Fiber Composite Materials Research Articles

The drilling process impact on the parameters of the polymer composite materials processing quality

The paper examines the influence of the drilling process on the strength characteristics of fibrous polymer composite materials. Experimental studies of the polymer composite materials processing with spiral drills and cutting edges of P18 and VK8 with a diameter of 5 mm were conducted in cutting modes in accordance with the technological recommendations of TI 36-39-89 (SE "Antonov"). To analyze the temperature factor influence on the strength indicators of carbon fiber ELUR-P-01 and fiberglass T-10-14 in the drilling process, experiments were conducted in accordance with the ASTM-D5766 standard (USA). Temperature measurements during drilling were carried out with a non-contact infrared pyrometer DT-8865. Research on the ultimate strength of samples with holes was performed on the INSTROM - 5582 installation. It was established that the polymer composite materials strength of bolted joints working under compression is higher when processed with carbide drills with cutting edges with VK8, which can be explained by the fact that the tool made of carbide material promotes more intensive heat removal from the cutting zone and reduces the force load due to cutting edges of the drill.

Reinforced Epoxy Binder Modified with Borpolymer.

Polymer binders based on epoxy resins have unique properties that contribute to their use in many composite industries. The potential of using epoxy binders is due to their high elasticity and strength characteristics, thermal and chemical resistance, and resistance to climatic aging. This is the reason for the existing practical interest in modifying the composition of epoxy binders and understanding the strengthening mechanisms in order to form reinforced composite materials with a required set of properties based on them. This article presents the results of a study of the process of dissolving the modifying additive of polymethylene-p-triphenyl ether of boric acid in the components of an epoxyanhydride binder applicable to the production of fibrous composite materials. The temperature and time conditions for the dissolution of polymethylene-p-triphenyl ether of boric acid in anhydride-type isomethyltetrahydrophthalic anhydride hardeners are presented. It has been established that the complete dissolution of the borpolymer-modifying additive in iso-MTHPA occurs at a temperature of 55 ± 2 °C for 20 h. The effect of the modifying additive of polymethylene-p-triphenyl ether of boric acid on the strength properties and structure of the epoxyanhydride binder has been studied. Increases in transverse bending strength up to 190 MPa, elastic modulus up to 3200 MPa, tensile strength up to 0.8 MPa, and impact strength (Charpy) up to 5.1 kJ/m2 are observed when the content of the borpolymer-modifying additive in the composition of the epoxy binder is 0.50 mass. %.

Numerical analytical method of predicting the durability of fibrous composite materials under conditions of biaxial cyclic loading

A combined numerical-analytical method for predicting the durability of fibrous composite materials under conditions of biaxial cyclic loading is proposed. The model of nonlinear elastic behavior of random composites is used. The mechanics problem of determining the stress-strain state in the matrix and fibers is solved within the framework of the physically nonlinear theory of elasticity with the use of numerical methods. To predict the durability of an anisotropic composite in the macro volume, the matrices strengthening effect were used. The method of determining the equivalent stress used for asymmetric two-dimensional loading is considered. The influence of the average stress on the fatigue characteristics of the matrix with nonlinear strengthening is shown. Examples are given that illustrate the importance of the mutual influence of nonlinear elastic and anisotropic properties of the composite on the redistribution of stresses in the fibers and the matrix. As a practical result, we can note the possibility of predicting the long-term strength of the material when the field of cyclic stresses is determined in the vicinity of the inclusions. For a detailed analysis of local stress fields and specification of the type of complex load in structural elements, a numerical analysis was performed using finite element programs for a single, forming cell in the context of random homogenization.

