Types Of Carbon Fibers Research Articles

Hygrothermal aging behavior of C/GFRP hybrid rod with bundle‐by‐bundle dispersion

AbstractFiber hybrid with bundle‐by‐bundle dispersion can achieve the high performance of composites, fully understand the hybrothermal resistance of hybrid composites is the key to prove the applications in engineering structures. In the present paper, the hygrothermal resistance performances of new type carbon and glass fiber reinforced epoxy based hybrid rod with bundle‐by‐bundle dispersion produced by pultrusion technology is investigated experimentally. The tests of water absorption and desorption, thermal and mechanical performances are performed to obtain the evolution rules of hygrothermal aging. As a result, the water absorption of hybrid rod confirms to the Fick's diffusion behavior, the serious relaxation of resin matrix and the interfacial debonding of fiber‐resin exposed at high temperature provide more diffusion space for water molecules. Long‐term hydrothermal aging results in the recoverable plasticization of resin matrix and irrecoverable interfacial debonding of fiber‐resin, which brings about the degradation of 6.7%–15.0% for short beam shear strength (SBSS) retention. In addition, the plasticization effect reduces the cross‐linking density of resin matrix, which leads to the degradation of 3.3%–15.6% for glass transition temperature (Tg) retention. The life prediction results show that degradation rate of SBSS is gradually slow down and reached to a stable retention of 85.5%.Highlights Relaxation of resin matrix and interfacial debonding accelerate the diffusion of water molecules. Plasticization and interfacial debonding lead to the degradation of short beam shear strength retention and glass transition temperature. Long‐term life prediction shows that short beam shear strength e retention is 85.5%.

Investigation of pull-out and mechanical performance of fibre reinforced concrete with recycled carbon fibres

This paper presents the pull-out bonding behaviour and mechanical performance of recycled carbon fibre (rCF) reinforced concrete based on the recent investigation of fibre reinforced concrete (FRC) with rCF recovered from pyrolysis. Single fibre pull-out tests have been carried out to identify the apparent interfacial shear strength of different types of rCF and virgin carbon fibre (vCF) to identify the fibre matrix connection. Furthermore, a series of tests have been carried out to identify the workability, compressive strength and tensile strength of FRC. Besides rCF, also vCF and steel fibre were used for fabrication of FRC test specimens. rCF have shown the same adhesion behaviour and strength like vCF. Furthermore, the use of unsized or acrylate-based sized rCF creates an adhesion between fibre and matrix material. During the pull-out tests, the failure does not occur as an adhesive crack between fibre and cement matrix, but as a cohesive crack in the cement matrix. The mechanical performance of FRC with rCF was compared with mortar and FRC with vCF and steel fibres. The results of compressive test conducted for FRC with vCF and rCF indicated that the influence of vCF and rCF on the compressive strength of FRC was insignificant. On the other hand, the results of tensile test conducted for FRC with vCF and rCF indicated that the tensile strength of FRC with rCF was at least 14.9% greater than that of FRC with vCF.

Mechanical study on hybrid joining type carbon fiber reinforced composite

Mechanical study on hybrid joining type carbon fiber reinforced composite

Can Two-Dimensional Correlation Spectroscopy (2D-COS) Indicate Biocompatible Material?

Carbon nanofibers are a new type of carbon materials. One of the methods of obtaining them is the carbonization of a polymer precursor. They are attractive in many areas, including medicine, due to the possibility of modifying their properties in a wide range. For example, the conditions of the carbonization process result in the creation of materials with designed structures and surface parameters. In the current work, the nanoprecursor was polyacrylonitrile (PAN) fibers. Two types of carbon fibers obtained by carbonization of the PAN precursor at 1000 °C were tested. The first electrospun carbon nanofibers (ESCNFs) were cytotoxic, while the second ESCNF-f were biocompatible after functionalization. The parameters obtained from Raman tests did not clearly discriminate between the tested materials. Multiwavelength Raman studies, analyzed using the two-dimensional correlation spectroscopy (2D-COS), treating the laser energy as an external disturbance, showed a difference between both fibrous structures. 2D-COS indicates that structures resembling graphite systems, devoid of disordered carbon forms, are nontoxic.

