Fiber Composite Materials Research Articles

Influence of the Compression Molding Temperature on VOCs and Odors Produced from Natural Fiber Composite Materials

In the automotive sector, the use of nonwoven preforms consisting of natural and thermoplastic fibers processed by compression molding is well known to manufacture vehicle interior parts. Although these natural fiber composites (NFCs) have undeniable advantages (lightweight, good life cycle assessment, recyclability, etc.), the latter release volatile organic compounds (VOCs) and odors inside the vehicle interior, which remain obstacles to their wide deployment. In this study, the effect of the compressing molding temperature on the VOCs and odors released by the flax/PP nonwoven composites was examined by heating nonwoven preforms in a temperature range up to 240 °C. During the hot-pressing process, real-time and in situ monitoring of the composite materials’ core temperature has been carried out using a thermocouples sensor. A chemical approach based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography—mass spectrometry (GC-MS) was used for the VOCs analysis. The olfactory approach is based on the odor intensity scale rated by expert panelists trained in olfaction. The results demonstrate marked changes in the VOCs composition with temperature, thus making it possible to understand the changes in the NFCs odor intensity. The results allow for optimizing the molding temperature to obtain less odorous NFC materials.

Pengaruh Fraksi Volume Terhadap Kekuatan Tarik Pada Serat Resam Menggunakan Resin Polyester BQTN-EX

Along with the times, the technology of utilizing natural fiber composite materials has developed, including in the field of engineering materials. One of them is natural fiber. This resam plant is easy to get because it is used in almost all corners of Indonesia, including the Bangka Belitung province because it is easy to process, and has stem content and stem size. The purpose of this study was to determine the best value for the effect of volume fraction on the tensile test of resam fiber composite materials. This study used a volume fraction variant of 10%, 15% and 20% by immersion in NaOH for 30, 60 and 90 minutes. The highest average results were obtained from the tensile test obtained from the 15% volume fraction with 60 minutes of NaOH immersion and the lowest average values were obtained from the 15% volume fraction with 90 minutes of NaOH immersion. From the research results obtained, it was concluded that the average value and variance of the tensile strength of resam fiber was found at the level 2 immersion time factor, which was for 60 minutes and the level 2 volume fraction factor, which was 15%. volume fraction, the most optimal.

Uji Impact Material Komposit Campuran Serat Bambu Dan Pasir Besi Menggunakan Metode Hand Lay Up

A composite is one of the materials that is a mixture of two or more materials to form a third, more useful material. In this study, researchers chose bamboo fiber and iron sand as reinforcement for composite materials because the selection of bamboo fiber as a research material took into account the potential of bamboo fiber in Indonesia which is abundant and has not been utilized properly. The purpose of making bamboo fibrous composite materials aims to find a material that is lighter stronger and more elastic, can be developed into other products such as the manufacture of drone frames, aircraft bodies, brake pads. The method used is an experiment with making specimens using the hand lay up method and testing using impact testing and micro photo testing. Impact testing is used to determine the properties and characteristics of the material in the form of strength, hardness, and ductility of the material while for micro photos it is used to determine the bond of the material composition with the best impact test. The test standards used are ASTM D6110-10 with random fiber arrangement and ASTM D6110-04 with the arrangement of woven fibers, with variations in volume composition of bamboo fiber and iron sand particles. In the D6110-10 specimens, the best specimens were found in the variation with the most bamboo fibers, namely 35S10 P with an impact energy of 4.27 J and an impact price of 0.04 J / mm2, while the lowest variation was found in the most iron sand, namely 35P10S with an impact energy value of 2.26 J and an impact price of 0.02 J / mm2. In the D6110-04 specimen also showed the same characteristics as the ASTM D6110-10 specimen, the 30S30P variation or the composition of the most bamboo fibers had an impact energy value of 4.09 J while in the 10S10P variation it was only 1.47 J. Thus the more bamboo fibers will make the impact strength of the specimen higher.