Experimental Study on Seismic Performance of CFRP-Strengthened Recycled Concrete Columns with Different Levels of Seismic Damage

To study the strengthening effect of carbon fiber composite materials (CFRP) on recycled concrete columns subjected to different levels of seismic damage, four column specimens were designed for pseudo-static tests. The four specimens were categorized as non-destructive without strengthening (prototype), non-destructive strengthening, medium seismic damage strengthening, and severe seismic damage strengthening based on the replacement rate of recycled aggregates and the level of seismic damage. The characteristics of the deformation damage and seismic performance indicators of each specimen were compared and analyzed. The results were verified on the OpenSees platform. A decrease was observed in the initial stiffness of the seismically damaged recycled concrete column specimens strengthened with CFRP, while the ductility, peak bearing capacity, and energy dissipation capacity of the specimens were improved. In addition, with the reduction in seismic damage, the ductility and energy dissipation capacity of the strengthened seismically damaged recycled concrete column specimens were enhanced to different degrees. In particular, the cumulative energy dissipation of the strengthened specimens exposed to medium seismic damage increased most significantly, by 32.5%. In general, the hysteretic curves of the strengthened specimens were full, and the average ductility coefficients were 4.1–6.8. CFRP strengthening was more effective for restoring and enhancing the performance of the recycled concrete column specimens with medium and lower seismic damage levels (displacement ratio ≤ 3%).

Variationally consistent homogenisation of plates

Advanced fibre composite materials are often used for weight-efficient thin-walled designs, making a plate-based modelling approach suitable for their structural assessment. However, as the sub-structural geometrical features of these materials govern much of their behaviour, a multi-scale approach is necessary. A related challenge, however, is that the in-plane variation of these sub-structural features may be much larger than the total thickness of the material, whereby tailored homogenisation techniques for shell elements are needed. Existing frameworks for plate- and shell-based homogenisation are typically developed using second-order homogenisation in combination with the Hill–Mandel (macro-homogeneity) condition. However, it has been reported in the literature that this approach can lead to kinematic inconsistencies in the macro- to micro-scale transition. One inconsistency that is commonly reported, is the inability to correctly account for the macro-scale transverse shear behaviour on the sub-scale level. In this contribution, we show how the method of Variationally Consistent Homogenisation (VCH) can be used to develop a homogenisation framework for Reissner-Mindlin plate elements, which guarantees kinematically consistent prolongation and homogenisation operations. The homogenisation approach is demonstrated in four numerical examples, where it is shown that the method accurately homogenise the effective sectional plate stiffnesses of homogeneous and heterogeneous sub-structures.

Modeling of thermo-elastic properties of composite material in stability problems of multilayered shells

Thin-walled structures, the elements of which are plates and shells made of composite materials, are increasingly used in various industries. The growing needs of practice and the introduction of new composite materials require further improvement of the calculation methods of shell structures of inhomogeneous structure. Therefore, the problem of developing an adequate method of analyzing the behavior of shells made of composite materials with a multilayer structure is relevant. The work is devoted to the application of the developed method of finite elements for the analysis of geometrically nonlinear deformation and stability of elastic shells to the problem of the study of shells, the layer materials of which are composites of a fibrous structure. The method of structuring materials through the shell thickness and plan by using a universal 3D finite element is applied to model the thermoelastic properties of a ingomogeneous material. Determination of the effective characteristics of the composite material is realized by the structural micromechanical parameters of its components based on known methods of predicting elastic constants for this model of the composite material. The multilayer finite element, created within the framework of the developed approach, can be exploited to the problems of calculating thin elastic shells from both traditional and composite materials. The results of investigation of a multilayer composite panel using various micromechanical techniques are presented. The results of the study of a multilayer composite panel obtained by various micromechanical methods are given. These results are consistent with those obtained using the NASTRAN software. The new modification of the developed finite element makes it possible to analyze the stress-strain state and stability of multi-layer shells made of fibrous composite materials reliably, with accuracy acceptable for engineering calculations.

The Acoustic Performance of Natural Composites in Reducing Stress Levels: Textile Industry

