Carbon Fiber Composite Materials Research Articles

Study and quantitative assessment of the structural inhomogeneities parameters of composite materials

The possibility of determining the size of the delamination region and the depth of its location in non-metallic multilayer weakly conductive materials using a unique pulsed eddy-current equipment by scanning the sample and registering the region of increasing amplitude of the differential signal has been practically confirmed. The nonstationary thermal and holographic interferometry method is used to obtain information on the shape and size of the bundles. For experimental testing, samples were used made of carbon fiber composite materials with artificially created defects in the structure of the material in the form of delaminations of various sizes and shapes.

DESAIN DAN SIMULASI SOCKET PROSTESIS BAWAH LUTUT DENGAN VARIASI MATERIAL BERBASIS KOMPOSIT

Each year, the number of disabled people in Indonesia increases. About 2.4 million people had some trouble walking in 2014. It includes 650,000 individuals who have significant difficulty walking and ascending stairs. Lower limb prostheses are an option for those who are unable to walk due to leg amputation. One of the most necessary parts of the below-knee prosthesis is the socket. Almost the local prosthetics socket did not give adequate information about the specification. It is a weakness of the local product because there is no guarantee of product safety. The lack of references and standards makes it difficult for manufacturers to improve their products to compete with imported products. This research is focused on the design and simulation of prosthesis sockets with various composite-based materials. The simulation method was adapted from ISO 10328 standard as the testing standard for prosthetics foot. The result shows that the sockets can be used for Indonesians with a calf circumference between 317-345 mm. The simulation results show that the suitable material for use is carbon fiber composite material with a thickness of 3 mm with a bolt hole of 6 mm.

Design and Heating Simulation of Continuous Laser Welding Curing Device for Carbon Fiber Composite Repair

Rapid repair of composite materials is a major challenge in composite applications. At present, the mainstream method is to use the heat repair instrument and the prefabricated patch bonding, but there are some problems, such as slow heating, uncontrolled temperature gradient and long curing time. Laser curing is a new type of carbon fiber composite material with fast curing time and good curing effect. The laser heating technology curing equipment designed in this paper consists of laser heating device, mobile device, rotating device, etc. The specific curing method is to use semiconductor fiber laser to cure the composite material when the laser and carbon fiber material are moving. Simulation software of laser heating process is simulated, and the resin base carbon fiber composite material as the research object, established three-dimensional physical model of laser heating carbon fiber composite materials, simulation and calculate the temperature field distribution in the laser heating process of carbon fiber composite materials and rule, a preliminary analysis of the laser parameters on the influence law of temperature of carbon fiber composite materials. As the laser power of the heating device laser increases, the average temperature and the maximum temperature achieved by the carbon fiber composite will be increased. With the acceleration of the laser moving speed of heating equipment, the maximum temperature that carbon fiber composite material can achieve will decrease, but the average temperature will rise in a certain range, which can have a certain insulation effect. The research results can provide certain reference for the temperature field simulation in the process of laser carbon fiber composite material.

Experimental Study During Electrical Discharge Machining of Reinforced Carbon Fiber Plastic Material

Abstract: The proper selection of machining conditions and machining parameter is an important aspect, before going to machine a carbon-fiber composite material by Die sinking electrical discharge machining (EDM). Because these conditions will determine such important characteristics as; Material removal rate (MRR), Electrode wears rate (EWR), and Surface roughness (R). The purpose of this work is to determine the optimal values of machining parameters of electrical discharge machine, while machining carbon-fiber-composite with copper electrode. The work has been based on the affect of four design factors: pulse current(Ip) supplied by power supply system of electrical discharge machine (EDM), pulse-on-time(TON), gap voltage(Vg) and duty cycle () on such characteristic like material removal rate (MRR), electrode wear rate(EWR), and surface roughness(Ra) on work-piece surface. This work has been done by means of the technique of design of experiment (DOE), which provides us to perform the above-mentioned analysis with small number of experiments. In this work, a L9 orthogonal array is used to design the experiment. The adequate selection of machining parameters is very important in manufacturing system, because these parameters determine the surface quality and dimensional accuracy of the manufactured part. The optimal setting of the parameters are determined through experiments planned, conducted and analyzed using the Taguchi method. It is found that material removal rate (MRR) reduces substantially, within the region of experimentation, if the parameters are set at their lowest values, while the parameters set at their highest values increases electrode wear rate (EWR). Keywords: EDM, Material removal rate, Surface roughness, Tool wear rate,