Investigate the mechanical strength of laminated composite carbon fiber with different fiber orientations by numerically using finite element analysis

The main objective of this study is to investigate the effect of fiber orientation on the mechanical property of carbon fiber composite material under the tensile loading condition and the dynamic response analysis using finite element analysis. In composite material analysis, the lamina or ply level is considered a microscale, and the laminate level is considered a macroscale. In this work, the modeling of laminated carbon fiber composite material has been done in Ansys ACP. The lamina thickness of carbon fiber/epoxy is taken 0.5 mm and the fiber orientation is considered 0°, 30°, 45°, 70°, 90°, and the stacking sequence are [0°]12, [30°]12, [45°]12, [70°]12, [90°]12 which are considered as the unidirectional lamina. The static structure analysis has been accomplished to find out the von mises stress, total deformation, and equivalent elastic strain under the tensile loading conditions, and modal analysis is carried out to find out the natural frequency. From the simulation, this study shows that the 0° fiber orientation carbon fiber composite material has better mechanical strength compared to 30°, 45°, 70°, and 90° fiber orientation, and the natural frequency is maximum for 0° fiber orientation carbon fiber composite compared to other fiber orientations.

Concept of the defense material system for the security of Indonesian national armed personnel against threats

It is essential to have materials that can support armor systems for the application of body armor composed of anti-ballistic material from coated fibers in trials in order to defend military personnel with better ballistic performance who are lighter against growing threats and conflicts. to support defense-related ballistics. New materials used in personnel protection systems are the subject of this discussion. As ballistic shields, fiber composite materials are currently used due to their light weight and high flexibility. This essay also discusses a thorough analysis of mechanism performance and failure. This study's goal is to advance knowledge about composite material body armor that is covered with a soft spall liner material, which can be used as a model for lightweight, affordable, and safe designs for military troops in times of conflict.

Structural Analysis of Airplane Wing Using Composite and Natural Fiber Materials: A Survey

Abstract: Natural fiber-reinforced polymer-based composites are increasingly used in modern society due to their numerous benefits for uses in mechanical engineering. Polymer-based composite materials are widely employed in civil construction, automotive, aerospace, and many other industries due to their many benefits. Natural fibers can be used to create new, highperformance polymer materials because they are affordable, environmentally friendly, renewable, and partially and fully biodegradable. Examples of these fibers include EGR Glass R Glass, Carbon fiber, and S Glass, as well as kenaf, pineapple, sugarcane, hemp, oil palm, flax, and leaf. The purpose of this study is to explore the use of natural fibers and composites in the production of airplane wings, including mechanical characteristics, applications, and potential as well as problems and future demand for natural composite materials for engineering uses. A good 50% of the airspace's components are natural composites. Because natural composites have the ability to lower aircraft weight, they are currently being used to construct helicopters, military fighter aircraft, small and large civil transport aircraft, cockpits, satellites, launch vehicles, and missiles. Rudder, spoilers, LG doors, keel beam, airbrakes, elevators, turbine engine fan blades, propellers, rear bulkhead, wing ribs, main wings, interior fixtures, etc. Composites made of natural fibers are attractive and promising. The use of natural fiber-based composite materials is growing daily due to their strength and integrity. The natural fiber is a renewable, environmentally beneficial, and biodegradable raw material. Both its mechanical and thermal insulation qualities are strong in natural fiber. However, the loading placed on the natural fiber and its youthful modulus determines its strength In addition to discussing the benefits of natural fibers over other materials, this paper provides a description of the several types of natural fiber, their physical and mechanical properties, and their advantages.

Mechanical Characterization and Feasibility Analysis of Polymer Fiber Composite Material

Abstract: The most prevalent reinforcing component in composite materials is carbon fiber. However, obtaining the monofilament's performance metrics of carbon fiber is a challenging task. In this study, we have used PolyVinyl Chloride (PVC) sheets having low mechanical properties. Our goal is to improve the mechanical properties of PVC sheets with the wrapping of carbon fiber. The wrapping of carbon fiber is done by the Hand Lay up method. In this paper, we analyze and compare the mechanical properties of the sheet by using two, four and six layers of carbon fiber on PVC sheets . The main aim of this study is to enhance the mechanical properties of PVC sheets by increasing the number of layers of carbon fiber without replacing the sheet and without enhancing the overall cost.

Identification of micro‐failure processes of HDPE‐henequen fiber composite material by using acoustic emission monitoring: Effect of fiber surface modification