The porous characteristics of recycled natural fibres make them suitable for use as acoustic materials. Straw and water hyacinth fibres are natural materials that can potentially be used as composites in damping devices. This study evaluated the acoustic performance of two types of reinforced composites containing natural fibers (water hyacinth and rice straw) and gypsum adhesives in reducing stress levels in the textile industry. The evaluation was carried out through laboratory tests using impedance tubes and direct testing in a textile factory to reduce the stress level of production machine workers and operators. Rice straw and water hyacinth fibres were thoroughly mixed in proven mass ratios of 10% and 30% with water and gypsum plaster as a binder. The mixture was pressed into a mould at a pressure of 3 MPa before being heated in an oven at 900ºC for 5 hours. Perforations measuring 4 to 8 mm in diameter were then made at equal distances on the panels. Acoustic panel performance tests were carried out with impedance tubes according to ISO 10534-2 standards at sound frequencies ranging from 0 to 6400 Hz. Field tests were also conducted at a textile factory, with each machine unit generating a sound source of 100 to 110 dB. Heart rate data was collected, and noise measurements were carried out before and after the panels were installed in the area around the operating machines. The results showed that the rice straw-gypsum composite with four perforations performed the best, achieving an α coefficient of 1.0 at a frequency of 1500 Hz and an NRC of 0.50, indicating effective noise reduction. The installation of acoustic panels around the noise source in the textile industry reduced noise levels by up to 9.8 dB and was found to affect workers' heart rates, indicating reduced stress levels. The questionnaire results also showed a significant effect on the stress levels of workers. The use of natural fibers in composite materials has the potential to be an eco-friendly and sustainable solution for soundproofing applications. Doi: 10.28991/CEJ-2023-09-06-02 Full Text: PDF

Moving adsorption belt system for continuous bioproduct recovery utilizing composite fibrous adsorbents.

A continuous protein recovery and purification system based on the true moving bed concept is presented. A novel adsorbent material, in the form of an elastic and robust woven fabric, served as a moving belt following the general designs observed in known belt conveyors. The composite fibrous material that forms the said woven fabric showed high protein binding capacity, reaching a static binding capacity equal to 107.3mg/g, as determined via isotherm experiments. Moreover, testing the same cation exchange fibrous material in a packed bed format resulted in excellent dynamic binding capacity values (54.5mg/g) even when operating at high flow rates (480cm/h). In a subsequent step, a benchtop prototype was designed, constructed, and tested. Results indicated that the moving belt system could recover a model protein (hen egg white lysozyme) with a productivity up to 0.5mg/cm2/h. Likewise, a monoclonal antibody was directly recovered from unclarified CHO_K1 cell line culture with high purity, as judged by SDS-PAGE, high purification factor (5.8), and in a single step, confirming the suitability and selectivity of the purification procedure.

Study on Tensile Performance of Double-Bolted Joints between Carbon Fiber Reinforced Polymer Plate and Aluminum Plate

Carbon fiber reinforced polymer (CFRP) with high specific strength, specific modulus, and other outstanding properties, which could be used in aerospace, shipbuilding, and railway. The joint of carbon fiber composite material plate and metal material plate plays an important role in the overall performance of the structure. In this paper, a carbon fiber reinforced polymer (CFRP) progressive damage model is developed based on composite laminate theory and 3D Hashian theory. The model of the double bolt single lap joint shear connection is established for the CFRP plate and the finite element method is used to carry out the stress analysis and failure prediction of the lap structure. The effect on structural performance under tensile conditions was studied through the change of double bolt spacing. The results show that the decrease in bolt row spacing can lead to the interference effect between holes. In addition, the progressive damage of the composite plate is located near the center line of the bolt hole.

Development and evaluation of mechanical properties of aluminium alloys and boron fiber composite material by powder metallurgy route

In recent year, aluminum alloy based metal matrix composites (MMC) are gaining in the field of aerospace and automotive industries, in order to improve by the advancement of modern technology, led to a rapid development of metal matrix composites. Properties can be tailored in the metal matrix composite as per the requirement for specific applications. In these composites the prime function of the fibers is that of supporting most of the applied load, while the role of the matrix is to bind the fibers together and to transmit and distribute the external loads to the individual filaments. Aluminum has been used matrix material owing of its excellent mechanical properties coupled with good formability. Addition of boron fiber as reinforcement inaluminum systemsimprovesthe mechanical propertiesof composites. In the present investigation Al-boron fiber composite was prepared by powder metallurgy route. Powder metallurgy homogeneously distributes the reinforcement in the matrix with no internal reaction and with less porosity. Boron fiber particles containing different weight fractions (5, 10 and 15 %) and mesh size (50 μm and 125 μm) are used as reinforcement. Though Al-boron fiber possess superior mechanical properties, the high abrasiveness of the boron fiber particles obstaclewiderapplication. The Mechanical Properties of Aluminum Alloy (AL2024) were assessed and the compression test was directedatthe material under tempered condition. Al-boron fiber composite has the widest application in the aerospace industry due to high hardness and light weight material. After the development of material that specimens were tested the under the optical, physical and mechanical properties.

