Pub Date : 2024-06-01DOI: 10.1177/00219983241261065
Tomás Barros Vasconcelos, José Leandro Correia Alves, Evans Paiva da Costa Ferreira, Raimundo Carlos Silverio Freire Júnior, José Daniel Diniz Melo
Double-double (DD) configuration has been proposed as a new concept in which a double set of double helix [±ϕ/± ψ]n angles are stacked up to form a composite laminate. This concept promises significant advantages over conventional layups for composite design optimization and manufacturing. This experimental study evaluated the performance of two elastically in-plane equivalent glass/epoxy laminates suited for wind turbine blade applications: a quadriaxial (Quad) [±45/(0/90)3]s and a double-double (DD) [±15/±75]4T. Mechanical tests were performed under cyclic uniaxial tensile-tensile load using unnotched and open hole specimens. Delamination initiating from the free edges resulted in premature failure of the unnotched DD specimens. For open hole specimens, fatigue tests results obtained from both stacking sequences showed similar performance. Ultimately, the study presented constitutes a valuable contribution to the understanding of fatigue behavior of double-double glass/epoxy laminates subjected to tensile cyclic loading.
{"title":"Static and fatigue behavior of double-double glass/epoxy laminates","authors":"Tomás Barros Vasconcelos, José Leandro Correia Alves, Evans Paiva da Costa Ferreira, Raimundo Carlos Silverio Freire Júnior, José Daniel Diniz Melo","doi":"10.1177/00219983241261065","DOIUrl":"https://doi.org/10.1177/00219983241261065","url":null,"abstract":"Double-double (DD) configuration has been proposed as a new concept in which a double set of double helix [±ϕ/± ψ]<jats:sub>n</jats:sub> angles are stacked up to form a composite laminate. This concept promises significant advantages over conventional layups for composite design optimization and manufacturing. This experimental study evaluated the performance of two elastically in-plane equivalent glass/epoxy laminates suited for wind turbine blade applications: a quadriaxial (Quad) [±45/(0/90)<jats:sub>3</jats:sub>]<jats:sub>s</jats:sub> and a double-double (DD) [±15/±75]<jats:sub>4T</jats:sub>. Mechanical tests were performed under cyclic uniaxial tensile-tensile load using unnotched and open hole specimens. Delamination initiating from the free edges resulted in premature failure of the unnotched DD specimens. For open hole specimens, fatigue tests results obtained from both stacking sequences showed similar performance. Ultimately, the study presented constitutes a valuable contribution to the understanding of fatigue behavior of double-double glass/epoxy laminates subjected to tensile cyclic loading.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"47 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141196637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01DOI: 10.1177/00219983241259130
Muhammad Ali Bablu, Nicholas E Nowak, James M Manimala
The possibility of enhancing the ballistic performance of aramid fabrics such as Kevlar through the impregnation of nanoparticles is well established. In this study, the influence of the nanoparticle’s specifications such as size, shape, and material on the underlying mechanisms is investigated. A colloid-based treatment process is used to impregnate dry nanoparticles into Kevlar fabric. Using a customized gas gun rig, neat and treated samples are tested to determine the kinetic energy absorbed. Silica, alumina, and zinc oxide nanoparticles ranging from 10 to 125 nm, with spherical or cylindrical shape are considered. Silica treated samples perform significantly better (83% increase in energy absorbed vs neat fabric) than alumina or zinc oxide treated samples, likely due to greater agglomeration between yarn interfaces leading to enhanced frictional mechanisms. The exit-face damaged zone area acts as a surrogate for energy absorbed as it correlates well across all samples. Compared to samples with three layers treated individually, samples with three layers treated together display a 21% enhancement in the energy absorbed. Specific energy absorbed for three layers treated together with 80-nm silica is nearly 3 times higher than that for the neat fabric. Samples with three layers treated together with 80-nm silica provide the same performance as the neat fabric for a projectile that is nearly 70 m/s faster. Hybrid structural materials such as nanoparticle-fabric composites offer a promising route to enhance ballistic performance without weight penalty, while being amenable to multifunctional applications.
