Carbon Fiber Layers Research Articles

Comparative analysis of Basalt/E-Glass/S2-Fibreglass-Carbon fiber reinforced epoxy laminates using finite element method

This paper aims to numerically analyse (using finite element methods) the static loading effects on basalt/E-glass/S2-fibreglass-carbon fibre reinforced epoxy hybrid composites, an alternative to the conventional and expensive pure carbon fibre epoxy composites. Structural properties of few hybrid composites are evaluated through static tests for validation purpose. The composite specimens comprising of four layers of carbon fibre and four layers of either basalt/E-glass/S2-fibreglass combined with LY556 resin in six varying stacking sequences are analysed for failure based on Tsai-Wu failure criteria. Commercial finite element software ANSYS Composite PrepPost (ACP) and ANSYS Mechanical were employed for this study. All specimen dimensions, boundary conditions and loading were adopted as per ASTM Standards. Results and discussion are followed by a significant comparison of static test results between basalt, E-glass, and S2-fibreglass each combined with carbon fibre epoxy. Finally, the optimal stacking sequence was found to be S2 - [02C/±45 M/0M]S. Basalt-carbon hybrids produced superior results in tensile and flexural tests while the brittle glass-carbon hybrids proved to be better in compression and in-plane shear. Laminates with carbon fibre at the outer layers showed improved performance among contemporaries.

Tensile and Stress Analysis of Hybrid Composite Prosthetic Socket Reinforced with Natural Fibers

Natural fibers and their composites are the evolving movements in material science, and with that, the utmost use of plant-based fibers has become the focus of this research. Sisal and cotton natural fibers were used to construct a prosthetic socket as an attempt to substitute material currently available in the manufacturing of sockets. The vacuum bagging technique was adopted to produce a below-knee socket. The influence of different fiber layering sequences on the volumetric and mechanical characteristics was estimated experimentally and numerically. Mechanical tensile tests were used to assess laminated specimens, such as tensile strength, young modulus, and elongation percentage. The number and type of reinforcing layers had an effect on mechanical properties, and the best composite specimens were three layers of sisal with two layers of carbon fiber, with tensile strength and modulus of elasticity reaching (261–4760) MPa, respectively. The finite element method (ANSYS- 16.1) was used to anatomize by seeing the contours distribution of safety factor, equivalent Von Mises stress, equivalent Von Mises strain, and total deformation. This procedure was executed by building ten models for the socket, which served as three-dimensional structural composite materials. The results of the present study advocate that the arrangement of natural and synthetic reinforcements allow the preparation of bio-composites with enhanced performance. This work revealed the assets of sisal and cotton fiber hybrid reinforced PMMA resin composites (hybridized at diverse volume percentages and lamination layup), which have not been tried up to now.

Numerical and experimental investigation of hinged Ankle-Foot-Orthoses (AFO) using composite laminate material for Cerebral Palsy patient

In this research, we tried to manufacture the AFO using composite material to enhance its strength and durability. As we know the shape of the ankle and leg part is complex to design, for designing and manufacturing, we went for the 3D modeling and 3D printing of the particular part. It made it easy for us to get the desired shape of AFO by considering its strength of it. We tested the laminated specimen of carbon fiber and PLA and got the result which showed that after layering the strength of the specimen got increased. The Young’s Modulus that we obtained for the only carbon fiber layer was 3.618 GPa. The Young’s Modulus obtained for the PLA with 100% and 50% infill density was 1.234 GPa and 0.976 GPa respectively. The Young’s Modulus obtained for the composite CF and PLA with 100% infill density was 2.163 GPa. The Young’s Modulus obtained for the composite CF and PLA with 50% infill density was 1.174 GPa. The experimental results were then validated with the Finite Element Analysis of the specimen. The error for the 0/90/PLA specimen and 0/90 CF specimen was 0.8% and 24.6%. This was within the acceptable range. The 3D printing process followed by the vacuum bagging process was carried for the actual model development. Finally, the Finite Element Analysis was done on the foot and upright part to study the stresses and deflection. The weight of the Carbon Fibre-Epoxy-PLA laminate manufactured AFO was 420 g. This weight included the accessories of the AFO too. The weight of the available AFO in the market is approximately 1.6 to 2 kg. Hence the reduced weight of the AFO was able to obtain in this research.

