Fiber Reinforced Plastic Research Articles

Assessment of life cycle environmental impacts of materials, driving pattern, and climatic conditions on battery electric and hydrogen fuel cell vehicles in a cold region

Battery electric vehicles (BEVs) and hydrogen fuel cell vehicles (HFCVs) can play an important role in addressing climate change by diminishing greenhouse gas (GHG) emissions in the worldwide road transportation sector. There is limited research on the implications of the use of lightweight materials, driving pattern, and climatic impact on the life cycle GHG emissions in a cold region. To address this limitation, we developed a framework to assess eighteen BEV and four HFCV scenarios for a cold region that consider aforementioned parameters through a combination of driving patterns (in rural, city, and highway driving) and climatic conditions (i.e., summer, mild winter, and severe winter) for both conventional and carbon fiber-reinforced plastic (CRFP)-based BEVs. A case study was conducted for Canada, considering its cold regions, using available data for HFCVs. We assessed city driving in summer and highway driving in severe winter conditions for conventional and CFRP-based HFCVs. The results show that the lowest GHG emissions are in cities in summer, with life cycle GHG emissions values of 68.7 g CO2 eq/km for CFRP-based BEVs. The highest life cycle GHG emissions are 364.4 g CO2 eq/km with conventional HFCVs on the highway in severe winter conditions' scenario. The operation phase emerges as the primary contributor to life cycle GHG emissions, closely trailed by the production phase. The analysis shows that the most sensitive parameters for CFRP-based BEVs in the city in summer scenario are vehicle lifetime and for conventional HFCVs in the highway in severe winter scenario, fuel cell efficiency. The analysis also shows the range of life cycle GHG emissions for a cold region, with conventional HFCVs on highways in severe winter conditions exhibiting the highest emissions (331.0 g CO2 eq/km) and CFRP-based HFCVs in the city in summer scenario the lowest (51.0 g CO2 eq/km).

Child Seat Structure Made of Bio-based and Natural Fiber-reinforced Plastics

Child Seat Structure Made of Bio-based and Natural Fiber-reinforced Plastics

Multi-Directional Strain Measurement in Fiber-Reinforced Plastic Based on Birefringence of Embedded Fiber Bragg Grating.

Embedded fiber Bragg gratings are increasingly applied for in-situ strain measurement in fiber-reinforced plastics, integral to high-end aerospace equipment. Existing research primarily focuses on in-plane strain measurement, limited by the fact that fiber Bragg gratings are mainly sensitive to axial strain. However, out-of-plane strain measurement is equally important for comprehending structural deformation. The birefringence of fiber Bragg gratings shows promise for addressing this problem; yet, the strain transfer relationship between composites and optical fibers, along with the decoupling method for multi-directional strains, remains inadequately explored. This study introduces an innovative method for multi-directional strain measurement in fiber-reinforced plastics using the birefringence of a single-fiber Bragg grating. The strain transfer relationship between composites and embedded optical fibers was derived based on Kollar's analytical model, leading to the development of a multi-directional strain decoupling methodology. This method was experimentally validated on carbon fiber/polyetherimide laminates under thermo-mechanical loading. Its reliability was confirmed by comparing experimental results and finite element simulations. These findings significantly broaden the application scenarios of fiber Bragg gratings, advancing the in-situ measurement technology crucial for the next generation of high-end aerospace equipment.

Investigation of the effect of symmetrical hybrid stacking on drilling machinability of unidirectional CFRP, GFRP and hybrid composites: Drilling tests and damage analysis

Fiber-reinforced plastics are undoubtedly superior to metals in many sectors due to their advantageous properties. Especially carbon fiber reinforced plastics (CFRP) and glass fiber reinforced plastics (GFRP) are widely used in industry. Although CFRP offers higher strength, its use is limited due to its high cost. However, with hybridisation, it is possible to produce composites that will provide sufficient strength at lower cost. The mechanical behaviour of hybrid composites may be different compared to glass or carbon composites, as well as the damage behaviour during machining. In this study, the influence of hybrid stacking in drilling hybrid composites was investigated. The results showed the hybrid stacking, especially the position of the carbon plate, has a significant impact on the force generation and damage formation in the drilling. Although stacking the carbon layer at bottom caused an increase in thrust forces, it reduced the damage formation at the hole exit.

