool diameter, 5, 7 and 10 mm) as a function of the cutting process on the delamination factor when drilling jute fabrics reinforced epoxy matrix biocomposites. The study is carried out using different drill geometries and material (HSS_TiN, HSS and brad and spur drill bits). The design of experiment is developed by the application analysis of variance (ANOVA). The response surface methodology (RSM) and artificial neural networks (ANN) are applied to validate the results obtained during the experiment and to predict the behaviour of the structure under any cutting condition. Result analysis showed the superiority of the ANN model over the RSM model, while the feed rate had a significant contribution on spindle speed and diameter. The optimum conditions obtained for the Fd factor were a feed rate of 51 mm/min, a spindle speed of 1160 rev/min and a drilling diameter of 5 mm.

The purpose of this present research work is to assess the static and dynamic mechanical properties of an eco-friendly natural cellulosic fiber (Phoenix sp.) reinforced epoxy composites. The cellulosic fiber was isolated from Phoenix sp. plant petioles, and it was treated with various concentrations of sodium hydroxide (5, 10, 15 and 20%) solution. The impact of treatments on tensile, flexural, impact and dynamic mechanical properties of the fabricated composite was explored and optimized. Moreover, the mechanically tested samples were subjected to morphological analysis to predict the failure mechanisms. The outcomes revealed that the treated fibers had good interfacial bonding with epoxy matrix (confirmed through morphological and single fiber pull-out studies), reduced the failure mechanisms (fiber pull-outs and fiber debonding) and exhibited good static and dynamic mechanical properties of composite materials than untreated fiber composites. It is concluded that composites fabricated using 15% of sodium hydroxide treated fiber could be used to manufacture automotive panels and other lightweight industrial products.

Fiber-reinforced polymer composite laminate is weak in the Z-direction, which limits its application. Herein, short carbon fiber (SCF) was decorated with graphene oxide (GO) to form GO@SCF, which was used to improve epoxy matrix and thereby the interlaminar shear strength (ILSS) of carbon fiber fabric (CFF)-reinforced epoxy composites. The effect of GO@SCF on the ILSS of the composite has been examined. It showed that the optimal content of GO@SCF was 0.1 wt%, and the maximum value of ILSS reached 59.4 MPa, which was 14.7% higher than the pure CFF/epoxy composite. The neat SCF was also employed to enhance the ILSS for the purpose of comparison. The results indicate that GO@SCF has better effect on reinforcing the ILSS than the neat SCF. This study provides an effective approach for the reinforcement of the ILSS of CFF-reinforced epoxy composites.

An organic/inorganic hybrid nanocomposite material was fabricated by blending epoxy resin with hydroxyl-terminated polybutadiene-based quaternary ammonium salt (HTPB-QAS) intercalated montmorilloni...

In recent times, there is a growing demand for low-cost raw materials, renewable resources, and eco-friendly end products. Natural fibers are considered as strong candidates to be used as a potential reinforcement for composite manufacturing. In the current study, natural fibers extracted from banana peel were coated with bacterial cellulose through a green biosynthesis approach as well as by a simple slurry dipping method. Thus, natural fibers from banana peel waste were used the first time, to produce bacterial cellulose-natural fiber composites. SEM analysis revealed good interaction between the hybrid fibers and the epoxy matrix. Thermal gravimetric analysis results revealed that the degradation temperature increases because of the addition of bacterial cellulose on fiber surface, which improves the thermal stability. The maximum thermal decomposition temperature (405°C) was noticed for nanocomposites reinforced by banana fibers with bacterial cellulose deposited on their surface. Whereas the lowest weight loss was also found for the same sample group. The highest tensile strength (57.95 MPa) was found for SBC-BP/epoxy, followed by DBC-BP/epoxy (54.73 MPa) and NBP/epoxy (45.32 MPa) composites, respectively. Composites reinforced by both types of hybrid banana fibers shown comparatively higher tensile performance as compared with the neat banana peel fiber-epoxy composites, which can be attributed to the high strength and stiffness associated with the bacterial cellulose. Overall, this study suggests a successful and green route for the fabrication of natural fiber-reinforced composites with improved properties such as tensile strength and thermal stability.

In the present study, the milled carbon fiber (MCF) and conductive polyaniline (PANI) are impregnated in the epoxy matrix to synthesize lightweight nanocomposite providing efficient microwave absor...