Evaluation of mechanical properties of CFRP modeled by FDM

Knee joint diseases have been increasing in recent years due to the aging of society and the increase in the sports population. Knee braces used in treatment play a role in immobilizing and stabilizing the knee joint and reducing the direct burden on the knee joint. Therefore, the development of knee braces using CFRP material by fused deposition modeling (FDM), one of the additive manufacturing (AM) methods, is expected. The application and development of CFRP for knee orthoses requires safe design that considers the weakest points in terms of the shape of the various parts used in the orthoses and the walking motion. However, the mechanical properties of CFRP materials using FDM have not been clarified. In this study, the effects of carbon fiber content and orientation on the flexural strength of FDM-molded CFRP were investigated. 4-point flexural strength tests revealed that the carbon fiber layer was distributed throughout the entire structure, and that the higher the fiber content, the higher the strength. Therefore, it is suggested that an even arrangement of the fiber and resin layers increases the bending strength.

Flexion in composite materials with different tensile and compressive response

An analytical and experimental study of flexural testing on laminates formed by layers of unidirectional carbon-fibres pre-impregnated with an epoxy resin is presented. Among other stacking sequences, the configuration comprised by groups of ±45° is of interest in the transport industry in which often there are structural parts subjected simultaneously to bending moments and shear forces. Having as a reference the three-point flexural testing, the work is focused on taking into account the different response of the material under tensile and compressive loads. From the experimental point of view, the damage initiation and evolution of the material are proposed to be visualized by means of optical methods and microscopy techniques, comparing the experimental observations with the analytical estimations. The analytical model used is based on the technique of homogenized section and it allows to predict the initial failure mode that will occur experimentally depending on the thickness of the specimen.

Behavior of Reinforced Concrete Beams Strengthened in Flexure using Externally Bonded Aluminum Alloy Plates

The utilization of carbon, glass, aramid and basalt fiber reinforced polymers (FRP) in shear and flexural strengthening of reinforced concrete beams have been well established and proved its effectiveness. As externally bonded strengthening materials, FRP composites have many advantages and some disadvantages. The main disadvantage of FRP composites are that they brittle materials. Aluminum Alloy (AA) plates are ductile materials, which is a desirable characteristics for reinforced concrete (RC) beams. This study investigated the structural integrity of RC beams strengthened in flexure using externally bonded AA plates. Four beams were cast and three of them were strengthened in flexure using AA plates. The AA plate covered 90% of the beams’ span and two of the beams were anchored at both ends of the AA plates using one layer and two layers of carbon fiber reinforced polymer (CFRP) laminates. The control beam was not strengthened and was therefore used as bench mark for measuring the performance the strengthened beams with and without anchorages. The beams were tested until failure under four-point bending. Load-deflection curves and load-strain curves were plotted and the ductility indices of the tested beams were calculated. It was observed that the strengthened beams showed increase in strength up to 40.3% and in ductility up to 55% of that of the control beam. However, the failure ductility of the strengthened beams with two layers of U-wraps decreased slightly, by 5% of that of the control beam. It can be concluded that AA plates could be used as strengthening materials to enhance the flexural performance of RC beams. In addition, the use of U-wrap CFRP anchorages influenced the types of failure modes of the tested beams.