{"title":"Role of particle material and geometry in the ballistic performance of nanoparticle-impregnated Kevlar fabric","authors":"Muhammad Ali Bablu, Nicholas E Nowak, James M Manimala","doi":"10.1177/00219983241259130","DOIUrl":"https://doi.org/10.1177/00219983241259130","url":null,"abstract":"The possibility of enhancing the ballistic performance of aramid fabrics such as Kevlar through the impregnation of nanoparticles is well established. In this study, the influence of the nanoparticle’s specifications such as size, shape, and material on the underlying mechanisms is investigated. A colloid-based treatment process is used to impregnate dry nanoparticles into Kevlar fabric. Using a customized gas gun rig, neat and treated samples are tested to determine the kinetic energy absorbed. Silica, alumina, and zinc oxide nanoparticles ranging from 10 to 125 nm, with spherical or cylindrical shape are considered. Silica treated samples perform significantly better (83% increase in energy absorbed vs neat fabric) than alumina or zinc oxide treated samples, likely due to greater agglomeration between yarn interfaces leading to enhanced frictional mechanisms. The exit-face damaged zone area acts as a surrogate for energy absorbed as it correlates well across all samples. Compared to samples with three layers treated individually, samples with three layers treated together display a 21% enhancement in the energy absorbed. Specific energy absorbed for three layers treated together with 80-nm silica is nearly 3 times higher than that for the neat fabric. Samples with three layers treated together with 80-nm silica provide the same performance as the neat fabric for a projectile that is nearly 70 m/s faster. Hybrid structural materials such as nanoparticle-fabric composites offer a promising route to enhance ballistic performance without weight penalty, while being amenable to multifunctional applications.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"121 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141196580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Automated fiber placement (AFP) in situ consolidation (ISC) of thermoplastic composite possess the potential to reduce manufacturing costs and improve manufacturing efficiency. The properties of composite manufactured by the ISC are affected by several mechanisms including polymer degradation, crystallization, intimate contact, polymer healing and void dynamics. All these mechanisms are directly affected by the temperature history. Consequently, the control and accurate measurement of temperature history during ISC are particularly important for improving the properties of composite. In this study, a simplified three-dimensional transient heat transfer model was established. The effect of tool temperature and placement speed on the temperature history and peak temperature were predicted. Simultaneously, an online temperature monitoring system was built and the optical Fiber Bragg Grating sensors (FBGS) was used to measure the temperature history. The results indicated that the predicted results of the model were consistent with the measured results, the error was below 8%. In addition, the temperature history of layers was significantly affected by the tool temperature and placement speed. The temperature of the layers decreased to near the tool temperature after cooling, and a higher tool temperature increasing its peak temperature because of the reduce of the cooling rate. On the contrary, an increase in placement speed will reduce the peak temperature of the layers.
{"title":"Simulation and on-line monitoring using optical fiber Bragg grating sensors of temperature history during laser-assisted automated fiber placement","authors":"Dacheng Zhao, Weiping Liu, Jiping Chen, Songhao Zhu, Yang Yang, Guangquan Yue","doi":"10.1177/00219983241259849","DOIUrl":"https://doi.org/10.1177/00219983241259849","url":null,"abstract":"Automated fiber placement (AFP) in situ consolidation (ISC) of thermoplastic composite possess the potential to reduce manufacturing costs and improve manufacturing efficiency. The properties of composite manufactured by the ISC are affected by several mechanisms including polymer degradation, crystallization, intimate contact, polymer healing and void dynamics. All these mechanisms are directly affected by the temperature history. Consequently, the control and accurate measurement of temperature history during ISC are particularly important for improving the properties of composite. In this study, a simplified three-dimensional transient heat transfer model was established. The effect of tool temperature and placement speed on the temperature history and peak temperature were predicted. Simultaneously, an online temperature monitoring system was built and the optical Fiber Bragg Grating sensors (FBGS) was used to measure the temperature history. The results indicated that the predicted results of the model were consistent with the measured results, the error was below 8%. In addition, the temperature history of layers was significantly affected by the tool temperature and placement speed. The temperature of the layers decreased to near the tool temperature after cooling, and a higher tool temperature increasing its peak temperature because of the reduce of the cooling rate. On the contrary, an increase in placement speed will reduce the peak temperature of the layers.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"42 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141196582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-31DOI: 10.1177/00219983241256334
Mohammad Javad Ramezani
This study examined the impact behavior of carbon/epoxy and glass/epoxy composite laminates with 2, 4, and 6 mm thicknesses under low-velocity tests. The investigation involved subjecting the composite laminates under small-impact loads using spherical, cylindrical, and conical steel projectiles, each weighing 3 g. The impacts conducted at 29.5, 36.5, and 51 m/s velocities. This investigation modeled using finite element (FE) methods and analytical approaches. In the analytical method, the mass and spring model used for the impact of small projectiles. The research findings revealed that, in 2 mm thick carbon/epoxy composite laminates, the maximum deflection at the mid-point induced by a spherical projectile was 1.37 mm. This value exhibited a 48.91% and 19.13% increase compared to impacts with cylindrical and conical projectiles, respectively. Additionally, a comprehensive examination of delamination across all samples indicated the maximum delamination occurrence in glass/epoxy samples, showcasing lower impact resistance than carbon/epoxy laminates. Notably, with an increase in thickness, the delamination phenomenon in the samples exhibited a decreasing trend. In addition, the maximum value of delamination in the composite laminates were with spherical, conical, and cylindrical projectiles respectively, and also, there was an excellent convergence between FE and analytical results.