Research on mechanical performance of longitudinal joints in segmental tunnel linings strengthened by fiber-reinforced plastic grid with polymer-cement-mortar method

Research on mechanical performance of longitudinal joints in segmental tunnel linings strengthened by fiber-reinforced plastic grid with polymer-cement-mortar method

Performance-tunable thermal barrier coating for carbon fiber-reinforced plastic composites via flame spraying

Thermal barrier coatings (TBCs) are essential for improving the heat resistance of materials operating in high-temperature environments. This paper proposes a new method for manufacturing double-layered TBC with graded porosity for carbon fiber-reinforced plastic (CFRP) composites. The TBC was created by a flame spraying process, consisting of relatively dense and porous layers: (1) a dense layer was produced by spraying yttria-stabilized zirconia (YSZ) particles directly onto neat carbon fabric substrate and (2) a porous layer was prepared by co-spraying YSZ particles with sacrificial polyetheretherketone (PEEK) particles. The porosity of the porous layer was controlled by varying a PEEK injection distance (D) and a PEEK feed rate (R). The correlation between porosity and thermal conductivity of the TBC layer was investigated to assess its thermal barrier performance. The TBC fabricated with the D = 5 cm and the R = 1.0 g/min offered the optimal porosity and conductivity. The 640μm-thick TBC with 34% porosity and 0.27 W/m·K thermal conductivity protected the CFRP substrate remarkably under the subjected torch at 500°C, as the TBC layer reduced the surface temperature of CFRP to 230°C. Thermomechanical analysis, following thermal shock tests, revealed that the double-layered TBC/CFRP composite retained 87% and 75% of its pristine flexural strength and modulus, respectively, while the neat CFRP composite was completely burnt out. This study explored the application of flame spray technology to develop highly effective double-layered TBCs with tunable porosity to maximize their thermal barrier performances. All results from the current study provide new insights into the design and development of TBC and CFRP composites, which will benefit a wide range of lightweight high-temperature applications.

Upcycling Post-Consumer Paint Pail Plastic Waste.

The need for ending plastic waste and creating a circular economy has prompted significant interest in developing a new family of composite materials through recycling and recovery of waste resources (including bio-sourced materials). In this work, a family of natural fiber-reinforced plastic composites has been developed from paint pail waste recycled polypropylene (rPP) and waste wool fibers of different diameter and aspect ratio. Composites were fabricated by melt processing using polypropylene-graft-maleic anhydride as a compatibilizer. The internal morphology, interfacial and thermal characteristics, viscoelastic behavior, water sorption/wettability, and mechanical properties of composites were studied using electron microscopy, high-resolution synchrotron Fourier transform infrared microspectroscopy, thermal analysis, rheology, immersion test, contact angle measurement, tensile test and flexural test. The composite matrix exhibited an internal morphology of coalescent micro-droplets due to the presence of polyethylene and dry paint in the rPP phase. In general, the rheological and mechanical properties of the composites comprising higher-aspect-ratio (lower diameter) fibers exhibited relatively superior performance. About an 18% increase in tensile strength and a 39% increase in flexural strength were measured for composites with an optimal fiber loading of 10 wt.%. Interfacial debonding and fiber pull-out were observed as the main failure mechanism of the composites. The developed composites have potential for applications in automotive, decking, and building industries.

Molecular dynamics simulation of deposition of high waxy crude oil on different pipeline walls

ABSTRACT Wax deposition occurs in the process of waxy crude oil pipeline transportation, which seriously affects the normal operation of crude oil pipeline. At present, non-metallic pipes have been proved to be effective in delaying the occurrence of wax deposition. Therefore, based on the pipeline walls of 20 G steel, glass fiber reinforced plastic (FRP), and polyethylene (PE), the microscopic mechanism of wax deposition during the pipeline transportation of waxy crude oil was studied by molecular dynamics simulation. The simulation results show that the waxy crude oil clusters undergo diffusion, deposition, reverse diffusion processes, and finally a wax deposition layer is formed on the pipeline surface. On the pipe walls of different materials, the surface free energy affects the interface energy of the solid-liquid contact surface between the waxy crude oil and the pipe wall, which is the main factor for the low surface free energy pipe to have the anti-wax effect. At the same time, according to the analysis of the contact angle on different materials in the simulation results, the difference in pipeline materials can only delay the formation speed of the wax deposition layer and cannot completely prevent the occurrence of wax deposition..

