Tensile Properties Of Composites Research Articles

Effect of hybridization on crystallization behavior, mechanical properties, and toughening mechanisms in rubber-modified polypropylene flax fiber composites

Nowadays, the significance of sustainability has urged composite manufacturers to replace traditional synthetic fibers with eco-friendly natural alternatives due to their environmental and economic benefits. This work aims to fabricate hybrid polypropylene (PP) composites with short flax fibers, octene-ethylene copolymer (POE) rubber particles, and maleic anhydride-grafted polypropylene (MAPP) compatibilizer. The main goal is to gain an insight into the combined effect of toughening mechanisms induced by the short fibers and rubber particles at the crack tip and wake of composites, which is a crucial step in reaching a balance between toughness and rigidity. In this regard, a novel microscopy strategy is taken to elucidate the operating mechanisms at the crack tip and crack wake of composites. Also, differential scanning calorimetry (DSC), tensile, and Charpy impact tests were employed to investigate the effect of hybridization on the crystallization behavior, tensile, and impact properties of composites. The experimental results showed that the combined effect of encouraging matrix plastic deformation and synergistic work of toughening mechanisms at the crack tip and wake in the MAPP-modified hybrid composites containing 30% flax fibers and 10% POE rubber particles yielded an optimal improvement of 315%, 135%, and 37% in impact strength, elastic modulus, and ultimate tensile strength, respectively, over the neat PP formulation.

Tensile and microstructural properties of unidirectional coir bio-derived epoxy composites

The study investigates the possibilities of reinforcing bio-derived epoxy (bio-epoxy) polymer with unidirectional arrays of coir fibre using hand layup. The coir fibres were unidirectionally prepared in two layers. The tensile properties such as strength, Young’s modulus and elongation at break were found to be 43.83 MPa, 2.4 GPa and 2.72 % respectively. The tensile strength of coir/bio-epoxy composite was higher than the unreinforced bio-epoxy resin. The fibre volume fraction of the composites obtained using ImageJ on an 8-bit grey scale was 34%. The optical microstructure of the composites shows the distribution of the fibres within the bio-epoxy matrix.

Effect of incorporation of sugar palm (Arenga Pinnata[Wurmb] Merr.) fiber from various geographical regions towards the tensile and flexural properties ofSPF/epoxy composites for engineering applications

AbstractThe objective of this study is to evaluate the tensile and flexural properties of epoxy composites reinforced with sugar palm (Arenga pinnata) fiber (SPF) harvested from various geographical locations, in Malaysia; Kuala Jempol, Negeri Sembilan (SPFN9); Benta, Pahang (SPFP); and Tawau, Sabah (SPFS), and from Java, Indonesia (SPFJ). Due to its optimal chemical composition, which includes a higher proportion of cellulose (44.53%), hemicellulose (10.01%) and lignin (41.97%), SPFN9/epoxy composites have the best tensile and flexural strength, according to this study, with 27.09 MPa and 54.44 MPa, respectively. The composites demonstrate slight decreases in the tensile strength (about 27–36%) and flexural strength (about 26%–42%) compared to the neat one. This is associated with the insufficient filling of the polymer amount. The hydrophilic characteristic of SPF makes it tough to bind to hydrophobic epoxy, creating a difficulty with interfacial adhesion between the filler and matrix. Thus, the SPF needed to be treated prior to the fabrication of composites to improve its mechanical properties for structural and automotive applications.

Mechanical and Water Absorption Properties of Jute/Palm Leaf Fiber-Reinforced Recycled Polypropylene Hybrid Composites

Hybrid composites have proven endless benefits to the research communities in terms of environmental friendliness, mechanical properties, and development of new material. The present work explores the tensile, flexural, impact strengths, and water absorption properties of jute and palm leaf fiber-reinforced hybrid composites. Five types of hybrid composites were fabricated by varying jute and palm leaf fiber percentage of J100:P0, J25:P75, J50:P50, J25:P75, and J0:P100% with a constant weight ratio of polypropylene matrix. The findings showed that jute-palm leaf fiber-reinforced composite had positive effect on tensile, flexural, and impact strength. Experimental results showed that the J25:P75% (jute and palm leaf fiber) exhibited the highest tensile strength of 62.2 MPa and flexural strength of 82.26 MPa due to the optimal interfacial properties between the fibers and matrix. The impact strength of composites increased as the proportion of palm leaf fiber increased. Water absorption increased with jute fiber content, reaching a maximum of 1.26% at composite J100:P0, with lower water absorption at J0:P100% composite due to the higher moisture content of jute fiber.