Utilization of Cigarette Putt Waste as Reinforcement in Normal Fiber Composite Materials to Increase Tensile Strength

This study aims to examine the mechanical properties of fiberglass composites made from normal fiberglass and a mixture of cigarette waste. The research was conducted using three treatments, namely normal fiberglass, mixed fiberglass 1, and mixed fiberglass 2. The method used was experimental with one replication. The results showed that fiberglass mixed with cigarette waste has a lower maximum force value compared to normal fiberglass. Therefore, mixed fiber specimens with cigarette filter fiber mixed materials can be used as an alternative material to replace normal fibers.

Low temperature direct growth of carbon nanostructures on basalt fibers

Among natural fibers, basalt fibers have recently emerged as the main candidate to replace glass fibers in composite materials. Since the fiber/matrix interface strongly influences the final mechanical properties in a fiber reinforced composite, the current aim is to optimize the efficiency of the load transfer between the two different phases in the composite by growing carbon nanostructures (CNS), both nanofibers and nanotubes, on the surface of unsized basalt fibers exploiting less common catalysts compared to transition metals. Carbon nanostructures were grown onto unsized basalt fibers by chemical vapor deposition under different growth temperatures, using three different catalysts: copper, sodium, and iron. Considering the negative influence that high temperature has on the mechanical properties of basalt fibers, by lowering the synthesis temperature, we preserved the intrinsic properties of the basalt fibers, losing only 5% of the tensile strength at 300 °C growth temperature with a copper-based catalyst, while obtaining dense and uniform CNS growth. The different morphologies of the CNS obtained on the surface of the fibers were investigated by morphological and spectroscopic analyzes, while fiber/matrix adhesion was characterized by single fiber pull out tests, showing increases of 30% and 60% in interfacial shear strength and total pull out work, respectively. These less common catalysts provide an expanded design strategy for obtaining composites with improved interfacial bonding and multifunctional properties.

Effect of Processing Parameters on Bonding Performance of a Carbon Fiber/Polyetheretherketone Thermoplastic Composite Prepared by Induction Welding.

Among the various welding techniques used to bond thermoplastic composites, induction welding stands out as a fast, clean, and contact-free process that shortens the welding time and prevents the weight increase of mechanical fastening, such as rivets and bolts. In this study, we manufactured polyetheretherketone (PEEK)-resin-based thermoplastic carbon fiber (CF) composite materials at different automated fiber placement laser powers (3569, 4576, and 5034 W) and investigated their bonding and mechanical characteristics after induction welding. The quality of the composite was evaluating using various techniques, including optical microscopy, C-scanning, and mechanical strength measurements, and a thermal imaging camera was used to monitor the surface temperature of the specimen during its processing. The results revealed that the preparation conditions of the polymer/carbon fiber composites, such as the laser power and surface temperature, significantly affect the quality and performance of the induction-welding-bonded composites. A lower laser power during preparation resulted in weaker bonding between components of the composite and yielded samples with a lower shear stress.

Comparative study on properties of polypropylene-based composites reinforced with tobacco stalk fibers (unmodified / modified) from different parts of tobacco stalk