Spot-checking machine learning algorithms for tool wear monitoring in automatic drilling operations in CFRP/Ti6Al4V/Al stacks in the aircraft industry

In aircraft manufacturing, where diverse materials, including Carbon Fiber-Reinforced Plastics (CFRP), aluminum, and titanium alloys, are employed, the assembly process heavily relies on creating thousands of holes. These holes accommodate bolts and rivets, facilitating the secure interlocking of structural components within the aircraft fuselage. The proliferation of sensor systems in this domain has led to a substantial increase in data generation during the hole-making process, offering a compelling opportunity to optimize the production system. In this context, this article is dedicated to harnessing the data collected from the production system of a commercial aircraft to refine the assembly process, with a specific focus on reducing consumable costs. The primary approach involves developing a real-time Tool Wear Monitoring System by comparing the performance of Linear Regression, Lasso Regression, Ridge Regression, k-Nearest Neighbors, Support Vector Regression, Decision Tree, Random Forest, and Extreme Gradient Boosting Machine Learning models. Using a scale of the general drill condition as an outcome, the Gradient Boosting Regressor has shown outstanding results. Notably, the residuals consistently exhibited zero-centered errors in training and test sets. However, it suggests that further enhancements are needed to surpass human-level performance in predicting tool conditions because of the quality and quantity of available data.

The ways and mechanisms of using CFRP materials to strengthen the flexural performance of reinforced concrete beams

Due to the increasing demand for structural strengthening and retrofitting solutions, Fiber-reinforced plastic (FRP) materials has emerged as a promising technology to improve the performance of existing structures. FRP material is a composite material composed of fiber-reinforced plastics, known for its excellent strength and resistance to corrosion. The primary components of this material consists of various fibers, such as glass fiber, carbon fiber, or aramid fiber, along with a resin matrix, such as epoxy resin, polyester resin. FRP materials are commonly employed in construction engineering to enhance the flexural strength of concrete structures. This paper, through methods of literature review and building physical models, investigates the effectiveness of Carbon Fiber Reinforced Polymer (CFRP) materials in enhancing the bending strength of reinforced concrete beams. This study aims to examine the impact of carbon fiber reinforced polymer (CFRP) sheets on the flexural strength of reinforced concrete beams, which aims to establish calculation formulas based on the specific impacts observed. The findings of this study demonstrate the capacity of FRP materials, specifically CFRP materials, to improve the bending strength of reinforced concrete beams. The usage of FRP materials for structural reinforcement offers a durable, corrosion-resistant, and lightweight solution that can prolong the lifespan and improve the structural efficacy of existing infrastructure.

Prediction of the Interface Behavior of a Steel/CFRP Hybrid Part Manufactured by Stamping.

Carbon fiber-reinforced plastic (CFRP) is a lightweight material. The automotive industry has focused on producing a steel/CFRP hybrid part to reduce overall weight. After manufacturing, delamination can occur at the interface between the CFRP and steel owing to the hybrid part constituting dissimilar materials. However, most studies have focused only on designing the manufacturing processes for the hybrid part or evaluating the adhesive used at the interface. Therefore, it is necessary to predict the behavior of the interface after demolding the hybrid part. This study aimed to predict the interface behavior of a steel/CFRP hybrid part by considering its forming and cohesive properties. First, double cantilever beam (DCB) and end-notched flexure (ENF) tests were performed to obtain cohesive parameters, such as energy release rate of modes I and II (GI, GII). The experimentally obtained properties were applied to the bonding area of the hybrid part. Subsequently, a forming simulation was performed to obtain the stress of the steel blank in the hybrid part. The stress distribution after forming was utilized as the initial condition for spring-back simulation. Finally, the interface behavior of the hybrid part was predicted by a spring-back simulation. The simulation was conducted using the residual stress of steel outer and the cohesive properties on the interface, without the application of any external forces. The cases of spring-back simulation were divided as delamination occurrence and attached state. The simulation results for prediction of delamination occurrence and bonding showed good agreement in both cases with experimental ones. The proposed method would contribute to expanding the manufacturing of the hybrid part by stamping and reducing the manufacturing cost by prediction of delamination occurrence.

Straw Tar Epoxy Resin for Carbon Fiber-Reinforced Plastic: A Review.