Schematic construction of carbon fiber tow microstructure models and their effect on tensile strength of carbon fiber tow/epoxy composites: Quantification of carbon fiber distribution, misalignment, and interlacing

Carbon fiber reinforced polymers (CFRPs) are increasingly being used in cutting-edge technologies, thus rendering accurate material characterization essential. However, the unexpected microstructures of carbon fiber (CF) tows, such as random fiber distribution, misalignment, and interlacing, degrade the mechanical properties of CFRPs and render them unpredictable. Hence, the microstructures of CF tows and their effect on the performance of CFRPs must be investigated.Herein, we propose a framework for quantifying the microstructural parameters of three types of T700 grade CF tows and investigate their effects on the tensile strengths of CF tows and CF tow-reinforced composites. CF cross sections are analyzed via microscopy to measure the fiber distribution and misalignment with respect to the location. A two-roll mill experiment is designed to evaluate fiber interlacing by compressing the CF tow in the thickness direction. The tensile strengths of CFs, CF tows, and CF tow-reinforced composites are measured, whereas their interfacial shear strengths are obtained via a micro-droplet test.Two CF tow microstructure models are proposed: the uniform distribution model with a low degree of fiber misalignment resulted in a higher tensile strength ratio of CF tow compared to the core-shell model, as well as a higher tensile strength of CF tow/epoxy composites. Results indicate that the microstructure of the CF tow significantly affects the properties of the composite materials. Therefore, utilizing the framework proposed herein as a tow design parameter is expected to fulfill the varying requirements of important properties in composite material design based on the application field.

Temperature distribution analysis of gap type conductors and carbon fiber composite core conductors based on finite element

Temperature distribution analysis of gap type conductors and carbon fiber composite core conductors based on finite element

Determination of the type of arched carbon fiber reinforced fastening of the preparatory opening for the conditions of the «Dniprovska» mine in weakly metamorphized rocks

The object of study is an arched carbon fiber-reinforced support of constant cross-section in a layered massif of weakly metamorphosed rocks. The article presents an analysis of the possible use of arched fiber-reinforced support of constant cross-section in a layered massif of weakly metamorphosed rocks for the conditions of the «Dniprovska» mine (Ukraine) around the preparatory opening. An analysis of the stability of mine openings in Western Donbas mines has shown that it is necessary to modernize the support system by introducing carbon fiber. The main reason for the low stability of the opening is the insufficient load-bearing capacity of the support, while its technical characteristics do not take into account the complex mining and geological conditions. The increase in stresses at mining depth is associated with impact safety, which is a serious problem during mining. Metal arch supports are deformable and have high rock loads and require a high level of energy absorption, i. e., to be very strong and flexible to withstand significant loads and avoid large displacements of the opening walls. Carbon fiber-reinforced plastic is able to ensure the stability of the fastening system and eliminate the existing disadvantages of typical metal arch fasteners, namely, high labour intensity, low production speed and high weight of the structure. In this article, the stress-strain state for the specified conditions and the carbon fiber-reinforced plastic arch support of constant cross-section was analyzed using the SolidWorks software product, taking into account the physical and mechanical properties of carbon fiber-reinforced plastic and layered rocks. Taking into account the results of laboratory tests of an equivalent layered array on a press made of PLA and carbon fiber, the dependence of deformations of the equivalent array with increasing load was established. The use of arched carbon fiber supports of various cross-sections can ensure the opening stability by reducing the intensity of stresses around its contour. On the basis of this study, a rational arched composite support of constant cross-section was proposed for the conditions of the «Dniprovska» mine. The obtained results indicate the need for further research, which will be considered in the author's future works.