Evaluation of the Yield Strength of a Carbon Composite Material Prepared by Wet Lamination and Vacuum Bag Molding

To evaluate tensile strength of the carbon composite material we used method of static tensile test according to the STN EN ISO 6892-1:2010-01 standard. The material for the production samples from the composite material was carbon fabrics KORDCARBON 200g/m2 – Twill weave. KORDCARBON 160g/m2 – Plain weave reinforced with epoxy resin Letoxid PR220+hardener EM315. The carbon composite for the test was prepared by Hand lay-up technology and Vacuum Bag molding method. Orientation to the layer laying direction of the individual samples in the test composite material influences the mechanical properties of the carbon fiber composite material produced by Hand lay-up technology and VMB- Vacuum molding bag method.

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.

Preparation of SA–PA–LA/EG/CF CPCM and Its Application in Battery Thermal Management

To improve the heat dissipation efficiency of batteries, the eutectic mass ratios of each component in the ternary low-melting phase change material (PCM), consisting of stearic acid (SA), palmitic acid (PA), and lauric acid (LA), was explored in this study. Subsequently, based on the principle of high thermal conductivity and low leakage, SA–PA–LA/expanded graphite (EG)/carbon fiber (CF) composite phase change material (CPCM) was prepared. A novel double-layer CPCM, with different melting points, was designed for the battery-temperature control test. Lastly, the thermal management performance of non-CPCM, single-layer CPCM, and double-layer CPCM was compared via multi-condition charge and discharge experiments. When the mass ratio of SA to PA is close to 8:2, better eutectic state is achieved, whereas the eutectic mass ratio of the components of SA–PA–LA in ternary PCM is 29.6:7.4:63. SA–PA–LA/EG/CF CPCM formed by physical adsorption has better mechanical properties, thermal stability, and faster heat storage and heat release rate than PCM. When the CF content in SA–PA–LA/EG/CF CPCM is 5%, and the mass ratio of SA–PA–LA to EG is 91:9, the resulting SA–PA–LA/EG/CF CPCM has lower leakage rate and better thermal conductivity. The temperature control effect of single-layer paraffin wax (PW)/EG/CF CPCM is evident when compared to the no-CPCM condition. However, the double-layer CPCM (PW/EG/CF and SA–PA–LA/EG/CF CPCM) can further reduce the temperature rise of the battery, effectively control the temperature and temperature difference, and primarily maintain the battery in a lower temperature range during usage. After adding an aluminum honeycomb to the double-layer CPCM, the double-layer CPCM exhibited better thermal conductivity and mechanical properties. Moreover, the structure showed better battery temperature control performance, while meeting the temperature control requirements during the charging and discharging cycles of the battery.

Smooth Particle Hydrodynamics Birdstrike Analysis on Aircraft Wing Leading Edge

Aircraft wing leading edges subjected to simulated birdstrike impact was investigated using the finite element ANSYS Autodyn solver. The bird was modelled using a Smooth Particle Hydrodynamics (SPH) method. Two validation studies were conducted prior to the main investigation. The first simulated impact on aluminium panels of varying thicknesses and impact velocities with results compared to Cessna Aircraft Company test data and a study conducted using LS-Dyna. The second validation study was performed on a steel plate at various impact velocities with results compared to U.S. Naval Research Laboratory data and a LS-Dyna solution. Following the validation studies, bird impact was simulated on aluminium and carbon fibre composite wing skin leading edges. Various skin thicknesses were investigated at an impact velocity of 155m/s (300 knots). Leading edge displacement and stress results showed that the carbon fibre composite material had a greater resistance than the aluminium to withstanding the high-speed impact.