AbstractIt is well known that fiber‐matrix interface region is crucial to ensure an efficient stress transfer between matrix and reinforcement and that it controls the composite behavior when subjected to external loads. In this experimental study, micro‐damage mechanisms of HDPE/surface modified henequen fiber reinforced composites are investigated in tensile quasi‐static mode. Two essential parameters of the materials composition were taken as main indicators: fiber length and quality of the fiber matrix adhesion. Essential Work of Fracture theory (EWF) was applied on double edge notch tensile (DENT) specimen geometry. Acoustic Emission (AE) technique was coupled to composite samples to obtain the characteristics of stress waves signals to monitor in real time damage evolution and failure mechanisms detection. Results demonstrated the substantial effect of chemical bonds interaction in the interface area on the composite mechanical properties. The total fracture work (Wf) exhibited an increasing value in both components, We and Wp, in chemically treated fiber composites. Likewise, mechanical properties are reported to be higher by 37% in maximum load in such materials. Elastic waves detected by AE were identified and correlated to micromechanical events during composite damage sequence. Most of the signals corresponded to microcracks (signals of low amplitude, short duration), propagation of microcracks (signals of medium amplitude), fracture of fibers and matrix (signals of long duration and high amplitude). AE signals detected exhibiting higher energy were associated to an enhanced fiber/matrix interface.

A finite element analysis of load distribution during donning and orthostatic posture in the ITOP hybrid subischial socket.

Pressure and shear stresses applied to the stump of a transfemoral amputee wearing a newly designed prosthetic socket have been analyzed by a finite element modeling approach. The new socket was developed by the Istituto Tecnico Ortopedico Preneste, and it was named the "hybrid subischial socket." This work aimed at understanding the loads' distribution on the stump surface in 2 operative conditions: at the end of the wearing phase and during the orthostatic posture. The model of the stump was composed of 4 different materials: the femoral bone, the muscle tissue, the fat, and the skin layers. Except for the bone (rigid), the biological tissues were modeled as Neo-Hookean, and their mechanical properties were taken from the literature. The socket was composed of a containment frame, made of carbon fiber composite material, a shell made of flexible silicone, and a liner made of hyperelastic silicone. The results of our simulation show that the main support areas are located in a proper position, in agreement with the ideal principles of this prosthetic design, and the maximum pressures are well below the pain threshold reported in the literature for the same contact areas. We can conclude that although the upper rim of the socket is well below the ischiatic area, the new socket design allows for a safe and comfortable support of the body weight. This is in agreement with the evidence of a good functionality and acceptance of this prosthetics gathered in the many real applications.

Comparative study of the explosive blast resistance of metal and composite materials used in defence platforms

Naval ships, military aircraft and land defence platforms are mostly constructed using steel, aluminium alloy, carbon fibre composite and/or glass fibre composite materials. Defence platforms are at risk from shock wave loads generated by explosive events, and therefore it is imperative that the construction materials are resistant to blast-induced deformation and damage. A comparative assessment is presented into the dynamic deformation and damage of metals and composites representative of naval construction materials when subjected to explosive air blasts. Flat plates of equal thickness (4 mm) or plates of similar areal density (in the range 6.2–9.2 kg/m2) made of the four materials were subjected to explosive blasts. Experimental blast testing and finite element (FE) modelling revealed that when the plate thickness was the same (4 mm) then the steel experienced less deformation (by ∼50–60%) and plasticity than the aluminium alloy due to its higher mechanical properties. The steel and aluminium plates were more resistance to blast-induced deformation (by up to ∼260–320% and ∼130–145% respectively) than the composite materials of the same thickness (4 mm). However, when the materials are compared on similar areal density, which is critical for lightweight design, the blast performance of the composite materials was similar to aluminium alloy and superior to steel. Deformation of the steel was up to 50% higher than the other construction materials, with the percentage increase rising with blast impulse.

Potential of natural fiber composite materials for bulletproof vest applications

The bulletproof vest material that is often used is a composite material. Composites are a mixture of two or more material elements, with different mechanical properties, which aim to obtain new materials that have better mechanical properties than the constituent materials. One alternative mixture of materials in composite materials is to use natural fibers as a substitute for kevlar fibers. In Indonesia, which has a tropical climate, natural fibers are very easy to obtain from various kinds of plants found in Indonesia. Along with the many plants obtained, a lot of waste is also produced because of this. So research was conducted on the utilization of the potential of natural fibers for alternative composites. With the experimental method, from the results of the experiment, the results obtained from the five natural fibers that have been discussed, namely pineapple leaf fiber, water hyacinth fiber, bark fiber, hemp fiber, and bamboo fiber, only pineapple leaf fiber has not met the National Institute of Justice (NIJ) standard, while the other four natural fibers have met the NIJ standard for bulletproof vests.

Cracking and Fiber Debonding Identification of Concrete Deep Beams Reinforced with C-FRP Ropes against Shear Using a Real-Time Monitoring System.