The influence of multi-scale tough liquid fiber toughening agent on the mechanical properties of oil well cement-based composite materials

Cementing is a key process in drilling engineering, and the cement sheath in cementing can sometime have problems such as significant brittleness, low toughness, and low resistance to impact damage, especially in perforation and fracturing environments where the cement sheath is more susceptible to damage. In response to the above issues, three types of inorganic carbon fibers, including 1 mm carbon fiber, 2 mm carbon fiber, and nanocarbon fiber, were studied indoors to investigate the influence of their ratios on the mechanical properties of cement paste. The optimal mixture of 1 mm carbon fiber, 2 mm carbon fiber, and nanocarbon fiber in a ratio of 3:2:1 was selected, and a multi-scale liquid fiber toughening agent BS-54 was obtained through special liquefaction process treatment. The liquid fiber toughening agent BS-54 has good water dispersibility and can evenly disperse in the slurry water, effectively improving the dispersion and addition of multi-scale fibers in cement slurry. The cement slurry prepared with multi-scale dispersed liquid fiber toughening agent has good rheological properties, water loss, and thickening properties. The addition of multi-scale dispersed liquid fiber toughening agent to cement slurry significantly increases the tensile strength, impact strength, and compressive strength of cement paste, effectively reduces the elastic modulus of cement paste, improves the strength of cement paste, and achieves toughening effect. Microscopic analysis shows that the active nanoparticles dispersed by multi-scale dispersed liquid fiber toughening agents can interweave between gaps, and the dense cross-linked structure formed by their multi-scale micro nano structure improves the toughness and strength of cement slurry. Moreover, the multi-scale dispersed liquid fiber toughening agent cement slurry ensures that the cement stone sample has good integrity under external impact, which is conducive to improving the impact resistance of the cement stone.

3D composite printing: study of carbon fiber incorporation to different construction thermoplastic matrices in regard to dilatation characteristics

PurposeThe purpose of this paper is to clarify the relationship between the use of different polymer matrices for the preparation of composite materials, namely, polyethylene terephthalate-glycol (PET-G) and polyamide (PA), using Composite Fiber Co-Extrusion technology with the application of two types of carbon fibers, short and continuous. The aim of the study is also to extend the knowledge of the production of composite materials with a defined structure from the point of view of their influence on the microstructure and their physical-mechanical properties.Design/methodology/approachAs part of the experiment, four types of samples were prepared, namely, two types of samples with PA polymer matrix and two types with PET-G polymer matrix. All types contained short carbon fibers and always one set from each polymer matrix in addition to continuous carbon fibers. All types were prepared using the same 3D printing parameters to avoid any further influence. The samples were then tested for microstructure using microCT, mechanical properties using a tensile test and dilatation characteristics from the point of view of aerospace applications. Finally, the raw materials themselves were tested.FindingsThe paper provides insight into the influence of polymer matrix types on the physico-mechanical properties of 3D printed composites. The analysis confirmed that the physico-mechanical results varied with respect to the interface between the polymer matrix and the carbon fiber. The implications of the conclusions can be extended to the development of products in the aerospace and automotive sectors.Originality/valueThis study provides information for composite applications in the aerospace industry, focusing on evaluating dilatation characteristics within very low temperatures (−60 °C) when using carbon fibers (continuous carbon fibers, short carbon fibers and a combination of both) in two types of thermoplastic matrices. This perspective on materials characterisation for aerospace applications is a very important and unpublished approach within the 3D printing of composites. These characteristics are important parameters in the design of prototypes and functional samples with regard to the resulting behaviour in real conditions.

Carbon Fiber and Its Composites: Synthesis, Properties, Applications

Carbon fiber is often preferred in composite production as it is a light and strong material. Traditionally, it can produce based on Polyacrylonitrile (PAN) and Pitch. Today, biomass-based carbon fiber production has studied as an alternative to these petroleum-based initiators. For this purpose, cotton, wood, and cellulose are the most used biomass types. However, environment-friendly carbon fiber does not yet possess as good tensile strength as petroleum-based ones. So, researchers added PAN during the production of bio-based carbon fiber. Carbon fiber can be made as a composite with many materials like polymers, metals, ceramics, and cement. It has a wide range of uses. Nowadays, researchers have studied to heal the interface between epoxy and carbon fiber to increase the functional properties of the composite. By preparing carbon fiber-reinforced metal, it can be possible to use composite as a catalyst. Carbon fiber is used as filler in concrete production to avoid crack formation. It is a crucial property for a material to prevent earthquake disasters. In brief, one can enable comprehensive and contemporary information about the synthesis and applications of all types of carbon fibers (PAN, Pitch, bio-based) and their composites (polymer, metal, ceramic, concrete, carbon nanotube, and graphene).