Effectiveness of Nanosilica on Enhancing the Mechanical and Microstructure Properties of Kenaf/Carbon Fiber-Reinforced Epoxy-Based Nanocomposites

With an ultrasonic frequency of 15 kHz and an 850 W power capacity, the effects of nanosilica particle inclusion on the tensile, flexural, and impact properties of woven fiber-reinforced kenaf/carbon fiber/epoxy hybrid composites were explored experimentally. The nanoparticles were dispersed uniformly in the epoxy using an ultrasonic probe. Test samples were made according to ASTM requirements for three distinct weight compositions of nanosilica particles (1, 1.5, and 2 wt%). The composites were made utilizing the compression moulding process with the following parameters: (i) weight ratio of nanosilica, (ii) length of kenaf fibers, and (iii) number of carbon fiber layers to achieve the objectives above. According to unmodified samples, with a nanosilica concentration of 1.5 wt%, tensile strength improved by 31%, flexural strength increased by 42.36%, and impact strength increased by 22.65%. It was established that the interaction of micro silica particles with epoxy and fiber, which improved interfacial tension, had a substantial impact on mechanical and water retention capabilities. The 1.5 wt% nanosilica inclusion absorbs less moisture than the 1 and 2 wt% silica composites. A scanning electron microscope was used to examine the fractured surface of the tested nanocomposites.

Some effects accompanying delamination of CFRP under cyclic tension

The article presents the results of an experimental study of the processes of fatigue failure of layered carbon fiber reinforced plastics. The study was carried out on samples with a cross section of 15x25 mm subjected to cyclic tension with a maximum operating time of up to 1 million loading cycles. For loading the samples, a resonant testing machine was used - a high-frequency pulsator Zwick HFP 5100. During the operation the elastic system "machine-sample" is in resonance mode under the action of a variable load of constant amplitude.To determine the dynamic deformation fields, the digital image correlation (DIC) method implemented in the VIC-3D (Correlated solutions) experimental setup was used. Acoustic emission signals were recorded using an AMSY-6 system and two AE204A piezoelectric sensors, and the thermal state of the sample was assessed using an NEC TH9100 WR Pro New infrared camera.The dependences of the resonant frequency of specimens from the value of fatigue life are obtained. From the dependences obtained, it can be seen that with the accumulation of damage in the sample, the resonant frequency can abruptly decrease, and each decrease corresponds either to the appearance of a new macroscopic crack or its growth. The dependences of the number of acoustic emission events on time were also obtained. According to the dependencies obtained, each abrupt decrease in the resonant frequency of tests corresponds to an increase in the number of acoustic emission events. The appearance of delamination in the composite structure is accompanied by a local increase in temperature and strain.The obtained experimental data are supposed to be used to create fatigue damage models for layered polymer composite materials.

Analysis of Low-Velocity Impact Properties of Kevlar 149-Carbon Fiber Reinforced Polymer Matrix Composites

Aircraft undergoes various low-velocity impacts such as bird strike, runway debris, foreign tools drop, etc. on its structure. Kevlar is widely used in several components and structure of the aircraft as Kevlar is an organic fiber from an aromatic polyamide family. Carbon fiber has advantages like high stiffness and properties like that of kevlar. The present study focuses on the analysis of low-velocity impact properties of kevlar 149-carbon fiber reinforced polymer matrix composite material. In this analysis, kevlar 149-carbon fiber, pure kevlar 149 by 10 layers of laminate and pure carbon fiber by 10 layers of laminate are impacted by ball material with a mass of 8g at velocity of 9m/s. The ball impact on the laminate is simulated using LS-DYNA. The max. principal stress, absorbed energy, velocity and displacement of K149C, CK149, KK149CC, CCKK149, KK149 and CC are obtained and compared with all the six composite laminates. The composite laminate, K149C, proves to be the best laminate for aircrafts as it possesses a higher max. principal stress and lower displacement.