{"title":"The investigation of deflection behavior in carbon/epoxy and glass/epoxy composite laminates under low-velocity impact with small projectiles","authors":"Mohammad Javad Ramezani","doi":"10.1177/00219983241256334","DOIUrl":"https://doi.org/10.1177/00219983241256334","url":null,"abstract":"This study examined the impact behavior of carbon/epoxy and glass/epoxy composite laminates with 2, 4, and 6 mm thicknesses under low-velocity tests. The investigation involved subjecting the composite laminates under small-impact loads using spherical, cylindrical, and conical steel projectiles, each weighing 3 g. The impacts conducted at 29.5, 36.5, and 51 m/s velocities. This investigation modeled using finite element (FE) methods and analytical approaches. In the analytical method, the mass and spring model used for the impact of small projectiles. The research findings revealed that, in 2 mm thick carbon/epoxy composite laminates, the maximum deflection at the mid-point induced by a spherical projectile was 1.37 mm. This value exhibited a 48.91% and 19.13% increase compared to impacts with cylindrical and conical projectiles, respectively. Additionally, a comprehensive examination of delamination across all samples indicated the maximum delamination occurrence in glass/epoxy samples, showcasing lower impact resistance than carbon/epoxy laminates. Notably, with an increase in thickness, the delamination phenomenon in the samples exhibited a decreasing trend. In addition, the maximum value of delamination in the composite laminates were with spherical, conical, and cylindrical projectiles respectively, and also, there was an excellent convergence between FE and analytical results.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"51 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141196564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The use of hollow glass particle-filled fiber-reinforced composites for aircraft applications requires proper understanding of their behavior under in-service temperature conditions in order to exploit their usage in the exterior parts of aircraft and other space vehicles. In this study, the glass fiber reinforced composites containing 0–30 vol% of glass microspheres were subjected to testing for monotonic tensile and flexural loading from room temperature to the test temperature (40°C – 120°C). The evolution of microscopic damage under different temperatures was elucidated by digital image correlation (DIC) strain fields. The strain fields revealed a transition from homogeneous to non-homogeneous pattern as the temperature increases due to softening of the matrix. As the glass microsphere contents in the matrix increased, the tensile and flexural properties of the composites decreased, and their reduction was highest for the specimen containing a 30 vol% microsphere by volume. The tensile properties are slightly decreased by increasing the temperature. The tensile specimens tested at room temperature exhibited limited delamination and fiber pullout, while extensive delamination and fiber splitting occurred in the specimens tested at 120°C. The flexural results of the glass fiber reinforced composite specimens exposed at 120°C demonstrated a considerable decrease in flexural strength compared with room temperature for 0 vol%, 10 vol%, 20 vol% and 30 vol% glass microsphere volume fraction. Finally, the Weibull parametric investigation was performed to model the degradation of modulus for various GMS contents with temperature variations.
