Interply Hybrid Composites Research Articles

Mechanical properties of interply and intraply hybrid laminates based on jute-glass/epoxy composites

Currently, hybridization of natural-synthetic fibers within a polymeric matrix has received wide attention owing to its promising properties. This study investigated the mechanical properties of interply and intraply hybrid jute (J)-glass (G) fiber/epoxy composites. The mechanical properties (i.e., tensile, flexural, and impact) of the pure jute, pure glass, and their hybrid composites were evaluated. The prepared composite samples consisted of five plies of woven fabrics. Interply hybrid composites comprised three layering sequences: G3JG, GJGJG, and 2GJ2G. Intraply hybrid composites of similar co-woven plies were fabricated by either the alternative replacement of a single glass yarn with a single jute yarn (G1J1) or two jute yarns (G1J2). The results showed that increasing the glass fraction in the interply hybrid composites improved their tensile properties. The two intraply hybrid composites provided almost similar tensile moduli, while the tensile strength of the G1J1 samples was approximately 41% higher than that of the G1J2 counterparts. The maximum flexural properties were provided by 2GJ2G composites, followed by GJGJG, and they were interestingly higher than those of pure glass composites. The G1J1 intraply hybrid composites offered a higher flexural strength and a lower flexural modulus than those provided by the pure glass composites. Compared to the pure glass composites, the impact strengths of the 2GJ2G and GJGJG samples decreased by 4% and 16%, respectively. In summary, the GJGJG hybrid composites exhibited the highest specific tensile, flexural, and impact properties compared to the other hybrid composites.

The effect of multiscale Kevlar/Glass hybridization on the mechanical properties and the damage evolution of 3D orthogonal woven composites under flexural and impact loadings

This work aims to evaluate the effectiveness of inter-ply/intra-tow hybridization in 3D woven composites to achieve an ameliorated impact and flexural performance. In this regard, inter-ply/intra-tow hybrid epoxy composites with Kevlar, E-glass, and ultra-high-molecular-weight polyethylene (UHMWPE) reinforced 3D fabrics are manufactured using the vacuum infusion method. To scrutinize the static and dynamic responses, the produced composites are subjected to flexural and low-velocity impact (50, 100, and 150 J) tests. The findings show that inter-ply hybrid composites exhibit more improved impact and flexural performance than their intra-tow hybrid counterparts. While the elastic moduli and strength values of weft-directional hybrid composites increase, on the contrary, warp-directional counterparts do not display an enhancement in flexural performance. Scanning electron microscopy (SEM) examinations and acoustic emission analysis are conducted together on the bending specimens to understand failure mechanisms leading to observed mechanical responses.

Mode I and II interlaminar fracture toughness of glass/carbon inter‐ply hybrid FRP composites: Effects of stacking sequence and testing temperature

AbstractEven though laminated FRP composites show exceptional performance in various modes of loading, they are susceptible to delamination. The ambient temperature and elevated temperature delamination resistance of glass/carbon fiber interply hybrid composites were assessed via mode I and mode II interlaminar fracture toughness tests performed at 30, 50 and 70°C. Interply hybrid composites performed better than composites with single type of fiber. The fracture toughness of inter‐ply hybrid composites varied with the stacking position. At 30°C, mode I fracture toughness value of alternative glass and carbon fiber stacking sequence (G1C1)5 of hybrid composite showed 40% improvement over 10 layered carbon/epoxy (C10) composite. Further, Mode II fracture toughness of C5G5 composite showed 22% enhancement, and C10 exhibited 42% improvement over 10‐layered glass/epoxy composite. Increasing the test temperature of all composites improved their GIC and GIIC values. The increment in the mode I fracture toughness properties of all composite was in the range of 5%–23% at 70°C from its room temperature value. The fractographic images of fractured samples were studied under a scanning electron microscope and failure mechanisms of composites were identified.

Repeated impact behaviour of inter-ply hybrid aramid/S2-glass epoxy laminates

This paper presents an experimental study on the repeated low-velocity impact behaviour of inter-ply hybrid composites of aramid/S2-glass/epoxy. The impacts were performed using a drop-tower apparatus following ASTM D7136 Standard. Two energies (19 and 37 J) were chosen for the study with up to twenty and five repeated impacts, respectively. A double exponential empirical model is proposed to describe the degradation due to the repeated impacts, considering the hybridization ratio. The impact response and progressive damage are presented and discussed for different laminates: single-fibre, and asymmetric or symmetric hybrids. The results show that hybridization may lead to the mitigation of repeated impact degradation. For asymmetric hybrids, impact on S2-glass showed a combination of higher impact stiffness and lower degradation rate, outperforming single-fibre laminates.