In this study, the effects of the three parts of the tobacco stalk: the xylem (TSX), husk (TSH), and core (TSC), on tobacco stalk fiber (TSF)/polypropylene (PP) composites were investigated. The effects of various types of interfacial modifiers and the number of recycled times on the properties of the composites were also explored. The results showed that the TSX reinforced PP composite exhibited better mechanical properties than those of TSH and TSC reinforced composites. The modifier improved the interfacial properties of the composites, and the tensile strengths of TSX/PP, TSH/PP and TSC/PP composites reached up to 32.8, 25.6 and 26.4 MPa in the presence of the modifier. The flexural strengths of TSX/PP, TSH/PP, and TSC/PP composites were 56.0, 46.1, and 48.7 MPa, respectively. Different parts of the tobacco stalk fiber had little effect on the thermal stability and crystallization properties of the compound material. After modification of the composites, their crystallization properties were improved, while there were no significant changes in their thermal stability. After four cycles of crushing and re-injection process, the composite material maintained good mechanical and thermal stability properties, and the interface of the compound material was tightly bonded, indicating that the prepared composites exhibited good reusability properties. Tobacco stalk fiber composite material can replace plastic or wood in decorative building materials, horticultural engineering materials, transportation packaging etc., which can obtain significant economic benefits by not only improving the broader utilization of agricultural and forestry waste but also reducing the use of plastics.

Characterization of Natural Cellulosic Fiber Obtained from the Flower Heads of Milk Thistle (Silybum marianum) as a Potential Polymer Reinforcement Material

ABSTRACT Natural fibers are being investigated as alternatives to synthetic fibers in composite materials. In this paper, the physical, chemical, thermal, and morphological characteristics of fibers derived from milk thistle flower heads were characterized as potential polymer reinforcement material using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The fibers were found to contain 42.9% cellulose, 21.2% hemicellulose, and a negligible lignin content. The fiber constituent functional groups were similar to those observed for other natural fibers. The crystallite size and the crystallinity index were found to be 2.23 nm and 84 ± 3%, respectively. The thermal stability of the fibers was found to be 220°C. The fibers start rapidly degrading above 290°C. Morphologically, the fibers appeared to have a nonporous surface with well-structured longitudinal parallel grooves. Cross sectionally, the fibers consisted of multiple hollow lumens interconnected with cell walls. The hollowed nature of the fibers explains the low value (0.33 ± 0.04 g mL−1) of their density. The tensile strength of the fibers was determined to be 22 ± 1 MPa. In conclusion, the fibers of the flower heads of milk thistle can be used as effective reinforcements in polymer matrices.

Fuel, cost, energy efficiency and CO2 emission performance of PCM integrated wood fiber composite phase change material at different climates

Wood fiber is a great potential supportive material for creating a new composite the phase change materials (PCM) due to its beneficial qualities, including high sorption competency, low density, enviro -friendliness, economic effectiveness, and chemical inertness. The main objective of this paper is to study the effect of using the wood fiber/eutectic mixture of stearic and capric acid on the fuel, cost, and carbon emission-saving potentials for various PCM cases. Which experiences a phase transition within the thermally pleasant temperature range of buildings, used for the building's thermal energy storing purposes and consumption cost saving. The energy performance analysis was carried out for buildings incorporated with stearic and capric acid eutectic mixture of PCM with wood fiber-based insulation material (INS) in different climate regions. The results showed that the largest energy-saving capacity belongs to PCM5. The energy saving reaches 52.7% for PCM5 for a thickness of 0.1 m. The PCM1, PCM2, PCM3, PCM4 can provide energy saving rates of 23.5%, 34.3%, 44.7% and 50.5%, respectively. INS-PCM5 can provide about 1.74-, 1.5-, and 1.33 times larger cost savings than INS in 2nd, 3rd, and 4th regions for all fuels. The payback period varies between 0.37 and 5.81 years regarding the fuel and Region. Finally, the results indicate that the proposed composite provided a promising energy-saving potential in building applications by reducing.

A new damage-based failure criterion for nonlinear behavior of fibrous composite materials

In the present paper, a novel combined damage-based failure criterion is being proposed for predicting failure stresses in unidirectional fibrous composite laminas or laminates having a nonlinear material behavior. The present model incorporates the effect of a quantitative damage factor on the final stresses at failure. This is achieved through a new term called the quantitative directional damage-index (QDD-I) which assesses the contribution and effectiveness of damage in each principal material direction on the present failure criterion. From the QDD-I, it is proved that the principal material-direction with a linear or nonlinear stress-strain behavior showed a quantitative damage response on the proposed failure criterion. In a composite lamina, the contribution of fiber-damage and matrix transverse-damage are proved to have minor effects on the failure criterion, while in-plane shear-damage has the major effect. In order to verify the suitability and applicability of the criterion, results are tested using various theoretical and experimental data available from the literature. Furthermore, the model is compared with other failure criteria under both uniaxial and biaxial loading cases from a worldwide comparison, which showed reasonable accuracy and good agreement. Three types of fibrous composite materials are used; Graphite/Epoxy 4617/Modmore-II, Carbon/Epoxy AS4/3501-6, and Boron/Epoxy Narmco 5505.