Investigation of the energy absorption behavior and damage mechanisms of aramid/carbon/jute fiber hybrid epoxy composites

AbstractToday, various fiber reinforcements are used in automotive, aerospace and defense industries. Many of these fibers are synthetic structures, which can cause problems such as environmental pollution and high manufacturing costs. Researchers have turned to the use of more environmental‐friendly and cost‐effective natural materials to minimize these problems. In this study energy absorption properties of the fiber laminate‐hybrid epoxy composites were investigated with dynamic loadings. Fiber type and hybridization effects were investigated under drop weight impact tests with 10, 20, 30 and 50 Joule impact energies. Besides, mechanical characteristics were examined via quasi‐static bending tests. In this context, double and triple fiber reinforced natural/synthetic and synthetic/synthetic hybrid composites were manufactured as sandwich type. Furthermore, it is also aimed an evaluation of using natural fibers in ballistic activities with this study. Fiber materials consist of woven type carbon, aramid and jute fibers. Hybrid composites were manufactured with the aim of providing mechanical optimization between the fibers and enabling the fiber layers to absorb more impact energy. In addition, performance evaluation was made by comparing natural/synthetic reinforced hybrid composites with full synthetic hybrid composites. The results show that significant improvements were achieved in bending and impact resistance of the composites by using jute fibers to the inner layers.Highlights Drop weight impact tests were carried out to determine the energy absorption behavior of the hybrid composites. Fiber type is effective in the mechanical behavior of the composite materials. Natural hybrid composites show well enough mechanical properties as well as low cost.

Study on heat-treated pyrolytic carbon deposited from methane on directly heated carbon fibres

The study investigated the morphology, microstructure, structure, texture, and mechanical properties of heat-treated at 1600 °C and 2000 °C pyrolytic carbon (PyC) deposited from methane using various methods such as scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Raman spectroscopy, and ultrasonic dynamic measurements of Young's modulus. The PyC was synthesised at 1100 °C using a chemical vapour deposition (CVD) method with direct electrical heating of the two types of carbon fibres (CFs). The results showed that the PyC had a low- and medium-texture (LT and MT PyC). Analysis of the graphitization trajectory allowed the determination of structural changes in the material as a function of temperature, including the growth of crystallites and an increase in the crystallinity proportion without the significant rearrangement within PyC. The crystallite size and the number of interstitial defects has increased with temperature that controlled mechanical properties. Therefore, based on the results obtained, the most suitable composites for further research in the context of electrodes for stimulation of nervous tissue were obtained at the temperature of their synthesis, i.e. at 1100 °C.

Damage evolution of CFRP laminates by normal and oblique impact erosion of pulsating water jets

Impact direction is one of the critical factors affecting the waterdrop erosion behavior of materials. In this paper, rain erosion damage behavior of a typical carbon fiber reinforced polymer (CFRP) laminate is investigated as a function of the impingement angle (0° as normal impact and 15°, 30°, 45° as oblique impact deviated from the normal) and the relative fiber orientation (parallel PA and perpendicular PE to the fiber direction of the surface layer) under the waterjet velocity of 320 m/s and the impact frequency of 50 Hz via a pulsating waterjet erosion test rig. After continuous impact of multiple waterjets, the typical damage of CFRP laminates is mainly composed of the central erosion crater and the upheaval of the surrounding surface layer. The onset and evolution of damage are mainly driven by the shear action of lateral jetting and stress concentration of hydraulic penetration exerted at the surface irregularities. There is no significant difference in the damage modes between the normal and oblique impacts, except for the asymmetric distributions of matrix cracking in PA-orientation and delamination in PE-orientation caused by the angle inclination. With the impingement angle increasing, the volume loss and erosion depth decrease while the incubation period increases mainly due to the decreases of water hammer pressure and contact area. The PA-orientation can cause lower incubation period and larger erosion mass loss than PE-orientation before the surface ply is penetrated, with the underlying mechanism related to the distinct tensile properties of CFRP laminates along longitudinal and transversal directions and the asymmetric properties of fiber–matrix interface. According to the fitting results of erosion curves, it is possible to describe the incubation period and the erosion rate of CFRP laminates under oblique impact using a two-branch equation, and Springer model can give reasonable prediction for the average incubation period and PA-orientation erosion rate of a certain oblique impact occasion with known 0° impact erosion results.