Traditional methods for estimating structural deterioration are generally costly and inefficient. Recent studies have demonstrated that implementing a network of piezoelectric transducers mounted to critical regions of concrete structural members substantially increases the efficacy of the structural health monitoring (SHM) method. This study uses a recently developed electro-mechanical-admittance (EMA)-based SHM system for real-time damage diagnosis of carbon FRP (C-FRP) ropes installed as shear composite reinforcement in RC deep beams. The applied SHM technique uses the frequency response measurements of a network of piezoelectric lead zirconate titanate (PZT) patches. The proposed strengthening methods using C-FRP ropes as ETS and NSM shear reinforcement and the applied anchorage techniques significantly enhanced the strength and the overall performance of the examined beams. The retrofitted beams exhibited increased shear capacity and improved post-peak response with substantial ductility compared with the brittle failure of the non-strengthened specimens. The health condition and the potential debonding failure of the applied composite fiber material were also examined and quantified using the proposed SHM technique. Damage quantification of C-FRP ropes is achieved by comparing and assessing the values of several statistical damage indices. The experimental results demonstrated that the proposed monitoring system successfully diagnosed the region where the damage occurred by providing early warning of the forthcoming critical shear cracking of concrete and C-FRP rope debonding failures. Furthermore, the internal PZT transducers showed sound indications of the C-FRP rope's health condition, demonstrating a direct correlation with the mechanical performance of the fibers.

Thermo-physical and fire properties of sustainable bio composites: Experimental and computational analysis

ABSTRACT Bio-composites were prepared by incorporating broom grass, fishtail palm, sansevieria fibers as reinforcement in unsaturated polyester resin using hand lay-up method. The thermo physical and fire properties of bio-composites has been examined by varying the fiber content (0 to 39 wt. %) and temperature (30–120°C). The thermal insulation and heat storage capability of samples was assessed using guarded heat flow meter and differential scanning calorimeter. The experimental results reveal that, as the weight fraction of fiber increased, the insulation capability of composites increased, whereas it decreased with the temperature. The response of specific heat and thermal diffusivity of composites with temperature was analyzed. Temperature distribution and heat transfer through the composite materials was computed using ANSYS fluent solver. The rate of heat transfer through the fishtail palm fiber composite is 14.02% lesser than glass fiber composite. Cone calorimeter was used to measure fire behavior of the samples and the results reveal that the broom grass fiber composite material possesses better fire resistance characteristics against fire hazard. Morphological study of composites was performed with the help of Scanning Electron Microscopy (SEM) for the visualization of homogeneity of surfaces. Developed bio-composites are the potential materials to replace petrochemical-based products.

Ecofriendly panels for building with eucalyptus sawdust and vegetal polyurethane resin: A mechanical evaluation

The use of natural fibers in composite materials has become an alternative to use synthetic ones. With the increase in consumption and the generation of waste, it becomes interesting to search for alternatives friendly to environment. The objective of this work was to evaluate the mechanical properties of composites manufactured using residues: from the wood industry (eucalyptus sawdust), from red ceramic (chamotte), and a vegetable based resin (castor oil-based polyurethane resin) as a matrix. The composites were manufactured in volumetric fractions of 70, 75, 80 and 85 of eucalyptus sawdust; and 0%, 5% and 10% of chamotte, totaling 12 formulations. Scanning electron microscopy (SEM) analyzes were performed on the eucalyptus sawdust used and on the composites produced with and without chamotte. The results indicates that both for the modulus of elasticity and modulus of rupture, the increase in the volumetric fraction of chamotte incorporated at composites causes an increase of properties in all compositions studied. In perpendicular tensile testing, it obtained values between 1.910 and 3.449 MPa. In the izod impact testing, values between 47.61 and 115.44 J/m were obtained. It was observed on SEM images that with the incorporation of chamotte on composites there was a great reduction in the amount of bubbles and voids presented at polymeric matrix and in some compositions have increased also the mechanical properties. Thus bringing a new option for use and adding value to this residue from the ceramic industry, producing an ecofriendly composite panel.

Machine learning-based damage sensing and self-healing of carbon fiber/nylon composites via addressable conducting networks

In this work, addressable conducting network (ACN) was used for the damage sensing and self-healing of continuous carbon fiber reinforced nylon composite (CFRP). The machine-learning was used for accurate damage sensing by training the resistance change of composites along ACN due to their structural damage. Also, self-healing of the carbon fiber composite material was performed by applying the electrical current to generate local heating through the detected damage location. The self-healing conditions such as the current input pairs of ACN and amount of the electrical current were determined through the artificial neural network (ANN)-based machine-learning technique. As a result, high-accuracy damage sensing based on machine learning with ACN was conducted, and self-healing with a healing efficiency of 98% could be achieved.