Evaluation of tensile properties on glass/carbon fiber epoxy pure, interply, and locally nested intraply hybrid composites

AbstractIn this study, the behavior of pure glass fiber/epoxy, pure carbon fiber/epoxy, interply hybrid, and locally nested intraply hybrid composites under tensile load was investigated. The specimens were produced by the vacuum‐assisted resin transfer molding (VARTM) method. Interply hybrid composites showed approximately the average tensile strength of the glass and carbon fiber/epoxy composites, with 603 MPa. Intraply hybrid composites had 17% lower tensile strength than pure glass fiber/epoxy composites due to the discontinuity of the fibers in the structure. Therefore, pure or interply hybrid composites are suitable in cases where tensile strength is more important, while in special cases where different properties are desired in different regions of a monolithic structure, locally nested intraply hybrid composites can be used. While the finite element analysis (FEA) results of pure and interply hybrid composites were very close to the tensile test, the amount of deviation increased in intraply hybrid composites due to fiber discontinuity. Fiber and void volume fractions of hybrid specimens were found to be around 62% and 1.45%, respectively. The numerical and experimental results of pure carbon fiber/epoxy composite are validated by the analytical solution.

Numerical investigation on the hybridization effect in inter-ply S2-glass and aramid woven composites subjected to ballistic impacts

Hybrid composites may be used to improve the ballistic properties of structures. These composites may be produced by enhanced manufacturing process that allow obtaining desired protection level and reducing costs. However, large variability in the material selection and architecture makes the correct choice a complex task that, in the past, has been mainly faced by experimental technique.To reduce experimental efforts, the use of predictive modelling approaches is a current attractive possibility. This work focuses on numerical simulations of the ballistic impact on different combinations of inter-ply hybrid composites of woven Kevlar and S2-glass. The numerical analyses are carried out employing LS-Dyna MAT_162, which accounts for progressive inter- and intra-laminar failure modes. Some materials mechanical properties are obtained through tests and the parameters accounting for strain rate and softening are calibrated. This is crucial to obtain an accurate model, avoiding to address the calibration task in a pure numerical and parametric way. The effect of the stacking sequence and target thickness on the ballistic curves, the ballistic limit velocity and the absorbed energy by the target, are discussed. The numerical models show high accuracy in predicting the residual velocity, ballistic limit and damage features.

WITHDRAWN: A review on different hybrid composites for aircraft structures

Composites have been used in motorsports, aviation and many industrial machines for decades. In this paper, the recent research works on composites are reviewed. This work explores the possibility of using carbon fiber in different sequences of an inter-ply hybrid composite. This review also concentrates on various tests conducted on a select few composites to test their strength in different areas. The visco-elastic properties of these hybrid composites can be found out by performing dynamic mechanical analysis. Further analysis will be conducted in finite element analysis software. From the results, the most optimal hybrid configuration can be found out.

WITHDRAWN: Vibration analysis of fiber reinforced polymer interply hybrid composite

Composite material is one of the necessities in this time for reduction of weight and material cost. We replace the material by the composite materials, its moves products in less cost and less weight. In this paper, the polymer hybrid reinforced composite material made by the hand layup method and vibration analysis is made on that. Here E glass fiber and carbon fiber with combination of resigns known as hardener and epoxy. The samples pieces are give three different names as S1, S2 & S3. All of the three samples are tested by the tensometer machine with ASTM standards. Finally, the vibration analysis is done by the workbench (ANSYS).

Interfacial performance and impact resistance of argon plasma treated UHMWPE/STF inter-ply hybrid composites

This study explored the influence of low temperature glow discharged argon (Ar) plasma on interfacial performance and impact resistance of ultra-high molecular weight polyethylene (UHMWPE) inter-ply hybrid composites. The composites were composed of UHMWPE and meta-aramid plain woven laminates with shear thickening fluid (STF). Water contact angle and drop-weight resistance of the composites with various Ar plasma treatment parameters were tested to investigate the interfacial performance and impact properties of the composites. The tested treatment parameters of this study included treating time, treating power, and gas flow rate. It was found that the best interfacial adhesion of UHMWPE and the impact resistance of the composites was realized at the plasma treatment power of 100 W, treatment time of 150 s, and gas flow rate of 4 sccm. In the follow-up research, this study conducted ballistic test to further explore the bulletproof effect and application prospect of this material.

