Papers by Keyword: Carbon Fiber

Abstract: In today's changing times, more and more people will use automobiles to get around, and this will consume a lot of natural resources to supply cars, in order to make energy efficiency, reducing the overall weight of the automobile is a direct way to reduce the weight of the automobile, and we need to use materials that can make the weight lighter while maintaining a certain level of strength. This review paper explores the properties of five custom materials: aluminum alloys, magnesium alloys, titanium alloys, carbon fiber, and ceramics. By comparing specific strengths and fatigue resistance, researchers found that customizing aluminum alloy are the most suitable materials for improving energy efficiency and reducing total vehicle weight, while still maintaining a certain level of stiffness. According to the data on the specific strength and fatigue resistance of aluminum alloy, it reaches conclusion that custom aluminum alloys can be used in the design of automotive vehicles as a function of improving fuel efficiency by reducing weight.

Abstract: This study investigated the potential of biodegradable polymer composites for e-scooter chassis applications in response to the growing demand for sustainable materials. Four composites were tested: two carbon fiber-based (10H and 4H), one fiberglass-based, and one linen (flax)-based. The mechanical properties evaluated included tensile strength, flexural strength, modulus of elasticity, and impact resistance. The results showed that carbon fiber composites (10H and 4H) demonstrated tensile strengths of 2900 MPa and 2860 MPa, respectively, while the flax composite achieved a tensile strength of 940 MPa. The fiberglass composite exhibited the highest flexural strength at 2200 MPa, followed by the carbon 10H composite at 1690 MPa and the flax composite at 1300 MPa. Impact resistance ranged from 90 kJ/m² for the fiberglass composite to 75 kJ/m² for the flax composite. The modulus of elasticity was highest in the carbon 10H composite at 134 GPa, with the flax composite having the lowest value of 70 GPa. These findings suggest that biodegradable composites, particularly carbon and flax-based materials, could serve as viable alternatives to traditional materials in e-scooter chassis applications. However, further research is required to validate their performance under real-world conditions.

Abstract: The main aim of the research work is to develop a sustainable vitrimer composite that can be easily recyclable and reusable carbon fibre for secondary applications. Vitrimer materials provide opportunities for recycle thermosets and CFRP composites, however, the retained properties of composite still limit their applications. In this research work, the focus is to investigate material properties of vitamer/carbon fiber composite and the retained properties after recycling of the same. A vitrimer material has been developed using an epoxy (EP) matrix and bio-based curing agent and citric acid (CA), and finally reinforced with carbon fibre. The vitrimer materials were prepared with varying ratios of acid to the epoxy ratio between 0.30 and 0.40 to prepare the best performance vitrimer. Fourier transform infrared (FTIR) spectrometry was conducted in Transmittance mode over a range of wavelengths from 400 to 4000 cm^-1. The mechanical testing carried out at room temperature under tensile loading. Results found that the Vitrimer composite could be effectively dissolved in DMF, enabling the recovery of the carbon fibers. The results of the study indicate that the EP/CA vitrimers exhibit thermomechanical properties that are comparable to those of the epoxy vitrimer cured using a petroleum-based curing agent. The most important results that demonstrate the use of EP/CA vitrimers may be a promising alternative to traditional epoxy composites in various applications.

Abstract: The microstructure of carbon fibers with different properties also varies. Even with considerable mechanical properties, the microstructure characteristics of carbon fibers produced by different manufacturers or processes are different. Although current characterization testing methods can provide a fundamental analysis of the relationship between the microstructure and mechanical properties of carbon fibers, there is still no systematic theory on how to control the evolution of their microstructure during the production process of carbon fibers and develop high-performance and high-quality fibers. There is still a certain gap in the performance of carbon fibers in China compared to foreign countries. Therefore, this article analyzes and summarizes various publicly published models of carbon fiber microstructure in recent years, providing reference for establishing a recognized analysis model that can predict the mechanical properties of carbon fibers in engineering, providing effective direction for improving carbon fiber manufacturing processes, and providing technical support for developing high-performance and high-quality carbon fibers.

Abstract: Composites of natural fiber-reinforced thermoplastic and thermoset polymers have been studied for developing prosthetic socket materials. This study investigated the abaca fiber (AF)/carbon fiber (CF)/epoxy (EP) hybrid composite properties: i.e., tensile, flexural, impact, thermal, and water absorption, by varying AF and CF ratios of 1: 0, 0: 1, 2: 1, 3: 1, and 4: 1 with 80 vol% epoxy resin. The cracks formed in bending test specimens were characterized with an optical microscope, whereas the tensile fracture surface was characterized by scanning electron microscopy (SEM). The results confirmed that the mechanical properties of the CF/EP composite are the highest. The higher the AF/CF ratio, the lower the hybrid composite's mechanical properties and the higher the water absorption. The hybrid composite with a 2:1 AF/CF ratio achieved the highest tensile and flexural strengths of 70 MPa and 103 MPa, respectively, and the lowest water absorption of 7.89%. Based on the experimental results, a simulation of the prosthetic socket was performed using Autodesk Inventor 2019 integrated with ANSYS Workbench 2019 R1, resulting in von Mises stress of 2.14 MPa and deformation of 0.015 mm. Besides, its thermal gravimetric analysis (TGA) resulted in good thermal stability.