An effect of boron nitride nanotubes (BNNTs) with a low concentration on the ablative resistance of the epoxy matrix was evaluated. A linear ablation rate of a 0.3 wt% BNNT/epoxy composite was nota...

The perspectives of using new modified polymer-based materials for the restoration of vehicle parts are substantiated in this article. The use of binders based on epoxy diane oligomers is proved to be promising in the formation of anti-corrosion coatings. To improve the properties of epoxy matrices at the preliminary stage of their formation, active additives are introduced. The use of a phthalimide modifier, which contains functional groups active before interfacial interaction, is proved to be promising as well. An epoxy diane oligomer is selected as the binder‘s main component in the formation of composites. The hardener polyethylene polyamine is used for crosslinking the epoxy compositions. It allows to harden materials at room temperatures. The choice of a phthalimide modifier for the improvement of thermophysical properties of the developed materials is substanciated. Heat resistance (according to Martens), glass transition temperature and thermal coefficient of linear expansion of modified epoxy composites are studied. To form a composite material or protective coating with improved thermophysical properties, the modifier phthalimide in the amount of q = 0.25… 0.50 pts. wt. at q = 100 pts. wt. of epoxy oligomer ED-20 should be introduced into the epoxy binder. Based on the tests of thermophysical properties of phthalimide-modified materials, the allowable temperature limits, at which it is possible to use the developed composites, are found.

In this study, the effect of number of surface layers on the flexural behavior of carbon fiber surfaced 3D integrated woven spacer sandwich composite structures was investigated. The resin impregnated carbon fibers used as the bottom and top surface material were joined to the threedimensional intermediate fabric in 2, 3 and 4 layers using a vacuum infusion technique. Two different polymer materials, epoxy and polyester, were used as resin material. The composite sandwiches plates with different surface thicknesses and resin materials are cut into samples according to the standards. In order to test the flexural behavior, three point bending tests were performed at room temperature and the flexural force-displacement curves of the samples were established. The results showed that the sandwich composites increased their resistance to flexural with increasing number of surface layers. It has been found that epoxy matrix composites exhibit higher strength than polyesters and that the increase in strength due to layer thickness is greater.

Anisotropic viscoelastic behavior of high-performance unidirectional polymer-based hybrid composites (UPHCs) in which graphite fibers are embedded into the epoxy matrix enriched by carbon n...

Epoxy matrix composites owing to their outstanding properties such as high strength, low weight, high thermal stability and good stiffness are broadly utilized in various industries. Also, the basalt fibers as a green industrial material show various extraordinary properties such as high mechanical strength, desired stability, suitable chemical resistance, and high temperature resistance. In this study, the effect of silane-modified nanozirconia on the tensile and flexural properties of basalt fibers/epoxy composites is investigated. As a first step, the surface of nanozirconia was modified with a silane coupling agent namely 3-methoxysilyl propyl amine. Fourier transform infrared (FT-IR) spectroscopy has been used to demonstrate the chemical nature of the silanized ZrO2 nanoparticles prepared. 3-methoxy silyl propyl amine/nanozirconia with various loadings (0, 1, 3 and 5 wt.%) were added to the epoxy resin via mechanical and ultrasonication routes. The resultant mixtures were then utilized to fabricate ZrO2/satin texture basalt fibers/epoxy nanocomposites using hand-layup technique. This symptomatic behavior exposes the successful modified ZrO2 nanoparticles to enhance the interfacial bonding. Also, a scanning electron microscope (SEM) was used to study the distribution level of silanized ZrO2 nanoparticles in the matrix as well as the fracture surfaces of the specimens. Experimental results from three-point bending and tensile tests showed that with the dispersion of 3 wt.% nanozirconia, flexural strength, flexural modulus, flexural failure strain, tensile strength, tensile modulus and tensile failure strain enhanced by 90, 74, 84, 76, 85 and 14%, respectively, compared with specimens without nanozirconia. The SEM observations of the fracture surfaces of the nanocomposites clearly indicated that the enhancement in the flexural and tensile properties was due to the improvement in the interfacial adhesion between the basalt fibers and modified ZrO2 nanoparticles-enhanced epoxy matrix.