WITHDRAWN: Vibration analysis of fiber reinforced polymer interply hybrid composite

Composite material is one of the necessities in this time for reduction of weight and material cost. We replace the material by the composite materials, its moves products in less cost and less weight. In this paper, the polymer hybrid reinforced composite material made by the hand layup method and vibration analysis is made on that. Here E glass fiber and carbon fiber with combination of resigns known as hardener and epoxy. The samples pieces are given three different names as S1, S2 & S3. All of the three samples are tested by the tensometer machine with ASTM standards. Finally, the vibration analysis is done by the workbench (ANSYS).

Vibration analysis of interply hybrid composite for an aircraft wing structure

Due to the rise in environmental issues the research and development of natural and synthetic fibers have risen exponentially for various industrial applications. Research is going on to develop newer fiber-reinforced plastic composites in order to replace metals and alloys. Due to the flexibility composite materials offer compared to metals there has been many innovations coming up in the aerospace industry. Composite materials due to their most desirable property, the high strength to weight ratio have play a major role in weight reduction, and they used for both structural applications and components of all automobiles and space crafts. With primary focus of aerospace industry being to reduce weight and thereby reducing fuel consumptions. The objective of this project is to design and fabricate a simple airfoil wing skin using hybrid composites and to experimentally study its vibrational behavior. The primary focus of this project is to understand the effect of hybridization on the mechanical properties namely vibrational behavior of composite structures. The composites used are carbon, aramid, basalt and glass fibers. The specimens were fabricated by the simple and most common hand lay-up method. The hybrid configurations fabricated were CGC (carbon/glass/carbon), AGA (aramid/glass/aramid) & BGB (basalt/glass/basalt). Free vibration tests were performed to study their natural frequencies and also to understand their damping characteristics.

Effect of alkali treatment on adhesion of thermoplastic polyurethane elastomer/polyester inter-ply hybrid composites

PurposeThe purpose of this paper is to investigate the effects of alkali treatment on adhesion of industrial thermoplastic polyurethane elastomer (TPU)/polyester woven fabric inter-ply hybrid composites.Design/methodology/approachInter-ply hybrid composites were exposed to varying concentration of sodium hydroxide at different temperature and time and their mechanical properties including differential scanning calorimetry, scanning electron microscope, tensile and peeling strength evaluated to determine optimal treatment parameters.FindingsModified polyester fabrics treated with alkali had higher tensile and peeling strengths. Accordingly, alkali treatment roughened the surface of polyester fabric, decreasing warp and weft densities, thus increasing fiber surface energy. The fabric had the highest peeling strength of 3.23 N/mm at treatment of 25% concentration of sodium hydroxide (NaOH). Short-term exposure to ultraviolet had little effect on interfacial adhesion of alkali-treated conveyor belt.Research limitations/implicationsPolyester fabric, applied in reinforcing industrial conveyor belts, is never degreased, roughened, sensitized or activated. In this paper, one-step treatment of polyester fabric was performed to increase its adhesion with polyester inter-ply hybrid composites, providing a reference for practical industrial application.Practical implicationsThe method developed in this research is simple and provides a solution to improving the interfacial adhesion of TPU/polyester conveyor belt.Originality/valueThe novel alkali treatment technology has many applications in the interfacial performance of composite materials.

Mechanical properties of glass/carbon inter-ply hybrid polymer composites at different in-situ temperatures

An inter-ply hybrid composite consists of at least two types of reinforcements along different plies in fiber-reinforced polymer composites. The tensile behaviour is deteriorated with increasing temperature, which possesses a severe concern that needs to be tackled before incorporating it into engineering applications. The tensile testing was done on the specimens at different temperatures (30 °C, 70 °C and 110 °C) by changing the hybrid ratio with different stacking sequence. The results reveal that by incorporating two layers of carbon fiber at the top end in glass fibers epoxy (GE) composite at 30 °C enhances the tensile modulus by 76.8% more than the control GE composite. Also, the strain to failure increases by 20.7% than carbon fiber reinforced epoxy (CE) composite by substituting one glass fiber by one carbon fiber at the top end. Although at 110 °C temperature, strain to failure amplifies by 9.3% than that of CE composite. The dominant modes of failure were observed under scanning electron microscopy of the failed specimens.