Abstract: The National Football League (NFL) is the most successful professional league in the United States. It is also a popular sport around the world. However, for the NFL the strongest problem it has faced is the high rate of concussions, because between seasons and during practices frontal collisions in the head are very recurrent, this concern has led to improve and modify issues in the design of helmets to protect the integrity of the player, Developed by the companies responsible for the manufacture of protective equipment, although in recent decades technological evolution has been an auxiliary tool for the improvement of equipment in this sport discipline there is still a gap to guarantee the total safety of the player. According to the literature, the changes that the helmet structure has undergone are observed and have the perspective, but with regard to the materials that integrate the same materials are still preserved. Therefore, for this research work, the interest arises in developing a numerical analysis that considers new materials, since from 1939 to 2018 the shell material has not been innovated. For this reason, the Speed Flex football helmet that the company Riddell brought to market in 2018 is designed, respecting the helmet structure, where the comparison of the material that is currently used against a composite material, such as carbon fiber, is made, to visualize the results for displacements, Stresses, and total strain during a frontal impact.

Abstract: The manufacturing industry has witnessed substantial interest in the advancement of 4D printing technology in recent years. This technology has enabled the production of complex structures with enhanced functionality and adaptability. Fused Deposition Modeling (FDM) has become a preferred technique for 4D printing due to its ease of use, affordability, and versatile nature. To achieve efficient and effective 4D printing, the process parameters must be optimised to ensure the desired shape recovery behaviour of the printed parts. The main objective of this study is to optimize the process parameters for the production of 4D printed components using FDM technology and Carbon Fiber reinforced Poly Lactic Acid (CF/PLA) Shape Memory Polymer Composites (SMPCs). This study examines the shape recovery properties of the printed components by modifying the process parameters, including Infill Density (ID), Geometrical Thickness (GT), and Bending Angle (BA), through the implementation of Design of Experiments (DOE) L9 Orthogonal Array (OA). Utilizing Analysis of Variance (ANOVA) to determine the significant factors and their optimum levels, the process parameters are statistically analysed. The results indicate that ID and GT are the statistically significant parameters, and the optimum levels for parameters includes 20% ID, 1.5mm GT, and 30⁰ BA led to faster shape recovery. This study demonstrates the effectiveness of the Taguchi approach in the design and optimization of the process parameters for 4D printed parts using FDM.

Abstract: Tendons (cables or rods) are commonly employed as tension members in civil infrastructure, as well as buildings and offshore engineering structures. This study focuses on reliability evaluation of composite rods consisting of polymer matrix (carbon fiber/glass fiber hybrid thermoplastic composite rods (hybrid composite rods) and basalt fiber/polypropylene composite rod (BF/PP composite rod)). Optical and gravimetric methods were used to characterize the morphologies, including constituent volume fractions, of the composite rods. The hybrid composite rods are braided structures with varying diameters and braid angles. The BF/PP composite rod exhibits slight twisting. The volume fractions of the constituent elements (carbon fiber, glass fiber, basalt fiber, matrix, and void) were evaluated. Tensile and flexural tests were conducted under static and fatigue loadings. During the static tensile test, the stress applied to the composite rods was almost linearly proportional to the strain. The fiber-dominant behaviors of the composite rods were observed. During the static flexural test, the stress-strain relationship was initially linear, but as the stress approached its maximum, deformation became non-linear, and finally, the fibers fractured rapidly. During the fatigue tensile and flexural tests, the regression lines of the full-logarithmic curves showed good agreement with the fatigue test data. In addition, data was collected and statistical analyses were performed to assess the effects of environmental factors, such as temperature, on the static properties of the composite rods.

Abstract: A 3d printer has been prototyped for additive manufacturing of carbon fiber (CF) poly-ether-ketone-ketone (PEKK) composites. The machine consisted of a SCARA robot, equipped with an extrusion device. The nozzle was designed to allow the deposition of thin unidirectional (UD) tapes without affecting the fiber continuity. An elastic connection between the robot end-effector and the extruder was used for allowing tape agglomeration during manufacturing. Deposition tests were carried out at the extrusion temperature of 400°C and the rate of 130 mm/min, for a maximum number of 3 layers on a CF-epoxy laminate as substrate. The good agglomeration of the 3d printed parts and their adhesion on the composite substrate are shown by the resulted final thickness, and the ability to machine them by end milling. Results show the feasibility of using this technology for the manufacturing of composite shims in the aeronautic sector.

Abstract: Nowadays, drilling is one of the most widespread operations due to the need to obtain holes for mechanical joints. This operation is particularly relevant in the aeronautical sector due to the high number of operations performed, the high demands and the use of materials that are difficult to machine. The use of materials that enhance aircraft performance, such as carbon fiber composites (CFRP), poses a challenge for axial drilling operations. The characteristics of these materials and typical defects such as delamination are difficult to control due to the axial forces produced during drilling operations. Therefore, more efficient alternatives are required. In this context, helical milling operations have advantages such as lower axial stress, higher flexibility, and higher efficiency in heat and chip evacuation that put it in the spotlight. In this work, research has been carried out in which helical milling operations have been performed on CFRP. The main objectives were the analysis of surface quality, delamination, tool wear and force analysis. For this purpose, a working methodology has been developed combining machining parameters that define the kinematics of the cutting process (cutting speed, axial feed rate, and tangential feed rate). Finally, this information has allowed finding a correlation between quality indicators such as delamination and the forces generated during the cutting process and associated with progressive tool wear. The results show that the force signal could be used for on-line monitoring of the machining process.