EXPERIMENTAL INVESTIGATION ON FLEXURAL STRENGTH AND FRACTURE TOUGHNESS OF HYBRID HEMP AND E-GLASS COMPOSITES

Natural fiber composite materials are grabbing the attention of industries due its eco-friendly and sustainability. These are effectively replacing many of metals and ceramic comprised components in termsof accessibility, cost, strength and weight. The study of a material to resist a load which is having cracks internally is the important parameter, this which internally describes the fracture toughness of a material. Understanding of flexural strength (bending strength) helps to avoid the internal de-lamination. In this research a composite specimen is prepared using a naturally available hemp fiber along with commercially available E-glass. Traditional hand layup fabrication method is used to prepare the composite specimens. Fracture test specimen is prepared according to ASTM E399 and the flexural (bending) specimen is developed according to ASTM D790. The fracture toughness of the hemp/E-glass composite has with stand a critical load of 1192N with a yield stress of 50MPa. The fracture toughness strength up to 11.77MPa can be with stand by the composite specimen. Fracture toughness increases with respect to the alignment. Orientation of fibers increases the strength. Bending strength resist by the composite laminate is about 4.8MPa and this will be decreased due the improper bonding between the layers. SEM test helps to identify the reasons for failure

A review of the use of giant reed (Arundo donax L.) in the biorefineries context

Abstract The massive availability of biomass generated by the common giant reed (Arundo donax L.) motivates the search for its possible industrial use for the generation of high added-value products through implementing a biorefinery approach. The literature demonstrates the potential of common cane to obtain different high-value compounds, such as levulinic acid, oligosaccharides, fermentable sugars, highly digestible fiber for animal feed, polyphenols, and natural fibers for composite materials, among others. The data shows the upward trend in Europe toward the generation of new green industries, grouped under the biorefinery concept. Therefore, this review summarizes the current knowledge on the use of Arundo to produce materials, fibers, and chemicals. Major environmental concerns related to this plant are also reviewed. Special attention has been paid to the potential use of Arundo to produce chemicals using green chemistry approaches, as a way to contribute to and advance the achievement of Sustainable Development Goals. Recommendations for future research are also outlined.

Studying carbon fiber composite phase change materials: Preparation method, thermal storage analysis and application of battery thermal management

Carbon fiber composite phase change material (PCM) can serve as an excellent material for thermal storage system. This work presents a new composite PCM prepared with two raw materials of KAl(SO4)2·12H2O (X) and Na2SO4·10H2O (Y), supporting materials activated carbon fibers (ACFs), and thermal conductivity agent nano carbon powder (C). The characterization results show that adding 1 wt% C can increase the thermal conductivity about 81.0 % of mixed materials (C, X, and Y) than that of mixed X, Y; Moreover, the addition of ACFs also increases the thermal conductivity by 130 %. DSC tests reveal that phase change temperatures of XY and CXY are respectively 36.47 °C and 35.67 °C, meantime the enthalpies are 220.84 J/g and 185.24 J/g, respectively. Thus, this new material is suitable for the lithium-ion battery thermal management system (BTMS) applying. The application results show that ACFs composited CXY (ACFs/CXY) tremendously cripples the battery's temperature rise rate after the melting point in comparison with no wrapping material, and the ACFs/CXY-based BTMS can effectively control the battery temperature below 60 °C for 1903 s at the high heating power of 6 W. The ACFs composite PCM has the advantages of low cost, simple preparation, and easy acquisition, which reduces the cost of energy storage system, and has remarkable capacity of temperature controlling.