Progressive failure in interply hybrid composites of self-reinforced polypropylene and glass fibre

Hybridisation of two composites has the potential of tailoring properties to reach a composite structure with advantages of both constituents where the drawbacks are lessened. The current work reports this practice for self-reinforced polypropylene (SRPP) composites and glass fibre to create an interply hybrid composite with enhanced stiffness and ductility. The effect of glass fibre volume fraction, matrix adhesion, and layup, was studied as the parameters to affect progressive failure through pseudo-ductility. Hybrids with up to 6.5% glass fibre volume fraction showed pseudo-ductile behaviour. However, matrix adhesion and layup interfered with this effect. It was found that composites with low adhesion matrix exhibited higher pseudo-yield strain, and for the laminates with an interleaved layup, the maximum glass fibre volume fraction for progressive failure increased by 100%. The impact behaviour of the composite laminates also demonstrated that brittleness of the glass fabric reduces the energy absorption capability of the laminates compared to SRPP composite of the same thickness.

High strain rate compression testing of intra-ply and inter-ply hybrid thermoplastic composites reinforced with Kevlar/basalt fibers

In this study, the influence of hybridization on the compression response of thermoplastic matrix-based composites under high strain rate loading was investigated. The intra-ply and inter-ply hybrid composites were manufactured with Kevlar/Basalt yarns as the reinforcements with Polypropylene as a matrix. Cylindrical composite specimens were laser cut from the flat compression moulded laminates. The composite specimens were loaded under high strain rate using split-Hopkinson pressure bar setup at strain rates ranging from 2815/s to 5481/s. The study revealed differences in the rate-dependent growth of peak stress, peak strain and toughness with the strain rate. Intra-ply hybrid composites with alternate weaving of Kevlar and basalt yarns exhibited highest peak stress as compared to the Inter-ply hybrid composites (alternate layers of Kevlar and basalt fabrics) and another intra-ply composite containing Kevlar in the warp and basalt in the weft direction. Whereas in inter-ply hybrid composite, with Kevlar as the loading face attained higher stress, while composite with Basalt as the loading face attained higher strain. SEM micrographs revealed that Kevlar on the loading face can bear the impact with lesser delamination as compared to the Basalt on the loading face. Damage studies revealed that Kevlar fiber surface loading results in higher stress as compared to basalt (brittle) surface loading with lower overall damage.

Influence of Fiber Stacking Sequence in Inter-ply Hybrid Composites Structures on the Mechanical and Dynamics Properties

Son yıllarda geliştirilen yeni üretim metotları ile tabakalı kompozit yapıların kullanım alanları dikkatedeğer bir şekilde artmıştır. Bu yapıların kullanım performanslarını arttırmak amacıyla farklı tekil kumaşlar,farklı diziliş sıraları ile aynı kompozit yapıda kullanılarak hibrit kompozit yapılar elde edilmiştir. Tabakalı hibritkompozit yapıların mekanik özellikleri ile ilgili birçok araştırma yapılmışken dinamik özellikleri ile ilgili yapılanaraştırmalar henüz yeterli değildir. Bu çalışma kapsamında; tekil cam (C) ve tekil karbon (K) elyaflar kullanılarakVARTM (Vakum Destekli Reçine Transfer Kalıplama) yöntemi ile 4 tabakalı, 4 farklı diziliş sırasına sahipnumunelerin üretimi gerçekleştirilmiştir. Bu numuneler; sade cam (C4), sade karbon (K4) olmak üzere iki tekilkompozit yapı ve bu iki elyaf türünün aynı yapı içerisinde simetrik olarak farklı diziliş sıralarıyla kullanılmasıylaelde edilen iki farklı hibrit kompozit yapıdan (KCCK ve CKKC) oluşmaktadır. Üretilen kompozit levhalardan,ilgili ASTM standartlarına göre üç nokta eğilme, çekme ve titreşim testleri için gerekli olan numuneler kesilerekelde edilmiştir. Üç nokta eğilme testleri yapılarak numunelerin maksimum eğilme dayanımları ve çekme testleriyapılarak numunelerin elastisite modülleri belirlenmiştir. Ayrıca ankastre-serbest sınır şartında serbest titreşimanalizleri yapılarak doğal frekans ve sönüm oranı değerleri tespit edilmiştir. Elde edilen sonuçlar ile interply hibritkompozit yapılarda diziliş sırasının maksimum eğilme dayanımı, elastisite modülü ve titreşim özelliklerine etkisiincelenmiştir.