Multiscale analysis of composite pressure vessel structures wound with different fiber tensile force

The aim of this paper is the multiscale investigation of composite pressure vessel structures wound with varying fibre tension. The paper explores the potential of ”programming” the fibre tension force during the winding process of a high pressure hydrogen storage vessel. Two series of vessels were wound with two different tensions: Two series of vessels wound with forces of 3 N and 80 N respectively were experimentally investigated. Other technological factors, such as the type and weight of carbon fibre used, were kept constant throughout the study. Quasi-static burst tests were used to measure the elastic deformation of the vessel surface. Microscopic studies were also carried out to analyse the structure of the composite at different length scales. The fibre content, the geometric parameters of the voids and the distribution of the three main components of the composite – carbon fibre, technological defects and resin – were also determined. Representative RVE elementary cells were generated for both materials using statistical modelling. The composite was then homogenised and elasticity matrices were obtained for the fibre tensile forces in both materials.

Specific fractionation of ginsenosides based on activated carbon fibers and online fast screening of ginseng extract by mass spectrometry

Ginseng is beneficial in the prevention of many diseases and provides benefits for proper growth and development owing to the presence of various useful bioactive substances of diverse chemical heterogeneity (e.g., triterpenoid saponins, polysaccharides, volatile oils, and amino acids). As a result, understanding the therapeutic advantages of ginseng requires an in-depth compositional evaluation employing a simple and rapid analytical technique.In this work, three types of surface-activated carbon fibers (ACFs) were prepared by gas-phase oxidation, strong acid treatment, and Plasma treatment to obtain CO2-ACFs, acidified-ACFs, and plasma-ACFs, respectively. Three prepared ACFs were compared in terms of their physicochemical characterization (i.e., surface roughness and functional groups). A separation system was built using a column with modified ACFs, followed by mass spectrometry detection to investigate and determine substances of different polarities. Among the three columns, CO2-ACFs showed the optimum separation effect. 13 strong polar compounds (12 amino acids and1 oligosaccharide) and 15 lesser polar compounds (ginsenosides) were separated and identified successfully within 4 min in the ginseng sample. The data obtained by CO2-ACFs-TOF-MS/MS and UHPLC-TOF-MS/MS were compared. Our approach was found to be faster (4 min vs. 36 min) and greener, requiring much less solvent (1 mL vs. 10.8 mL), and power (0.06 vs. 0.6 kWh). The developed methodology can provide a faster, eco-friendly, and more reliable tool for the high-throughput screening of complex natural matrices and the simultaneous evaluation of several compounds in diverse samples.

Self-supporting multi-channel Janus carbon fibers: A new strategy to achieve an efficient bifunctional electrocatalyst for overall water splitting

A new type of self-supporting multi-channel Janus carbon fibers with efficient water splitting has been successfully manufactured using a specially designed parallel spinneret through electrospinning technology and subsequent carbonization technique. Every single Janus fiber composes of a half side of Mo2C and the other half side of Ni components as Mo2C, Ni embedded in N-doped multi-channel Janus carbon fibers ([Mo2C/C]//[Ni/C]-NMCFs) for overall water splitting. Under optimized condition, the hydrogen evolution reaction overpotential of [Mo2C/C]//[Ni/C]-NMCFs (62 mV) is just 24 mV higher than 20 wt% Pt/C (38 mV) at a current density of 10 mA cm−2. Furthermore, it achieves current density of 10 mA cm−2 to require an overpotential of 324 mV for oxygen evolution reaction. Additionally, the cell assembled by the identical [Mo2C/C]//[Ni/C]-NMCFs catalyst as both the cathode and anode needs only 1.607 V at a current density of 10 mA cm−2, which is only 0.022 V higher than that of Pt/C-IrO2 electrodes. Moreover, [Mo2C/C]//[Ni/C]-NMCFs catalyst also exhibits a long-term stability. The synergistic effect and unique heterostructure of Mo2C and Ni enhance the catalytic activity.