Effect of Different Fiber Reinforcements on Some Properties of Prosthetic Socket

In the perspective of environmental advance, significant attentiveness is being displayed in the usage of natural fibers like reinforcement in polymer composites. This paper focuses on building a prosthetic socket arranged from natural fiber-reinforced composite as an effort to substitute material currently accessible in the manufacturing of the socket. The vacuum bagging procedure was adopted to yield a below-knee socket. The laminates encompass woven flax, sisal, cotton, carbon, person, and glass fabric. The impact of diverse fiber layering sequences on some of the physical and mechanical characteristics was assessed. Laminated specimens were characterized by tests such as (hardness, surface roughness, density, water absorption). The results of this study showed that consuming altered forms of reinforcing materials had an abundant influence on the properties of prepared composite and the values of (hardness, surface roughness, and density) properties improved with increasing of the volume fraction of materials and the best composite specimens were three layers of flax with two layers of carbon fiber, were the hardness property ranges 86 MPa and density of (1.276 gm. /cm3) due to their exceptional mechanical properties. The results of the present study advocate that the arrangement of natural and synthetic reinforcements allows the preparation of bio-composites with enhanced performance.

The influence of stacking sequence on the low-velocity impact response and damping behavior of carbon and flax fabric reinforced hybrid composites

With the wide application of fiber reinforced polymer (FRP) composites, the impact resistance and damping properties of FRP have been considered as the essential properties of many applications. In this paper, the hybrid composites (FCFCF, where C represents carbon fiber layer and f represents flax layer) and sandwich structure (CFFFC) alternately laminated with carbon fiber and flax fabric were studied by vacuum-assisted resin pouring (VARI) process, and the effects of stacking sequence of carbon fiber and flax fabric layers on low-speed impact response and damping properties were studied. The better impact response and higher energy absorption of hybrid composites with the sandwich structure are attributed to the higher strength of the skin layer and better adhesion between core layers. Furthermore, affected by the types of surface fibers, FCFCF has lower vibration frequency and higher energy consumption, and its damping coefficient is 26.4% higher than that of CFFFC.

Numerical Study on the Energy Absorption and Damage Characteristics of Aluminum Alloy Carbon/Glass Fiber Laminates under Different Impact Velocities

To study the dynamic response of metal fiber laminates subjected to the same energy and different velocities, a finite element model of aluminum alloy-carbon/glass fiber laminates was constructed to analyze the impact dynamic response and discuss the characteristics of interlayer damage. The results show that under the same impact kinetic energy conditions, the higher the initial velocity of the bullet is, the faster the velocity decays during the impact, and the more kinetic energy is consumed overall. On the whole, the shape of the failure area of the metal layer is similar to the shape of the bullet plane, and the failure area of the fiber layer will extend along the direction of the fiber layer. Whether it is a carbon fiber layer or a glass fiber layer, the tensile failure area is larger than the compression failure area. The fiber tensile/compression failure area is the largest, followed by the tensile/compression delamination failure area, and the matrix tensile/compression failure area is the smallest. As the bullet velocity increases, the failure area of the glass fiber layer in different forms becomes smaller, while the failure area of the carbon fiber layer in different forms does not change significantly.

Macroscale assessment of low‐velocity impact on hybrid composite laminates

AbstractComposites are usually brittle materials and have low impact properties. Structural dimensions, stacking sequence, ply materials, ply thicknesses and ply angles are standard variables that influence composite‘s performance against impact loads. Stacking sequence in hybrid laminates affects the failure and impact resistance. Failure mechanisms at the low‐velocity impact of a rigid object in hybrid laminates are complex, and the subsurface damage in a composite laminate cannot be detected directly. However, various simulation platforms make it easy to see the impact damage between the plies of laminate. This paper numerically investigated the effect of stack sequence and hybridization of two fiber types against low‐velocity impact. The current study adopted four‐layer composite laminates of carbon and glass fiber layers with a stacking plan [C/C/C/C], [C/G/C/G] and [G/C/G/C], having lay‐up angles as [0°/45°/−45°/90°]. Keeping the impactor mass and the incident velocity constant, the laminates were subjected to low‐velocity impact. The damage contours for a failure mode were recorded and compared at the ply level. The numerical study resulted in impact imitations showing comparisons of the damage contours using Hashin failure criteria. Hybrid laminates display better performance in absorbing impact energies; however, hybrid laminates experienced more subsurface damage due to more impact energy absorption.