The massive consumption of fossil fuels has led to the serious accumulation of carbon dioxide gas in the atmosphere and global warming. Bioconversion technologies that utilize biomass resources to produce chemical products are becoming widely accepted and highly recognized. The world is heavily dependent on petroleum-based products, which may raise serious concerns about future environmental security. Most commercially available epoxy resins (EPs) are synthesized by the condensation of bisphenol A (BPA), which not only affects the human endocrine system and metabolism, but is also costly to produce and environmentally polluting. In some cases, straw tar-based epoxy resins have been recognized as potential alternatives to bisphenol A-based epoxy resins, and are receiving increasing attention due to their important role in overcoming the above problems. Using straw tar and lignin as the main raw materials, phenol derivatives were extracted from the middle tar instead of bisphenol A. Bio-based epoxy resins were prepared by replacing epichlorohydrin with epoxylated lignin to press carbon fiber sheets, which is a kind of bio-based fine chemical product. This paper reviews the research progress of bio-based materials such as lignin modification, straw pyrolysis, lignin epoxidation, phenol derivative extraction, and synthesis of epoxy resin. It improves the performance of carbon fiber-reinforced plastic (CFRP) while taking into account the ecological and environmental protection, so that the epoxy resin is developed in the direction of non-toxic, harmless and high-performance characteristics, and it also provides a new idea for the development of bio-based carbon fibers.

Fiberglass Construction Testing Simulation On Boat Hulls

As a maritime country, Indonesia relies heavily on ships as an economical means of transportation and conveyance. Boats, which were used for many years, were originally made of wood. However, because wood has properties that are easily weathered due to weather and chemical factors and requires adequate maintenance, fiberglass material in the form of FRP (Fiber Reinforced Plastics) laminates appeared as a substitute for wood. This material has many advantages over wood, so ships made from FRP began to gain a place in the shipping world, especially among ship manufacturers. However, In 2009, a survey carried out at multiple shipyards revealed that the construction design and lamination process of fiberglass ship hulls generally did not have clear standards, resulting in a significant risk of accidents. To minimize this risk, a simulation of fiberglass construction testing was held with samples taken from 6 shipyards where each sample had a different configuration and material, and the results of Carbon Fiber provided optimal results.

Interaction of multiple micro-defects on the strength and failure mechanism of UD composites by computational micromechanics

The mechanical properties of unidirectional fiber-reinforced plastic (UD-FRP) are affected by a variety of micro-defects, such as random fiber arrangement, fiber misalignment and micro-voids. This study aims to investigate how these multiple micro-defects interact with each other and how they affect the strength and failure mechanism of UD-FRP by means of computational micromechanics. The composite behavior was simulated by the finite element analysis of a representative volume element of the composite microstructure in which the random distribution of fibers, the micro-voids, and the fiber misalignment are explicitly included. Both matrix and interface failure were considered for the loadings of transverse tension/compression, longitudinal compression, transverse/longitudinal shear, and their combination. It was found that these three micro-defects significantly weakened the compressive strength of UD-FRP along the longitudinal direction. Especially, the fiber misalignment magnified the effect of fiber arrangement, while the micro-voids reduce the effect. Besides, the fiber arrangement and micro-voids significantly weakened the tensile and compressive strength of UD-FRP along the transverse direction, but their interaction effect was not obvious. Moreover, transverse and longitudinal shear strength are significantly affected by micro-voids, but only longitudinal shear is affected by geometric fiber arrangement, and this effect is also weakened by micro-voids. Finally, the damage envelope under the combined longitudinal compression and transverse loads was obtained and compared with the Tsai-Wu failure criterion. The results showed that the Tsai-Wu criteria can provide an effective estimation for the failure locus under this biaxial loading condition.

Deep transfer learning for efficient and accurate prediction of composite pressure vessel behaviors

Composite pressure vessels are manufactured by winding carbon fiber-reinforced plastic, while its performance is determined by fabrication conditions. To properly design composite pressure vessels, it is essential to analyze their behavior according to the design parameters. However, analytical or numerical methods have limitations in terms of accuracy or cost-effectiveness. In this study, a method is proposed to accurately and efficiently predict the behavior of composite pressure vessels through deep transfer learning. A prediction model is built by pre-training on a sufficient amount of analytical data, and then fine-tuning on a limited amount of numerical data. The performance of the deep transfer learning-based prediction model was evaluated through various error assessments. Its computational cost was also compared with that of finite element analysis. Furthermore, the deep transfer learning-based prediction model was used to analyze the impact of design parameters on the behavior of composite pressure vessels and for design optimization.