Effects of The Addition of Carbon on Abaca Fiber and PVA Composite Materials Based on Mechanical and Acoustic Properties

Effects of The Addition of Carbon on Abaca Fiber and PVA Composite Materials Based on Mechanical and Acoustic Properties

Valorization of hemp fibers into biocomposites via one‐step pectin‐based green fabrication process

AbstractIn this paper, an environmentally friendly fabrication process was reported to valorize hemp fibers into biocomposites through a pectin‐based crosslinking reaction. In this water‐based chemical approach, the hemp fibers were crosslinked via a transesterification process between pectin and lignin present in hemp fibers to produce hemp fiber composites in a one‐step process. Our green process was advantageous over conventional processes that rely on the use of petroleum‐based organic solvents and high reaction temperatures because water was used as the reaction solvent with a mild reaction temperature (70°C). Additionally, to further optimize this biocomposite fabrication process, one‐factor analysis of variance study was carried out for investigating the main and interaction effects of the mass ratios of pectin to hemp fiber (1:5, 2:5, 3:5, 4:5, and 5:5) on the compressive strength and bulk density of the hemp fiber composite materials. In addition, the fabrication process was explored at different pH values to probe its versatility. The compressive strength of the as‐synthesized hemp fiber composite materials was observed to be dependent on the pH of the reaction conditions, indirectly confirming the formation of ester bonds between pectin and the lignin of hemp fibers via transesterification.

Study of the thermal and moisture aging effect on the residual mechanical properties of a structural composite material

The main aim of work is experimental research and description of the mechanical behavior regularities and strength properties degradation of a fibrous structural composite material under combined mechanical and thermal effects and aging in aggressive (operational) environments. Data on the various environments influence such as process water, seawater and machine oil at different durations (15, 30, 45 days) and temperatures (22°С, 60°С and 90°С) on the destruction processes of the composite and the realization of various mechanisms of damage accumulation on during quasi-static tests for interlayer shear. The paper presents the experimental data obtained by the acoustic emission technique. The results of a sample's microstructure study obtained using a stereo microscope before and after thermal and moisture aging in aggressive environments.

Study of the laminas’ stress-strain state for cross-ply composites with the [± 45°]2s lay-up: tensile tests

In this paper we have analysed the relations that allows one to determine the components of strains and stresses in the orthotropic axes of layered fiber reinforced composite materials in tensile and compression experiments for test specimens with the [±45°]2s lay-up. In particular, such relations were compiled on the assumption that in a cross-ply fiber composite two adjacent layers with the [±φ] lay-ups can be considered as one symmetrically reinforced layer with orthotropic properties. To establish the degree of accuracy of these relationships and assumptions, numerical experiments were carried out to determine the parameters of the stress-strain state of specimens consisting of two and four monolayers of a unidirectional fibrous composite material with the [±45°]2s lay-up. The analysis has been performed in the ANSYS finite element analysis program system in a linear formulation of two- and three-dimensional problems. It is shown that in the central zone of the specimen, the theoretical-experimental methodology based on the above mentioned relations has a sufficient degree of accuracy. Based on the analysis of results of three-dimensional problems, the formation of a linear torque in the specimen, which causes the twisting of some zones of the specimen along its length, has been revealed.

Production Technology of Ecological High Performance Fibre Composite Construction Materials

Eco materials derived from natural plant fibres and mineral binders are an alternative solution for modern ecological construction. This research is devoted to developing production technology for ecological high-performance fibre composite materials based on hemp shives and magnesium binder. The proposed composite wall structures consist of outer envelope layers made from dense hemp composite and middle insulation layer made from a lightweight hemp composite. The article describes the process of manufacturing a hemp composite boadr and the process of creating a three-layer structure of the outer wall. Used mix compositions are based on previously elaborated mix compositions based on magnesium oxychloride cement (MOC) binder and hemp shives. This study presents the case study of testing samples from hemp composite boards produced in actual industrial conditions. During an experiment, 20% magnesium oxide was replaced as an alternative binder, such as metakaolin and fly ash. The purpose of modifying the compositions of the composite is to increase the water resistance of the material and improvement of the hydraulic properties of the material, as it was previously found that this material is hygroscopic concerning the high humidity of the ambient air.