Mechanical Properties of Novel Reinforced Spray in Place Pipe Material With Potential Fully Structural Performance Application

Many utility owners in the United States are actively searching for new and innovative rehabilitation techniques to help them regain control and repair large tracts of their networks; moreover, traditional open cut replacement is too costly and slow to keep up with demand. Many trenchless techniques such as Spray-In-Place Pipe (SIPP) lining have been adopted by municipalities to renew their aging pipeline systems. The further development of SIPP linings could benefit the water community in the United States and around the world. SIPP lining could play a key role in controlling the future expected burden caused by the aging distribution networks. This study aimed to investigate the mechanical properties of a newly proposed reinforced spray in place pipe (SIPP) lining material that boasts structural characteristics. This material is a spray applied two component polyurethane high build coating. Three forms of sample were investigated during these tests: (1) No Fiber-Baseline (2) Rigid-with one layer of carbon fiber (3) Rigid—with two layers of carbon fiber. Three types of tests are performed: tensile, flexural, and hardness tests. This study included both experimental and Finite Element Analysis (FEA). Target mechanical properties of proposed material can be improved by using carbon fiber (CF) as reinforcement and based on the results of this study, the SIPP lining material with two layers of CF reinforcement has the highest value of 8,067 psi and 16,534 psi during the tensile and flexural test, respectively.

Effect of hygrothermal ageing on the mechanical performance of CFRP/AL single-lap joints

ABSTRACT Bonding technology presents several advantages over traditional mechanical connecting methods and, thus, has been widely used in the automotive industry. However, hygrothermal ageing environments may exert a significant degradation effect on the bonding structure during the service of the automobile. This study mainly investigated the effect of hygrothermal ageing on the quasi-static tensile strength of the adhesive layer of carbon fiber reinforced plastic (CFRP)-aluminium alloy (AL) single-lap joints (SLJs). A simple method, based on the finite element (FE) model, was used to determine moisture-dependent CZ properties. Numerical simulations of the quasi-static tensile properties of the CFRP/AL SLJs were also conducted, and the simulation results were consistent with the experimental findings. Results indicated that the failure strength of the adhesive and adhesively bonded CFRP/AL SLJs subjected to hygrothermal ageing declines with increasing ageing duration. Moreover, the degradation rate in the initial stages of ageing is significantly higher than that in later stages. Failure of the adhesively bonded CFRP/AL SLJs was characterised by cohesive failure and mixed failure. No carbon fiber delamination was observed in CFRP/AL SLJs following hygrothermal ageing.

Enhancement of the interlaminar fracture toughness and damping properties of carbon fiber reinforced composites using cellulose nanofiber interleaves

Cellulose nanofibers (CNFs), with excellent mechanical properties, could be obtained from plant fibers and prepared by the combined mechanical and chemical methods. Waterborne epoxy was used to reduce the hydrophilicity of CNFs before the CNFs films were prepared by freeze-drying and inserted between layers of carbon fiber reinforced polymer composites (CFRPs). The effects of CNFs content on the interlaminar fracture toughness and damping properties of CFRPs were investigated, and the lay-up sequences of CNFs interleaves on the loss factors of CFRPs were also examined. The results reveal that by the addition of 0.075 wt% and 0.05 wt% CNFs, the mode I and mode II interlaminar fracture toughness of CFRPs were improved by 22% and 25%, respectively. With the addition of 0.25 wt% CNFs, the loss factor of CFRPs was increased by 31%. However, the tensile and flexural properties of interleaved CFRP were only slightly decreased.