Advanced 3D and 2D damage assessment of low velocity impact response of glass and Kevlar fiber reinforced epoxy hybrid composites

This work focuses on quasi-static mechanical (tensile, flexural, indentation), low velocity impact (LVI) and viscoelastic behaviour of different stacking sequences and ] of 16 layers woven roving Kevlar-E-glass/epoxy interply hybrid composites. The outermost layers are Kevlar and remaining 14 E-glass layers are placed as interior for making these hybrid laminates. The viscoelastic properties are measured over the temperature range from 25 °C (room temperature) to 180 °C at three different frequencies (1, 10 and 50 Hz) by using the dynamic mechanical analyzer (DMA). The LVI results indicated that Kevlar-glass/epoxy hybrid laminates exhibit the highest damage threshold load (DTL) whereas laminates possess the higher peak load and threshold and maximum energies. Advanced non-destructive testing techniques (NDT) such as X-ray computed tomography (X-CT) and ultrasonic C-scan are employed to evaluate the micro and macro damage mechanisms of LVI tested specimens, respectively. Detailed observations have been made on the onset and growth of cracks in 30°, 45° and 0° plies using X-CT scan imaging. These images show that the bottommost plies subjected to more impact than the topmost plies, the outer Kevlar plies protect the inner 0° glass plies and delays the delamination propagation. ‘C’ scan images indicate that laminates spread the damage to more area. The scanning electron microscopy (SEM) is used for examining the failure mechanisms of indentation specimens.

Mechanical properties of inter-ply hybrid composites reinforced with glass and polyamide fibers

The aim of this study is to explore the possibility of using polyamide (PA) as a reinforcement with glass (G) fiber to form new hybrid composites with improved physical and mechanical properties. PA-G–reinforced epoxy hybrid composites were designed, fabricated using the hand layup technique in inter-ply configuration and their mechanical properties were investigated. Results are presented regarding the tensile, flexural, and in-plane shear behaviors of the fabricated composites with a particular consideration of the effects of the stacking sequence and PA-fiber relative volume fraction, ( vPA/ vtot). The experimental results reveal that the existence of G-fiber at the composite external layers and PA-fiber in the core improves the tensile and flexural properties but worsens the shear properties. Also, increasing ( vPA/ vtot) upgrades the tensile properties but deteriorates the flexural and shear properties. The merits of the hybridization in the current study are lesser cost compared to pure PA-composite and lightweight and better ductility compared to pure G-composite with improved mechanical properties. As a result, these hybrid composites are suitable for medium load applications.

Hybrid effect of carbon nanotube film and ultrathin carbon fiber prepreg composites

This paper successfully interlaced floating catalyst chemical vapor deposition-grown carbon nanotube film and ultrathin carbon fiber prepreg to achieve strong and flexible carbon nanotube/carbon fiber hybrid composites with high carbon nanotube loading. Epoxidation was also introduced to improve interlaminar interfacial bonding. It was found that pristine carbon nanotube film/carbon fiber interply hybrid composite (carbon fiber/carbon nanotube/carbon fiber) showed sudden and brittle failure, while epoxidation caused a gradual failure behavior. Hybrid effect analysis suggested that the improved tensile performance and synergistic effect of epoxidized carbon nanotube film/carbon fiber hybrid composite were attributed to good load transfer and suppressed delamination induced by improved interfacial bonding. In addition carbon fiber/carbon nanotube/carbon fiber manifested excellent damping capacity with the maximum loss factor of 0.13. The in-plane electrical conductivity of composite with global carbon nanotube content of 21 wt% increased to the same order of magnitude as carbon nanotube film composite. The excellent mechanical, damping, and electrical properties demonstrated great potential for both structural and multifunctional applications of the resultant hybrid composites.

Experimental and numerical investigation of interply hybrid composites based on woven fabrics and PCBT resin subjected to low-velocity impact

Low-velocity impact response of interply hybrid composites based on glass and carbon woven fabrics as reinforcement and polymerized poly (butylene terephthalate) (PCBT) as matrix was presented in this paper. Experiment and finite element method (FEM) were respectively performed to investigate the hybridization effect on the composites under impact velocity of 3m/s, 5m/s and 7m/s. Specimens used in the experiment were made by vacuum assisted prepregs process (VAPP). All the material parameters used in simulation were determined by experimental test. Three-dimensional finite element models were developed in ABAQUS/Explicit to analyze the damage behavior of interply hybrid composite laminates, and a user subroutine VUMAT was compiled for the woven fabrics reinforced PCBT composites. Experimental results show that hybrid composites at hybrid mass ratio of 37:63 could absorb more energy in the impact event compared with pure composites, and the perforation thresholds enhance significantly. The simulation results are well agreed with experimental results. The damage mode of the interply hybrid composites under low-velocity impact is further discussed.