Reinforcement of polymer matrices with natural lignocellulosic fibers (NLFs) is today presenting great potential for the reduction of both product weight and cost in many industrial sectors as well as the advantage of being renewable and eco-friendly materials. For some industrial applications, especially in ballistic armor, the materials are expected to meet technical and mechanical requirements in terms of impact behavior, which motivate the present work. This work conducted a notch toughness assessment by Izod and Charpy impact tests of epoxy matrix composites reinforced with different volume fractions of fique fabric, up to 50 vol%. Statistical analyses indicated significant differences between composites with distinct amount of fique fabric. Failure mechanisms were analyzed by scanning electron microscopy (SEM). The results revealed that composite reinforced with 40 vol% of fique fabric presented the best notch toughness performance. Composites with 15 and 30 vol% of fique fabric display predominantly brittle fracture associated with lower impact energies. With higher amount, 50 vol%, of fique fabric reinforcement both Izod and Charpy impact energy suffered a small decrease according to the Roger and Plumtree model. Keywords: Fique fabric, Impact tests, Epoxy matrix, Natural fiber composite

With the aim to prepare adhesives and anticorrosion coatings based on ED-20 epoxy resin, polyvinylformalethylal (viniflex) and ZnO nanoparticles were used as modifiers, whereas aromatic amine hardener (diethyltoluenediamine) was employed as a structure-forming agent. Technology of addition of nanofiller to the modified epoxy matrix was developed and physicomechanical characteristics of binders were determined. It was revealed that filling of the ED-20 resin modified with viniflex with ZnO nanoparticles provides anticorrosion coatings on the steel surface and decreases residual stresses of the binders. Physicomechanical characteristics of the products of modification were determined by dynamic mechanical analysis.

The static and fatigue tensile properties of high-strength polyacrylonitrile (PAN)-based carbon (IMS60) and electronic (E)-class glass (E-glass) hybrid fiber-reinforced epoxy matrix composites (HFRPs) were investigated. The fiber orientations of the HFRP specimens were set to unidirectional with [(0(IMS60))/(0(E−glass))]S (subscript S means symmetry and [(0(IMS60))/(0(E−glass))/(0(E−glass))/(0(IMS60))]), [(0(E−glass))/(0(IMS60))]S, [(0(E−glass))/(0(IMS60))2]S, [(0(E−glass))/(0(IMS60))3]S, [(0(E−glass))/(0(IMS60))5]S, [(0(E−glass))2/(0(IMS60))]S, [(0(E−glass))3/(0(IMS60))]S, and [(0(E−glass))5/(0(IMS60))]S. Under static loading for the [(0(IMS60))/(0(E−glass))]S, [(0(E−glass))/(0(IMS60))]S, [(0(E−glass))/(0(IMS60))2]S, [(0(E−glass))/(0(IMS60))3]S, and [(0(E−glass))/(0(IMS60))5]S HFRP specimens, the stress applied to the specimen was almost linearly proportional to the strain until failure. However, the tensile stress–strain curves of the [(0(E−glass))2/(0(IMS60))]S, [(0(E−glass))3/(0(IMS60))]S, and [(0(E−glass))5/(0(IMS60))]S HFRP specimens had a complicated shape (jagged trace). The Weibull statistical distributions of the tensile strength values were also examined. The Weibull moduli for the [(0(E−glass))/(0(IMS60))]S, [(0(E−glass))/(0(IMS60))2]S, [(0(E−glass))/(0(IMS60))3]S, [(0(E−glass))/(0(IMS60))5]S, [(0(E−glass))2/(0(IMS60))]S, [(0(E−glass))3/(0(IMS60))]S, and [(0(E−glass))5/(0(IMS60))]S HFRP specimens were higher than those for the mono carbon fiber-reinforced epoxy (CFRP) and glass fiber-reinforced epoxy (GFRP) specimens. Under fatigue loading, the fatigue properties of the HFRP specimens showed CFRP-dominant behaviour at high stress levels and GFRP-dominant behaviour at low stress levels. The fatigue properties of the HFRP specimens increased with increasing volume fraction of CFRP in the following order: ([(0(E−glass))/(0(IMS60))5]S > [(0(E−glass))/(0(IMS60))3]S > [(0(E−glass))/(0(IMS60))2]S > [(0(IMS60))/(0(E−glass))]S > [(0(E−glass))/(0(IMS60))]S > [(0(E−glass))2/(0(IMS60))]S > [(0(E−glass))3/(0(IMS60))]S > [(0(E−glass))5/(0(IMS60))]S).