Chemical recovery of carbon fibers from composites via plasma assisted solvolysis

In this work plasma assisted solvolysis using nitric acid is proposed for chemical recovery of carbon fibers from carbon fiber-reinforced epoxy resin composites (CFRCs). Complete decomposition of the epoxy matrix could be achieved, regardless the composites’ geometry. The efficiency of the process was examined in terms of a) process duration, b) resin decomposition rate and c) materials properties. SEM and EDX data showed that the recovered fiber surfaces are almost free of epoxy resin residuals and their tensile strength was comparable to that of typical virgin carbon fiber. The process decomposition efficiency is very high without requiring additional organic solvents or high temperature / pressure, stressing the potential of this method for viable recycling of CFRCs.

Сравнительный анализ термоупругих характеристик керамоматричных композиционных материалов, определенных по различным модельным представлениям структурно фазового состава матричного материала

A comparative analysis of thermoelastic characteristics of ceramic matrix composite materials (CMC) obtained by liquid and gas phase technologies, reinforced with two types of carbon fibers (CF), is carried out based on different model structural phase composition of the obtained matrix material. It is noted that when implementing the liquid phase siliconizing and using high modulus carbon fibers with high negative values of the absolute value of the coefficients of linear thermal expansion (CLTE), a simplified model of the matrix material consisting of only one SiC phase can be correctly used. When implementing PIP and CVI technologies, CMC with low modulus CF and CF with low negative CLTE values show the greatest sensitivity to an increase in matrix porosity. For CMC based on CF T800, the change in the longitudinal CLTE was about 66% with a porosity of 20%. An increase in porosity leads to a decrease in all elastic characteristics of the CMC, to the greatest extent for the transverse modulus of elasticity and the shear modulus.

Atomistically informed hierarchical modeling for revisiting the constituent structures from heredity and nano-micro mechanics of sheath-core carbon fiber.

To better understand the heterogeneous anisotropic nanocomposite features and provide reliable underlying constitutive parameters of carbon fiber for continuum-level simulations, hierarchical modeling approaches combining quantum chemistry, molecular dynamics, numerical and analytical micromechanics are employed for studying the structure-performance relationships of the precursor-inherited sheath-core carbon fiber layers. A robust debonding force field is derived from energy matching protocols, including bond dissociation enthalpy calculations and rigid-constraint potential energy surface scan. Logistic long range bond stretching curves with exponential parameters and shifted force vdW curves are designed to diminish energy perturbations. The pseudo-crystalline microstructure is proposed and validated using virtual wide angle X-ray diffraction patterns and bond-orientational order parameters. The distribution or alignment features of the nanocomposite microstructures are collected from quantum chemical topology analysis and normal vector extractions. Non-equilibrium tensile loading simulation predicts the decomposed strain energy contributions, principal-axis modulus, strength limit, localized stress, and fracture morphologies of the model. Finally, an atomistically-informed stiffness prediction model combining numerical homogenization and analytical self-consistent Eshelby-Mori-Tanaka-type effective mean field micromechanics theory is proposed, giving a successful estimation of the overall stiffness matrix of the sheath-core carbon fiber system. The hierarchical models in combination with the carbonization reaction template will help in providing efficient and feasible schemes for the synergistic process-performance control of distinct types of carbon fiber.

Preparation and performance study of a novel conductive geopolymer

A novel conductive geopolymer (GP) based on fly ash (FA) and modified by carbon fiber (CF) was successfully developed in this study. Detailed investigations were conducted on various factors influencing resistivity, such as the type and content of CF, liquid-solid ratio, modulus of alkali activator, and the material’s sensitivity to temperature, pressure, moisture. The research findings highlight that short-cut CF enhances both the electrical conductivity and mechanical properties of GP, along with its sensitivity. Specifically, at an FA and short-cut CF mass fraction of 80% and 1.0% respectively, the resistivity and compressive strength of GP reached 5.58 Ω·m and 51.20 MPa, representing a 99.95% reduction in resistivity and a 40.66% increase in strength compared to pure GP. Additionally, the introduction of CF1 into the modified GP exhibited significant negative temperature coefficient and piezoresistive effects. Furthermore, FA not only enhanced the conductivity but also improved its water resistance of GP. This study provides a creative opportunity for design and fabrication of novel conductive intelligent GP materials.