Machining Thin-walled 2 1/2 D Structure in a Novel Aluminium Carbon Fiber Composite Material by the Micro-Abrasive Waterjets – an experimental investigation

ABSTRACT Among the metal matrix composite (MMC) materials, aluminum carbon fiber reinforced (Al-CF) composites are suitable for thermal management applications in fields, such as space, automobiles, etc. However, the application of Al-CF composite material is limited due to manufacturing difficulties, such as brittleness, non-uniform dispersion of fibers, and failure under low loads being a soft material. Challenges further increase in the case of producing thin-walled structures and features with a high aspect ratio (e.g. 2D structures).In this study, an experimental investigation is carried out on the machinability of Al-CF composite material. The material response to AWJs is assessed by studying the kerf characteristics in through-cutting and analyzing the machined surface micrographs. From the results, it is observed that the kerf width and the erosion depth increase with the waterjet pressure (P) and abrasive mass flow rate (mf ), and decreased with the jet traverse rate (vf ). A minimum taper is obtained at low mf and low vf at an optimum P. The material removal rate is maximum at high P and mf at an optimum vf . Based on this understanding, fabrication of a thin-wall (2D) structure with small features in Al-CF composite material is demonstrated by micro-AWJs.

Study on wear characteristics of carbon fiber at needle end in prefabricated composite weaving

Abstract Carbon fiber composites are widely used in aerospace, military and other fields. Their tensile properties are mainly borne by interwoven carbon fibers, wear of carbon fiber seriously affects the mechanical properties of carbon fiber composite material. In the process of prefab weaving, the end of the weaving needles carrying the movement of the carbon fibers causes serious wear on the fibers. In order to study the effect of weaving needle parameters and process parameters on the wear of carbon fiber bundle, a friction and wear experimental device of carbon fiber bundle was made. According to the research results, the corresponding parameters were optimized to reduce the wear of the carbon fiber bundle during weaving. The wear of carbon fiber bundle modified by imidazoline surfactant was also studied. The effects of fiber tension, weaving angle and needle end angle on the wear of carbon fiber bundle were studied by the control variable method. The wear of carbon fiber bundle was characterized by image binarization, SEM scanning and residual fracture strength detection. The residual fracture strength of the optimized weaving needles was increased by 23.92%, the residual fracture strength of the modified carbon fiber bundle increased by 14.57% after needle end wear.

Performance index of isogrid structures: robotic filament winding carbon fiber reinforced polymer vs. titanium alloy

ABSTRACT The structures adopted in the aeronautic field should have three main characteristics: they must be strong, stiff, and light. These targets can be obtained by choosing high performance and low weight materials, as composite or titanium alloy, but also the wise design of the structure itself is important for enhancing the mechanical performances. The isogrid structures, that are composed of a lattice frame reinforcing a skin, represent a very interesting solution to fulfill the abovementioned requirements. In the present work, a comparative analysis of the structural performances of lattice-stiffened cylinders made of different materials was carried out. The studied parts were made of carbon fiber composite material or titanium alloy, while a FEM model was implemented and verified for this study. The cylinder made of composite material was produced through robotic filament winding, an innovative technology that allows the attainment of high-quality parts. It was found that the strength and the stiffness of the structures were almost the same for both the analyzed material, but very interesting results were determined by considering the weight of the different structures: the composite material one resulted to be the most performant since it had the highest specific performances.

Mechanical and durability characteristics of pervious concrete reinforced with mechanically recycled carbon fiber composite materials

Mechanical and durability characteristics of pervious concrete reinforced with mechanically recycled carbon fiber composite materials