A glassy hyperbranched polymer (HBPG) was synthesized and dispersed within an aeronautical graded epoxy matrix as toughening agent. This filler is a polyester characterized by a Tg higher then room temperature (∼90 °C) and obtained by means of bulk poly-condensation reaction starting from a diphenolic acid as precursor. HBPG/epoxy systems were prepared considering two concentration levels (0.1 and 5 wt%) and the effects on mechanical properties and fracture toughness were investigated. HBPG induces a limited reduction of the Tg along with an improvement of the fracture toughness performances as indicated by the increase KIC and GIC values.

The European steel industry produces about 70 million tons/year of steel by the electric arc furnace (EAF). The slag consists of about 15% by weight of the produced steel, thus from the perspective of the circular economy, it has a high potential as a co-product. This research aims to assess an innovative reuse of EAF slag as filler in different polymer matrixes: thermoplastic (polypropylene), thermosetting (epoxy resin), elastomeric (nitrile butadiene rubber), and recycled end of life rubber tire. A comparison between neat polymer and polymer filled with a certain amount of EAF slag has been carried out by tensile (or flexural), compression, and hardness tests. Experimental results show that slag as a filler increases the composites’ hardness and elastic modulus at the expense of toughness. For a safe reuse of the slag, the leaching of hazardous elements must comply with current legislation. It was found that, although the used EAF slag releases small amounts of Cr, Mo, and V, incorporating it into a polymer matrix reduces the leaching. The EAF slag particles distribution has been observed by scanning electron microscopy (SEM) images. The obtained results show good technical feasibility of this innovative slag application so that it could pave the way to a new industrial symbiosis between dissimilar sectors, bringing economic and environmental benefits.

The influence of the Ultem-1010 polyetherimide (PEI) on the physicomechanical properties of the ED-20 epoxy matrix and carbon-fiber-reinforced plastics (CFRP) based on the epoxy-polyetherimide binders is studied. It is shown that the introduction of PEI allows one to increase the impact strength and fracture toughness of the matrix 70 and 350%, respectively. The fracture toughness of the CFRP increases 40% with the rise in the PEI concentration. The correlation between the fracture toughness of the composites and their matrices has been established.

In this investigation, the specific heat of four fabric reinforced hybrid composite materials with filled stratified epoxy matrix was analysed. All hybrid composite materials were made of 17 layers, for which were used carbon, aramid, glass and hybrid fabrics. The stratified filled epoxy matrix of fabric reinforced hybrid composites represents a matrix, in whose structure it was used three types of fillers mixtures between certain plies. The investigation of specific heat of hybrid composite materials was performed by using of Differential Scanning Calorimetry instrument. It was analysed the effects of fiber orientation at various angles on specific heat of fabric reinforced hybrid composites with filled stratified epoxy matrix and the influence of fillers mixtures on these thermal properties of epoxy matrix. Also, it was studied the specific heat of hybrid epoxy composites in dependence of carbon and aramid plies number in studied materials structure.

In this study, mechanical properties of epoxy resin were enhanced using carbonized cow bone (CCB) particulates due to changes in its microstructure and reduction in polymer chains’ mobility. The CCB particles were dispersed in epoxy matrix at 40 wt%, 50 wt%, and 60 wt% concentrations for particles size of 150 μm, 300 μm, and 600 μm by mechanical stirring. Scanning electron microscope (SEM) was used in microstructural study of the CCB and the composites. This study was designed with taguchi in minitab software, and the responses of the mechanical properties were investigated based on interactions and effects of concentration and particles size on the properties. From the results obtained, the mechanical properties varied with particle size but were generally better between 40 and 50 wt% at 150 μm.