Enhancement of tensile, flexural and ILSS properties of C-epoxy composites with the addition of ETBN toughener and Af-MWCNTs

The objective of this research is to develop a hybrid composite with a unique combination of features such as tensile, flexural and Interlaminar shear strength (ILSS) properties. It is a present need for components used in underwater, aerospace, defence and automotive applications, as parts are subjected to a variety of loading conditions, including tensile, bending and shearing. Carbon fibre reinforced epoxy (C-epoxy) composite is modified by adding epoxy terminated butadiene acrylonitrile (ETBN) liquid rubber and amino-functionalized multi-walled carbon nanotubes (Af-MWCNTs). With the addition of ETBN, the tensile, flexural and ILSS properties were improved by 38%, 46% and 80%, respectively. The addition of 0.5wt% of Af-MWCNTs improved the tensile and flexural strengths by a maximum of 59% and 61%, respectively. In contrast, the maximum improvement in ILSS of 120% was obtained at 1.0 wt.% of Af-MWCNTs. The unique combination of C-epoxy-ETBN-Af-MWCNTs led to the formation of the serrated surface at the fibre matrix interface, which caused improved energy absorption. The toughening mechanisms which are responsible for the improvement in properties are discussed and the results are validated through finite element analysis (FEA).

Pengaruh Larutan Natrium Hidroksida Terhadap Kekuatan Komposit Serat Sabut Kelapa

Abstract: The purpose of this study was to determine the effect of soaking coconut fiber in sodium hydroxide solution on the strength of the coconut fiber composite. This research was divided into several stages, namely: preparation of materials and tools, the process of soaking coconut fiber, making coconut fiber composites, testing the tensile and flexural properties of coconut fiber composites, and analyzing the test results. Coconut fiber is soaked in sodium hydroxide solution, then dried in an oven, then used as a composite reinforcement using BQTN 157 polyester resin with a composition of 5% coconut fiber. Based on the results of the tensile test according to the ASTM D638-03 standard, and the flexural according to the ASTM D790 standard, it was concluded that the process of soaking coco fiber in sodium hydroxide solution of 5%, 10%, 15%, and 20% had not been able to increase the strength of the coco fiber composite with composition of 5% coconut coir fiber compared to the strength of the resin.

Meso-scale Finite Element (FE) modelling of biaxial carbon fibre non-crimp-fabric (NCF) based composites under uniaxial tension and in-plane shear

Non-crimp-fabrics (NCF) are promising materials in aerospace applications. The complex internal structure of NCF composites could influence the in-plane performances, which needs to be comprehensively studied. The novel three-dimensional (3D) meso-scale repeated unit cell (RUC) models were proposed for biaxial NCF composites based on the Finite Element (FE) method to conduct a systematic parameter study, including layup sequence, out-of-plane tow waviness, resin-rich areas, transverse tow placements and delamination. The meso RUC model could effectively predict the homogenised uniaxial tensile and in-plane shear properties of biaxial NCF composites based on their meso-scale constituent and material properties. A multiscale framework was also developed for biaxial NCF composites. A micromechanical representative volume element (RVE) model provided homogenised mechanical properties for tows, and a macroscopical FE model validated the test results using the homogenised results obtained from meso RUC models. The numerical results were in good agreement with the experiment results. Therefore, the multiscale framework provides an insight into the critical parameters influencing the in-plane properties of NCF composites and an analysis tool for NCF material design.

Investigating the Effect of Reinforcing Particles Size and Content on Tensile and Fatigue Properties of Heat-Treated Al7075-SiC Composites Fabricated by the Stir Casting Method

Investigating the Effect of Reinforcing Particles Size and Content on Tensile and Fatigue Properties of Heat-Treated Al7075-SiC Composites Fabricated by the Stir Casting Method

Effect of particles on tensile and bending properties of jute epoxy composites

Abstract In this investigation, mechanical properties of composite materials produced from woven jute type were investigated. These composites were produced in the form of epoxy adhesive layers by using hand lay-up method in which aluminum, mica and ceramic particles were added into epoxy as a structural adhesive by 2, 4 and 6 wt%. Samples produced according to ASTM D procedures were subjected to tensile and three point bending loads to examine the effect of the particles. Experimental results were presented in tables and graphs. As a result, it was observed that the tensile and bending failure loads of the composite materials obtained by using the particle reinforced adhesive increased. Also, the biggest rise in tensile strength was achieved with 4 wt% aluminum and the biggest increase in bending strength was observed for 2 wt% aluminum particles.

Utilization of kenaf fiber waste as reinforced polymer composites

The textile industries produce huge KF waste which should be utilized optimally. In this study, the KF waste was used to produce a composite. The mechanical properties of KF waste reinforced composites were observed. The important factor which affects the mechanical properties is the fiber configuration. Tensile and flexural tests were used to characterize the composite's products. The tensile properties were evaluated according to ASTM D-638, while the flexural properties were examined following ASTM D-790. The results showed that the unidirectional fiber orientation had the highest tensile (76.5 MPa) and flexural (151.3 MPa) strengths. The results show that the polyester composites reinforced with KF waste exhibit equivalent tensile and flexural properties of composites composed of regular KFs if arranged in unidirectional orientation. Thus, the appropriate fiber orientation gives the best composite results.