THE UTILIZATION OF BAMBOO WASTE AS A NEW ALTERNATIVE MATERIAL IN THE AIRCRAFT FUSELAGE INTERIOR PANEL STRUCTURE

In the aircraft manufacturing industry, the strength and weight of the material is one of the important considerations in structural design. Composite material is a material composed of two or more forming materials, each of which has different mechanical properties. Aircraft structure in this era are 50 - 80% composed of glass or carbon fiber composite materials as reinforcement. Unfortunately, these fibers when recycled produce harmful CO gas, difficult to degrade naturally and cause itching when in contact with human skin. For this reason, environmentally friendly and strong fibers are needed to replace the role of glass or carbon fibers. Is a bamboo plant, which is abundant in Indonesia which is considered suitable as a substitute material. In this study, a mechanical test and descriptive analysis were carried out on the strength of the composite material with variations in the types of bamboo fibers apus, wulung, tutul and petung. These fibers are arranged with epoxy resin and hardener as a binding material (matrix). And each fiber will be arranged in 0 ° pattern to the matrix. Then each material with a different fiber type will be tested for tensile and bending to obtain the value of stress and strain that occurs at its maximum loading. And the result is the average tensile stress value (Mpa) composite material of apus bamboo is 75.95, wulung bamboo 49.92, petung bamboo 112.73, tutul bamboo 83.85. Then the average bending stress (Mpa) composite material of apus bamboo was 239.073, wulung bamboo 214.236, petung bamboo 249.67, tutul bamboo 272.79. With this result, bamboo fiber composites are considered to be able to replace the role of carbon or glass fibers, as an alternative composite material in some parts of the interior fuselage of aircraft panels. Keyword: Composites material, Matrix, Bamboo Fibers, Carbon and Glass Fibers, Stress and Strain.

Functional performance differences between carbon fiber and fiberglass prosthetic feet.

Persons with lower limb amputation require increased functionality. The largest category of feet for active individuals with a transtibial amputation is energy storage and return (ESR) feet. These feet are typically constructed of carbon fiber composite materials. Recently, a prosthetic foot composed of a fiberglass composite has emerged in the market. However, there are no comparative studies of these devices. Compare the biomechanical performance and prosthesis-related quality of life when using a fiberglass prosthetic foot design compared with traditional carbon fiber ESR designs. This is a repeated-measures randomized cross-over trial. Gait analysis was performed on 10 experienced male subjects with unilateral transtibial amputations (K-level III) while walking on level ground and a ramp. Patient-reported outcomes were collected using the Prosthesis Evaluation Questionnaire. Gait data demonstrated increased ankle dorsiflexion (P < .01), similar ankle moments (P = .07), and increased ankle power generation (P = .01) when using the fiberglass foot. The increased power generation occurred at the correct time in the gait cycle such that the timing and magnitude of peak knee flexion was unaffected (P > .19). The fiberglass foot had greater energy absorption during gait (P = .01) with no difference in energy return (P = .37). The subjects expressed improved prosthesis-related quality of life with the fiberglass foot (P = .01). The findings of this study demonstrate that the new ESR foot comprising a fiberglass material had better performance than traditional designs using a carbon fiber material.

Influence of fiber alignment on pseudoductility and microcracking in a cementitious carbon fiber composite material

This research examines the effect of fiber alignment on the performance of an exceptionally tough 3D-printable short carbon fiber reinforced cementitious composite material, the flexural strength of which can exceed 100 N/mm2. The material shows pseudoductility caused by strain-hardening and microcracking. An extrusion-based manufacturing process allows accurate control over the spatial alignment of the fibers’ orientation, since extrusion through a tight nozzle leads to nearly unidirectional alignment of the fibers with respect to the directional movement of the nozzle. Specimens were investigated using mechanical tests (flexural and tensile load), augmented by non-destructive methods such as X-ray 3D computed tomography and acoustic emission analysis to gain insight into the microstructure. Additionally, digital image correlation is used to visualize the microcracking process. X-ray CT confirms that about 70% of fibers show less than 10° deviation from the extrusion direction. Systematic variations of the fiber alignment with respect to the direction of tensile load show that carbon fibers enhance the flexural strength of the test specimens as long as their alignment angle does not deviate by more than 20° from the direction of the acting tensile stress. Acoustic emission analysis is capable of evaluating the spatiotemporal degradation behavior during loading and shows consistent results with the microstructural damage observed in CT scans. The strong connection of fiber alignment and flexural strength ties into a change from ductile to brittle failure caused by degradation on a microstructural level, as seen by complementary results acquired from the aforementioned methods of investigation.