The current study focuses on the development of silanized graphene oxide reinforced basalt fiber/epoxy composites for enhanced tribological and viscoelastic properties. The modified-graphene oxide nanoplatelets were characterized using energy-dispersive X-ray spectroscopy, and Raman analyses. Pin-on-disk wear test and dynamic mechanical thermal analysis were conducted to determine the tribological and viscoelastic properties of the fabricated specimens with different silanized-graphene oxide loadings in the matrix (0–0.5 wt.% at a step of 0.1). The multiscale specimens were fabricated using the hand lay-up technique. The best silanized-graphene oxide loading for effectively enhancing the tribological properties was found to be 0.4 wt.%, whose wear rate and friction coefficient were 62% and 44%, respectively lower than those of the neat basalt/epoxy composite. The examination of the worn surfaces showed the enhanced basalt fiber/epoxy bonding in graphene oxide-reinforced specimen. From the results of dynamic mechanical thermal analysis, the specimen filled with 0.4 wt.% silanized-graphene oxide demonstrated the highest increase of 130% and 13.6℃ in the storage modulus and glass transition temperature as compared to the neat composite. This study indicated that the addition of silanized-graphene oxide considerably enhanced the tribological and viscoelastic properties of the fibrous composites.

Titanium aluminium carbide powder was reaction synthesized and used as reinforcement in the aircraft grade epoxy matrix (LY556) to develop a high-performance conductive polymer composite. The particle sizes of 4 and 7 µm were employed from 0 to 40 wt.% to improve the mechanical and electrical properties of conductive polymer composites. It was observed that the percolation characteristics were exhibited at a critical threshold of 20 wt.% for both the filler particle sizes. Further, microstructural observations revealed the formation of a conductive network in the conductive polymer composites when the filler content was 20 wt.%. The tensile and flexural properties were increased when the particle size was decreased. Experimental values were then compared with the available analytical models for validation. The mechanical and electrical properties of the conductive polymer composites were optimized by tailoring the filler particle size to 4 µm and particle loading at 20 wt.%. Compared to neat epoxy, the optimized conductive polymer composites have shown a simultaneous increase in strength, stiffness and conductivity performances, which can find applications in aerospace and electronics industries.

In this study, we propose a new approach for the homogeneous liquid-phase transfer of graphene oxide (GO) into epoxy resin. This makes the process more efficient, while achieving fully uniform distribution of GO flakes within the epoxy matrix. Introduction of as little as 0.4% and 0.6% GO drastically increases the viscosity of the compositions, pointing at the highly exfoliated condition of GO in the resin. A significant accelerating effect of GO on the curing reaction is attributed to reactive groups on the GO surface. The study of the thermo-mechanical properties revealed that the introduction of relatively small amount of GO (0.2 wt%) into the epoxy matrix results in the increase of the storage modulus by 25.4% (3035 MPa) relative to the neat epoxy polymer (2420 MPa). The use of the high-temperature curing agent affords the composites with significantly higher glass transition temperatures, compared to the low-temperature curing agent, broadening the scope of their potential applications.

This study aims to characterize and find the suitability of Calotropis procera fibers to reinforce polymer matrices from Fourier-transform infrared spectroscopy and X-ray diffraction studies. Compo...

The aim of this study was to investigate the influence of the matrix properties, number of the carbon and aramid layers and fiber orientation on low velocity impact behavior of the fabric reinforced hybrid composites with stratified filled epoxy matrix. The impact tests were performed with the drop weight impact system at 90.629 J of energy level. The damage areas were analyzed by the visual inspection and tomographic images. The results showed that the matrix properties have a great influence over the fracture mode of the hybrid composites, while the fault degree of the damaged areas depends on the fiber orientation. The highest impact resistance was obtained in the case of hybrid composites with 0° ply orientation.

This paper reports the development of Silicon carbide (SiC) epoxy composites and their Mechanical properties such as tensile strength, flexural strength, impact testing. Samples were prepared by different weight percentage of SiC with epoxy matrix .Morphology of the prepared composites was also done.

Natural fiber composites (NFC) have become very popular in the structural applications due to their bio-degradability and ease of availability. The major limitation with NFCs for the industrial applications is the poor strength to weight ratio and stiffness to weight ratio compared to the polymer matrix composites. In this paper an attempt is made to improve the mechanical performance of the NFC through hybridization. Jute and Banana fibers are amalgamated with epoxy matrix at different volume fractions and Hybrid natural fiber composite (HNFC) is prepared and characterized for tensile, flexural and hardness behavior. The results proven that the HNFC offered superior performance than pure Jute and Pure banana fiber composite.