Effect of Chemical Treatment on Mechanical and Morphological Properties of Sugarcane Bagasse Reinforced Unsaturated Polyester Composite

The purpose of this research is to study the mechanical and morphology of sugarcane bagasse (SGB) reinforced unsaturated polyester resin (UPR) composites by utilizing a different percentage of fibre contents and different chemical treatments on fibres. Sugarcane bagasse reinforced unsaturated polyester resin composites have been prepared using the compression molding technique. To enhance better adhesion between fibre and matrix, the SGB was chemically treated with alkaline (NaOH) solution and silane solution for 2 hours. The characterization of mechanical properties such as tensile and flexural strength, and tensile and flexural modulus of SGB-UPR composites were studied and compared. The incorporation of the alkaline + silane treatment of SGB resulted in better tensile and flexural properties of composites than untreated or alkaline-only treated SGB composites. Overall, it can be seen that the 5 % of fibre treated with NaOH + silane treatment showed the best results for tensile and flexural properties. Surfaces of cracked composites were observed using SEM and treated SGB showed better interfacial adhesion with matrix rather than the untreated SGB. Chemical treatment plays an important in enhancing the interfacial adhesion of fibre and matrix in composites.

Micromechanical Modeling for Tensile Properties of Wood Plastic Composites: Use of Pruned Waste from Pecan Orchards as Sustainable Material for Reinforcement of Thermoplastic Composite.

Wood plastic composites (WPCs) specimens containing high-density polyethylene (HDPE) and wood pruning waste were manufactured and evaluated for their mechanical properties. Pecan waste was used as an accessible and sustainable source in this study, and the effects of its particle size and concentration on WPC strengths were evaluated. Pecan waste was milled and sieved to various particle sizes, and testing samples were fabricated by mixing them in a twin-screw extruder and injection molding. A coupling agent was used to create a stable bond between the HDPE and wood. Both tensile modulus and strength were increased with an increasing pecan flour concentration up to about 60 weigh percent. A micromechanical model is proposed for predicting the mechanical properties of the wood flour/fiber reinforce composite. This model uses a correction factor of an elliptical of carried sizes and shapes. The preliminary results of the model have a high correlation with the experimental values of the composite in all mesh sizes.

Effects of environmental temperature on the mechanical properties of polyethylene fiber‐engineered cementitious composites

AbstractEngineered cementitious composites (ECC) incorporated with synthetic fibers possess extraordinary tensile capacity; however, temperature sensitivity of synthetic fiber arouses concern about the reliability of ECC working at extremely environmental temperature. This article is aimed to study the influence of environmental temperatures, from −20 to 90°C, on the mechanical properties of polyethylene (PE) fiber reinforced ECC (PE‐ECC). Experiments were conducted from four different angles, that is, compressive, and tensile properties of composites, fiber bridging behavior of composites, fracture toughness of cementitious matrix, and tensile property of PE fiber bundle. It is demonstrated that temperatures have significant impacts on the tensile and compressive strength of PE‐ECC. Furthermore, the test results indicated that the tensile strength of PE fiber, fracture toughness of matrix and fiber bridging strength all decreased, while the elongation of fiber and crack opening displacement are increased with temperature increasing from −20 to 90°C. On this basis, a pseudo‐strain‐hardening index is utilized to explain the mechanism underlying the temperature‐dependent behaviors of PE‐ECC.

Tensile and flexural properties of polyester composites reinforced by iron filings

The effects of iron filings on the tensile and flexural properties of unsaturated polyester reinforced by iron filings have been studied. Particulate polyester composite reinforced by iron filings of different wt. % were synthesised and characterised. The mass percentage of the iron filings, varied from 0, 5, 10, 15, 20, 25 to 30 % were added to unsaturated polyester resin with 2 grams of methyl ethyl ketone peroxide catalyst and 0.5 grams of cobalt naphthalene accelerator to synthesise the composites. Tensile and flexural tests were carried out on the samples. The metallographic study was carried out using an optical microscope and scanning electron microscope. Results showed that tensile properties, including energy absorbed at fracture, percentage elongation, and tensile strength of the composite improved with increasing wt. % of filing particles up to 15 wt. %. This trend was also observed in the flexural strength results. The sample with 15 wt. % iron filings was observed to have the optimum reinforcement effect with a tensile strength of 34.91 MPa, a flexural strength of 111.06 MPa, and a modulus of elasticity of 1581.29 MPa.