Investigation on Thrust and Torque Generation During Drilling of Hybrid Laminates Composite with Different Stacking Sequences Using Multiobjective Optimization Module

This paper highlights the reinforcement of two different fibers in the manufacturing of hybrid laminate composites. The feasibility of glass and carbon fiber-based hybrid composites is proposed for various high performances due to their versatile mechanical properties. However, anisotropic and non-homogeneity nature creates several machining challenges for manufacturers. It can be regulated through the selection of proper cutting conditions during the machining test. The effect of process constraints like spindle speed (rpm), feed rate (mm/min), and stacking sequences ([Formula: see text] was evaluated for the optimum value of thrust force and Torque during the drilling test. The cost-effective method of hand layup has been used to fabricate the composites. Four different hybrid composites were developed using different layers of carbon fiber and glass fiber layers. The outcomes of variables on machining performances were analyzed by variation of feed rate and speed to acquire the precise holes in the different configurations. The application potential of the proposed composites is evaluated through the machining (drilling) efficiency. The optimal condition for the drilling procedure was investigated using the multiobjective optimization-Grey relation analysis (MOO-GRA) approach. The findings of the confirmatory test show the feasibility of the MOO-GRA module in a machining environment for online and offline quality control.

Performance of Athletic Prosthetic Feet Made of Various Composite Materials with PMMA Matrix: Numerical and Theoretical Study

Prosthetic upgrades are specialized prosthetics that enable patients to participate in more demanding recreational activities, such as running. This study examines the use of prosthetic limbs, specifically the athletic prosthetic foot. The current research focused on the manufacturing and production properties of an samples athletic prosthetic Foot made from composite materials based on a polymethyl methacrylate resin (PMMA) reinforced with various fibers (UHMWPE, Perlon, Carbon fiber, and Glass fiber). The finite element method (ANSYS-19R) is used to build an athletic prosthetic model and apply boundary conditions to investigate the influence of deformation and stored energy on the performance of the sports prosthetic foot. Six laminates have been manufactured, and it has been discovered that adding a number of carbon fiber layers to UHMWPE has a better effect on deformation than adding a glass fiber 26% improvement. Furthermore, the findings show there is an improvement in performance when the number of classes was doubled, as the rate of improvement between the laminate to which carbon fibers were added was 31%, and between the laminate to which glass fibers were added by 32% under the same boundary conditions.

Simulation Analysis of Cam Wear in Shedding Mechanism of Loom

Aiming at the serious wear of the cam surface in the shedding mechanism of the loom weaving, which is likely to cause uneven movement of the heald frame, this paper proposes to add a layer of copper-plated carbon fiber composite material to the cam surface to improve the cam wear during the operation of the shedding mechanism. In finite element ABAQUS®, the cam is modeled, material properties and boundary loads are set, and ALE adaptive mesh technology and Umeshmotion subroutine are also used for wear analysis. The simulation results show that under the same conditions, the wear between the cam and the roller with a copper-plated carbon fiber layer is much smaller than the wear between the pure metal cam and the roller.

The Influence of CFRP Sheets on the Load-Bearing Capacity of the Glued Laminated Timber Beams under Bending Test.

Composite materials are increasingly used to strengthen existing structures or new load-bearing elements, also made of timber. In this paper, the effect of the number of layers of Carbon Fiber Reinforced Polymer (CFRP) on the load-bearing capacity and stiffness of Glued Laminated Timber beams was determined. Experimental research was performed on 32 elements—a series of eight unreinforced beams, and three series of eight reinforced beams: with one, three and five layers of laminate each. The beams with a cross-section of 38 mm × 80 mm and a length of 750 mm were subjected to the four-point bending test according to standard procedure. For each series, destructive force, deflection, mode of failure, and equivalent stiffness were determined. In addition, for the selected samples, X-ray computed tomography was performed before and after their destruction to define the quality of the interface between wood and composite. The results of the conducted tests and analyses showed that there was no clear relationship between the number of reinforcement layers and the load-bearing capacity of the beams and their stiffness. Unreinforced beams failed due to tension, while reinforced CFRP beams failed due to shear. Despite this, a higher energy of failure of composite-reinforced elements was demonstrated in relation to the reference beams.