Usually, a polymer composite with a viscoelastic response matrix has a creep behavior. To predict this phenomenon, a good knowledge of the properties and mechanical constants of the material becomes important. Schapery’s equation represents a basic relation to study the nonlinear viscoelastic creep behavior of composite reinforced with carbon fiber (matrix made by polyethrtethrtketone (PEEK) and epoxy resin). The finite element method (FEM) is a classic, well known and powerful tool to determine the overall engineering constants. The method is applied to a fiber one-directional composite for two different applications: carbon fibers T800 reinforcing an epoxy matrix Fibredux 6376C and carbon fibers of the type IM6 reinforcing a thermoplastic material APC2. More cases have been considered. The experimental results provide a validation of the proposed method and a good agreement between theoretical and experimental results.

Polymer blends is a well-established and suitable method to produced new polymeric materials as compared to synthesis of a new polymer. The combination of two different types of polymers will produce a new and unique material, which has the attribute of both polymers. The aim of this work is to analyze mechanical and morphological properties of bio-phenolic/epoxy polymer blends to find the best formulation for future study. Bio-phenolic/epoxy polymer blends were fabricated using the hand lay-up method at different loading of bio-phenolic (5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) in the epoxy matrix whereas neat bio-phenolic and epoxy samples were also fabricated for comparison. Results indicated that mechanical properties were improved for bio-phenolic/epoxy polymer blends compared to neat epoxy and phenolic. In addition, there is no sign of phase separation in polymer blends. The highest tensile, flexural, and impact strength was shown by P-20(biophenolic-20 wt% and Epoxy-80 wt%) whereas P-25 (biophenolic-25 wt% and Epoxy-75 wt%) has the highest tensile and flexural modulus. Based on the finding, it is concluded that P-20 shows better overall mechanical properties among the polymer blends. Based on this finding, the bio-phenolic/epoxy blend with 20 wt% will be used for further study on flax-reinforced bio-phenolic/epoxy polymer blends.

Composite material plays very significant role in number of field such as automotive, aerospace, defense, and in other challenging areas. This is because of their advanced physical, mechanical, chemical, and other properties. And nowadays lots of focus on research are in the field of hybrid composites. Hybrid composite offers better properties in comparison to normal composite. In this paper, tensile and compressive strengths of Kevlar fiber with epoxy matrix LY556 resin and the hybridization of Kevlar and E-glass with same epoxy matrix are done. Comparison shows the impact on both properties. Orientation of Kevlar and glass fiber is 0° and 90°. Sample used in testing is prepared according to the ASTM standards. Hybridization of Kevlar and E-glass composite is used to make components of wing box in aerospace industry, at the place of aluminum alloys.

International audience; Transparency is a crucial factor in developing functional and decorative thin films and coatings, but incorporation of nanoparticles into organic resins for improving their properties quite often makes them opaque. In this work, photophysical properties of epoxy/layered double hydroxide (LDH) nanocomposite coatings were correlated with the dispersion state of LDH in the epoxy resin. The quality of solid epoxy network was assessed in terms of the Cure Index (CI) in relation to the transparency of the films containing 0.1, 0.5, 0.7, 1.0, and 3.0 wt% Mg–Al–LDH and Zn–Al–LDHs. At high loadings, direct transmittance (YDirect) decreased, while the light scattering in the coatings improved with respect to the neat epoxy. The highest Zn–Al–LDH loading (3.0 wt%) slightly deteriorated the transparency (YDirect = 93.3), but it was still higher than that of epoxy nanocomposite containing 0.5 wt% Mg–Al–LDH (YDirect = 89.8). A Good label was assigned to the epoxy nanocomposites containing up to 1.0 wt% Zn–Al–LDH, while epoxy/Mg–Al–LDH nanocomposites were Poor in terms of the CI labeling when Mg–Al–LDH content was more than 0.1 wt%. An increase of about 28 °C in the Tg value after the addition of 0.1 wt% Zn–Al–LDH indicated that Zn–Al–LDH can make strong the interaction between the epoxy matrix and nanoplatelets. However, decrease in the Tg of the epoxy/Mg–Al–LDH nanocomposites was a signature of the weak interactions between the Mg–Al–LDH nanoplatelets ‎and epoxy matrix due to inappropriate dispersion. In general, it was revealed for the first time that the CI enables correlating the chemical crosslinking with the photophysical properties of the epoxy/LDH nanocomposites.