Mechanical Behavior of a Carbon Fiber Composite Material Reinforced with Titanium Nickelide Wire

A composite material of a carbon fiber matrix and reinforcing elements in the form of a wire made of titanium nickelide (PC-SMA) has been studied. The obtained PC-SMA material demonstrated improved elastic and strength characteristics compared to those of traditional carbon fiber composite material upon static three-point bending tests.

Effective stiffness and thermal expansion of three-phase multifunctional polymer electrolyte coated carbon fibre composite materials

Multifunctional composites including polymer electrolyte coated carbon fibres and polymer matrix systems gained recent interest in light-weight design related research areas. Compared to classical fibre reinforced plastics, the interphase, made by electropolymerisation on the fibre surface, represents a new, third material phase. The coating serves as ion-conducting separator in structural batteries and as insulating layer in energy transmitting multifunctional composites. The importance of this study is related to the fact, that multifunctional applications, based on such composites, are exposed to temperature changes in many cases. The coating material, acting as thin interphase, shows a significant temperature dependant Young’s modulus, determining the overall macroscopic behaviour under thermal loads. The new influences on the effective elastic properties of the composite are determined in this work in a 3D microstructural simulation approach based on a unit cell geometry. For the first time, the resulting effective properties are discussed towards the state of research and future work. First, the effective elastic stiffness is computed by isothermal virtual material testing, applying unit strain modes on the unit cell. Second, a uniform temperature change is applied and the effective thermal expansion coefficients are computed. The results show that a change of stiffness in the coating domain has a great influence on the effective stiffness in the transversal isotropic plane. The effective thermal expansion of the composite is also highly sensitive to the thermal expansion behaviour of the coating phase. Main conclusions are drawn towards multiphysical material simulation: Influences of the coating material properties have to be taken into account to compute effective properties. In particular, it is necessary to include the temperature dependant stiffness and the coefficients of thermal expansion of the interphase, which affect effective properties significantly. A thermo-mechanic coupled microscale model is needed to represent in-situ properties of such composites for applications with heat exposure.

Application of new carbon fiber material in sports equipment

The application of a large number of carbon fiber composite materials in competitive sports improves the level of competitive sports and promotes the development of sports. Select the carbon fiber composite matrix to optimize the design of sports equipment structure, and obtain the optimal form, thickness and number of layers of reinforcement grid; based on the obtained information and number of layers of reinforcement grid, establish the finite element model of sports equipment reinforced plate, analyze the relationship between the stability of sports equipment reinforced plate and bending stiffness, obtain the optimal structure of stiffness in the design space of sports equipment, and complete the optimization of stiffness.

Application Strategy of Carbon Fiber Composite Materials in Bridge Reconstruction Project

Initially, the materials used in the process of bridge construction were mainly wood, stone, etc., and gradually the concrete, steel and other types of special materials currently in-use were developed. With the current vigorous development of science, technology and social economy in China, the development of bridge projects has also been accelerated to a large extent. In recent years, China has not only studied on how to strengthen the performance of concrete, steel and other materials in bridge projects, but also the performance of the recently developed smart, nano-, fibrous and other types of materials. This paper focuses on the application strategy of carbon fiber composite materials in bridge reconstruction projects to serve as a reference.

Thermal stresses in composite cylindrical lattices

Deployable spacecraft technology should be both lightweight and compact for storage while also being rigid and expansive once deployed. A new type of structure that can meet both of these requirements is the morphing cylindrical lattice. This multi-stable structure can morph from a compact stowed state, to a long and slender deployed beam. It comprises narrow strips of carbon fibre composite material, making it particularly suitable for deployable booms, solar arrays and antennae. While existing modelling techniques focus on predicting the stability of lattices using symmetrical laminates, current work extends upon state-of-the-art by including the effects of thermal strains and curvatures that arise in non-symmetrical laminates when cured at elevated temperatures. As non-symmetrical laminates cool during post-cure, thermal stresses increasingly develop due to the variation of in-plane thermal expansion coefficient through the thickness. The model developed in this work, includes thermal stress effects, allowing for the design of thermally actuating lattices. This model is verified through comparison with finite element analysis and experimental data, both of which show excellent agreement.