Microstructure and Tensile Properties of Ductile Cast Iron Composites Reinforced by Tic Nanoparticles

Microstructure and Tensile Properties of Ductile Cast Iron Composites Reinforced by Tic Nanoparticles

Impact of B4C reinforcement on tensile and hardness properties of Al-B4C metal matrix composites

As compared to unreinforced alloys, metal matrix composites (MMCs) have considerably better properties such as extraordinary specific strength, damping power, precise modulus, and strong wear resistance. There has been an increase in research into producing composites with small density and low cost reinforcements, as well as their capability to be manufactured using traditional approaches. A Toughening of aluminum metal matrixes is achieved by reinforcing them with hard ceramic particles such as Sic, Al2O3, and B4C, among others. The current study aims to improve the mechanical properties of AMCs such as rigidity and hardness by supporting the 6061Al structure with B4C particles. Aluminum lattice was made up with boron carbide average particulates of 40 µm sizes using a combination projecting course. Fabricated AMCs' microstructure and mechanical properties were investigated. The SEM and optical microstructure of the composites demonstrates the homogeneous scattering of B4C particles. Tensile strength and hardness Properties were found to proliferation as weight percent of B4C was increased.

Microstructure and Tensile Properties of Ductile Cast Iron Composites Reinforced by Tic Nanoparticles

Microstructure and Tensile Properties of Ductile Cast Iron Composites Reinforced by Tic Nanoparticles

Tensile and Liquid Absorption Properties of Polyester-based Composites as Alternative Marble Materials

Three polyester-based composite materials were prepared with different volume fractions of three types of fillers (i.e. cement, gypsum and limestone) with the aim of improving the tensile and liquid absorption properties of the former for the synthetic marble industry. The tensile strength, modulus of elasticity, toughness, ductility and liquid absorption percentage of the composites were characterized. Results revealed an increase in the modulus of elasticity, tensile strength and toughness of all prepared composites, as well as a decrease in their ductility, with increasing filler amount. The liquid absorption values of all composites increased with increasing filler content. The composites were able to absorb water extensively but absorbed benzene, kerosene and gasoil minimally.

The effect of waterborne polyurethane coating on the mechanical properties of epoxy-based composite containing recycled carbon fibres

The current study focuses on the influence of waterborne polyurethane surface-modified recycled carbon fibre (rCF) on tensile, flexural, and low-velocity impact properties of the epoxy-based composite. The recycled carbon fibres were coated by five different concentrations of waterborne polyurethane (WBPU) bonded with 3-aminopropyltriethoxysilane. The chemical bonding between the fibres and the coating and their morphological structures are demonstrated by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), respectively. Furthermore, the single fibre tensile tests showed the enhancement of tensile strength and Young's modulus results after the coating. The thermal stability of the coated fibres was changed significantly compared to the uncoated fibres and the contact angle of their surface was reduced dramatically. The measured contact angles between the single fibres and the resin decreased from 70° to 40°. The epoxy-based composites were manufactured by the vacuum infusion method at room temperature. Significant improvements were attained in the tensile and flexural properties of the composites reinforced by coated fibres. The tensile and flexural strength of the mentioned composites were enhanced by up to 107% and 68%, respectively. Fractography confirmed the strong adhesion between the coated fibres and the matrix. Eventually, the impact resistivity of the fabricated composites was improved by approximately 49%.

Preparation of continuous glass fiber/polyamide 6 composites containing hexaphenoxycyclotriphosphazene: Mechanical properties, thermal stability, and flame retardancy

AbstractThe halogen‐free flame‐retardant continuous glass fiber/polyamide 6 (GF/PA6) composites containing hexaphenoxycyclotriphosphazene (HPCTP) were prepared by the resin transfer molding (RTM) process. The influence of HPCTP content on mechanical properties of GF/PA6 composites was studied. The addition of HPCTP has no obvious effect on the tensile properties of composites, and the tensile strength of GF/PA6 composites with the addition of 30% HPCTP reaches 425.2 MPa. However, with the addition of HPCTP, the flexural strength and interlaminar shear strength of GF/PA6/30%HPCTP composites decrease to 246.4 and 20.9 MPa, respectively. The flame retardancy, thermal stability, and burning behavior of the composites were evaluated by means of limited oxygen index (LOI), UL‐94, thermogravimetric analysis and cone calorimeter. The results show that the LOI value of GF/PA6 composites can reach up to 30.9% corresponding to the grade of UL‐94V‐0 with the addition of 30% HPCTP. The flame retardancy mechanism of GF/PA6/30%HPCTP composites is attributed to the combined effects of releasing incombustible gases in gas phase at the early stage and forming char layers in the condensed phase, which can dilute the concentration of combustible gas and retard the mass and heat transfer.