{"title":"Mechanical behavior of glass fiber-reinforced hollow glass particles filled epoxy composites under thermal loading","authors":"Anandakumar Paramasivam, Krishnan Kanny, Mohan Turup Pandurangan, Velmurugan Ramachandran","doi":"10.1177/00219983241259113","DOIUrl":"https://doi.org/10.1177/00219983241259113","url":null,"abstract":"The use of hollow glass particle-filled fiber-reinforced composites for aircraft applications requires proper understanding of their behavior under in-service temperature conditions in order to exploit their usage in the exterior parts of aircraft and other space vehicles. In this study, the glass fiber reinforced composites containing 0–30 vol% of glass microspheres were subjected to testing for monotonic tensile and flexural loading from room temperature to the test temperature (40°C – 120°C). The evolution of microscopic damage under different temperatures was elucidated by digital image correlation (DIC) strain fields. The strain fields revealed a transition from homogeneous to non-homogeneous pattern as the temperature increases due to softening of the matrix. As the glass microsphere contents in the matrix increased, the tensile and flexural properties of the composites decreased, and their reduction was highest for the specimen containing a 30 vol% microsphere by volume. The tensile properties are slightly decreased by increasing the temperature. The tensile specimens tested at room temperature exhibited limited delamination and fiber pullout, while extensive delamination and fiber splitting occurred in the specimens tested at 120°C. The flexural results of the glass fiber reinforced composite specimens exposed at 120°C demonstrated a considerable decrease in flexural strength compared with room temperature for 0 vol%, 10 vol%, 20 vol% and 30 vol% glass microsphere volume fraction. Finally, the Weibull parametric investigation was performed to model the degradation of modulus for various GMS contents with temperature variations.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"51 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141196639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-28DOI: 10.1177/00219983241254889
Lasse Malaske, Lucian-Attila Blaga, Luciano Bermann, Bilal Ahmad, Xiang Zhang, Benjamin Klusemann
During the last decades, environmental concerns and limited resources have set focus of research on lightweight, mechanically high-performing structures for the transportation industry, in order to reduce fuel consumptions and CO2 emissions. Friction Stir Joining (FSJ), as a variant of the Friction Stir Welding (FSW), is an innovative friction-based joining technique for metal-composite hybrid structures. Joining in the plasticized state below the melting temperature of the metal leads to a comparatively small heat-affected zone, so that only minor metallurgical changes occur. Additionally, only a short processing time and no additional weight in form of fasteners is needed. The main objective of this study is to evaluate the feasibility of metal-composite structures via FSJ, intending to enable a macro-mechanical interlocking bonding mechanism. Main focus was given to the integration of an aluminium nub inserted in a carbon fiber-reinforced polyphenylene sulfide (CF-PPS) sheet, to ensure sufficient plasticization of the aluminium part and no degradation in the polymer part. Residual stress arising from the friction stir joining process was also characterised using the Contour method. In this study, aluminium alloy 6082-T6 and CF-PPS composite sheets were used to produce long lap joints. Results have shown that the joints were created at almost constant peak temperature slightly above the melting temperature of the PPS but no physical-chemical changes were detected in the PPS. In addition, the influence of a PPS film as interlayer between the sheets was investigated in order to explore a method for preventing galvanic corrosion. Preliminary results indicate that it is not possible to integrate a metal nub to the CF-PPS without interrupting the PPS film. However, it is possible to create a nub within the PPS film.
{"title":"Feasibility study of friction stir joining of aluminium with carbon fibre reinforced thermoplastic composite","authors":"Lasse Malaske, Lucian-Attila Blaga, Luciano Bermann, Bilal Ahmad, Xiang Zhang, Benjamin Klusemann","doi":"10.1177/00219983241254889","DOIUrl":"https://doi.org/10.1177/00219983241254889","url":null,"abstract":"During the last decades, environmental concerns and limited resources have set focus of research on lightweight, mechanically high-performing structures for the transportation industry, in order to reduce fuel consumptions and CO<jats:sub>2</jats:sub> emissions. Friction Stir Joining (FSJ), as a variant of the Friction Stir Welding (FSW), is an innovative friction-based joining technique for metal-composite hybrid structures. Joining in the plasticized state below the melting temperature of the metal leads to a comparatively small heat-affected zone, so that only minor metallurgical changes occur. Additionally, only a short processing time and no additional weight in form of fasteners is needed. The main objective of this study is to evaluate the feasibility of metal-composite structures via FSJ, intending to enable a macro-mechanical interlocking bonding mechanism. Main focus was given to the integration of an aluminium nub inserted in a carbon fiber-reinforced polyphenylene sulfide (CF-PPS) sheet, to ensure sufficient plasticization of the aluminium part and no degradation in the polymer part. Residual stress arising from the friction stir joining process was also characterised using the Contour method. In this study, aluminium alloy 6082-T6 and CF-PPS composite sheets were used to produce long lap joints. Results have shown that the joints were created at almost constant peak temperature slightly above the melting temperature of the PPS but no physical-chemical changes were detected in the PPS. In addition, the influence of a PPS film as interlayer between the sheets was investigated in order to explore a method for preventing galvanic corrosion. Preliminary results indicate that it is not possible to integrate a metal nub to the CF-PPS without interrupting the PPS film. However, it is possible to create a nub within the PPS film.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"70 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141171081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-27DOI: 10.1177/00219983241257665
Muhammet Mevlüt Karaca, Safa Polat, İsmail Esen
Aluminium alloys are preferred in various fields, especially in the aviation and automotive sectors, due to their lightweight and durable nature. However, their usage is limited due to weak tribological properties such as low hardness and high adhesion tendency against steel. In order to overcome this deficiency, this study aimed to develop AA7075 matrix composites reinforced with BN and MXene. The productions were conducted by powder metallurgy method with these reinforcements in different ratios, both together and separately. The produced composites were characterized primarily by XRD and SEM analyses, followed by measurement of density and porosity values. Wear tests were conducted using the reciprocating ball-on-flat method, at a frequency of 3 Hz, a sliding distance of 100 m, and a stroke distance of 5 mm, with Inox steel ball. The highest improvement in wear rate was realized under 5 N load at 5 wt.% reinforcement ratios of 48% and 42% for BN and MXene, respectively. When 2 wt% BN and MXene reinforcements were applied together, the improvement rate remained around 34%. It can be said that BN and MXene show promising results by providing significant improvements compared to their counterparts in the literature, with MXene especially warranting further investigation.