In situ growth and crystallization behavior of PP crystals induced by CF under supercritical N2

High-performance carbon fiber reinforced polypropylene (PP/CF) composite foams were successfully prepared using supercritical N2 as a physical blowing agent, significantly reducing raw material usage. However, the incorporation of supercritical N2 complicates the crystallization behavior of PP/CF, subsequently affects their property. Herein, this study proposes to prepare PP/CF films by solution method and observe in situ growth and crystallization behavior of PP crystals induced by CF under supercritical N2 for the first time. Numerous nucleation sites are formed in CF under supercritical N2, facilitating transcrystalline formation at the interface and confirming CF's potent heterogeneous nucleation capability. The surface tension effect of CF was visualized for the first time, noting the transformation of spherulites into dendritic structures. This transformation, becoming more pronounced with successive isothermal crystallizations, is attributed to changes in the rheological behavior of the PP melt. Furthermore, the research elucidates the mechanism behind CF-induced transcrystalline formation and the periodic growth of the crystal front under supercritical N2. A 20%CF addition reduced grain size by 41.2 % and increased grain density by 2.7 times at 130 °C. However, a higher CF content raises the interfacial free energy required for nucleation, leading to a slower grain growth rate. This work not only addresses the gap in understanding fiber-induced crystallization under supercritical gases but also lays a theoretical foundation for the crystallization behavior of other fibers under similar conditions. It provides critical insights for developing fiber-reinforced composite microcellular plastics with superior properties.

Surface physics and chemistry of carbon fibers enhance dissimilar sheet joining of carbon fiber-reinforced plastic by copper electrodeposition

Carbon fiber-reinforced plastic (CFRP) sheets were dissimilarly edge-joined with anodized A6061 Al alloy sheets by copper electrodeposition. A high bonding strength of 137 MPa was attained following a series of pretreatments including etching in KMnO4 + NaOH hot aqueous solution, anodization at 2 V vs. SUS316 cathode in 1 mol L˗1 H2SO4, and sulfonation in hot concentrated H2SO4. The anodization physically cleaned the carbon fiber (CF) surface in CFRP. The chemical surface properties of the CFs were modified by the anodization, introducing crystallographic defects and CO groups. This physical and chemical modification of CFs in CFRP resulted in good adhesion of the electrodeposited copper.

Research on Acid Aging and Damage Pattern Recognition of Glass Fiber-Reinforced Plastic Oil and Gas Gathering Pipelines Based on Acoustic Emission.

Pipelines extend thousands of kilometers to transport and distribute oil and gas. Given the challenges often faced with corrosion, fatigue, and other issues in steel pipes, the demand for glass fiber-reinforced plastic (GFRP) pipes is increasing in oil and gas gathering and transmission systems. However, the medium that is transported through these pipelines contains multiple acid gases such as CO2 and H2S, as well as ions including Cl-, Ca2+, Mg2+, SO42-, CO32-, and HCO3-. These substances can cause a series of problems, such as aging, debonding, delamination, and fracture. In this study, a series of aging damage experiments were conducted on V-shaped defect GFRP pipes with depths of 2 mm and 5 mm. The aging and failure of GFRP were studied under the combined effects of external force and acidic solution using acoustic emission (AE) techniques. It was found that the acidic aging solution promoted matrix damage, fiber/matrix desorption, and delamination damage in GFRP pipes over a short period. However, the overall aging effect was relatively weak. Based on the experimental data, the SSA-LSSVM algorithm was proposed and applied to the damage pattern recognition of GFRP. An average recognition rate of up to 90% was achieved, indicating that this method is highly suitable for analyzing AE signals related to GFRP damage.

Optimization method for low-velocity impact identification in nanocomposite using genetic algorithm

Abstract Fiber-reinforced plastic (FRP) is prone to invisible damage caused by low-velocity impact (LVI) during service. The structural health monitoring system is of great significance for damage monitoring and maintenance of composite materials. In this study, four fiber Bragg grating sensors were employed to collect the time domain strain signals of composite materials subjected to LVIs. Furthermore, a numerical simulation model was established to rapidly obtain impact signal dataset. The signal arrival time, peak time, and peak amplitude were selected as signal features, and the backpropagation neural network was successfully applied to determine the location and energy of LVIs. To address the issue of peak feature extraction in the strain signal processing, a genetic algorithm-based sliding window peak detection optimization method was proposed, which significantly improved the final prediction accuracy. The experimental results indicated that within a position range of 300 mm × 300 mm, the average positioning error can reach 5.1 mm; and in an energy range of 0.5–1 J, the average energy prediction error can reach 0.030 J. The proposed method achieved accurate identification of the LVI location and energy for FRP.

Characterisation of basalt/glass/kevlar-29 hybrid fibre-reinforced plastic composite material through Nd: YAG laser drilling and optimisation using stochastic methods

Characterisation of basalt/glass/kevlar-29 hybrid fibre-reinforced plastic composite material through Nd: YAG laser drilling and optimisation using stochastic methods