{"title":"Reciprocating dry sliding wear behaviour of BN@MXene@AA7075 composites","authors":"Muhammet Mevlüt Karaca, Safa Polat, İsmail Esen","doi":"10.1177/00219983241257665","DOIUrl":"https://doi.org/10.1177/00219983241257665","url":null,"abstract":"Aluminium alloys are preferred in various fields, especially in the aviation and automotive sectors, due to their lightweight and durable nature. However, their usage is limited due to weak tribological properties such as low hardness and high adhesion tendency against steel. In order to overcome this deficiency, this study aimed to develop AA7075 matrix composites reinforced with BN and MXene. The productions were conducted by powder metallurgy method with these reinforcements in different ratios, both together and separately. The produced composites were characterized primarily by XRD and SEM analyses, followed by measurement of density and porosity values. Wear tests were conducted using the reciprocating ball-on-flat method, at a frequency of 3 Hz, a sliding distance of 100 m, and a stroke distance of 5 mm, with Inox steel ball. The highest improvement in wear rate was realized under 5 N load at 5 wt.% reinforcement ratios of 48% and 42% for BN and MXene, respectively. When 2 wt% BN and MXene reinforcements were applied together, the improvement rate remained around 34%. It can be said that BN and MXene show promising results by providing significant improvements compared to their counterparts in the literature, with MXene especially warranting further investigation.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"97 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141171072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hybridizing the natural fibers with stronger synthetic fibers could significantly improve the properties of the natural fiber-reinforced composites. The improved mechanical capabilities of fiber reinforced polymers result from the fiber’s capacity for withstanding a more substantial portion of the mechanical load compared to the matrix it replaces. In order to guarantee the efficient transfer of the mechanical load from the matrix to the reinforcement, it is necessary to incorporate a fibrous filler. Transference takes place when the length of the fiber is longer than a specific critical length. Fibers which are shorter than the critical length will pull out from the matrix when tested to a tensile load. In some cases, complete transfer of the load is not performed. The goal of this study is to learn more about flax (FF), glass (GF), and mixtures of flax and glass (FF + GF) short fiber-reinforced PLA-PBS composites. This is performed to find out how the flax/glass combination affects the mechanical properties of PLA-PBS-reinforced short fiber composites. In order to extend their use for industrial applications, these composites were manufactured via extrusion and, afterward, injection molding. Fiber aspect ratios were followed after compounding and injection processing. The analysis of fiber lengths reveals a noteworthy observation: the proportion of fibers exceeding their critical length of 531 µm and 772 µm for FF and GF, respectively, is more significant when flax fibers (FF) and glass fibers (GF) are combined compared to when they reinforce the composite individually. Specifically, the composite containing both FF and GF exhibits a higher percentage of fibers surpassing their critical length, compared to their individual reinforcement in the composite. The results reveal that 27% of individually extracted single FF exceed their critical length, whereas a higher proportion, at 34%, is observed when FF is part of the composite mixture. In contrast, the critical length is surpassed by only 4% of individually extracted single GF, whereas the combined presence of GF in the composite results in a notably higher percentage, at 19%. The tensile properties of these composites were investigated considering the effect of the hybridization by flax/glass short fibers. It was noted that the tensile properties of the hybrid composites increase comparing to the flax composites from 42.4 MPa to 53 MPa for the tensile strength and from 4.9 GPa to 5.4 GPa for the tensile modulus. In contrast, the elongation at break of the hybrid composites decreases from 1.7% to 1.5% with the incorporation of glass fibers. The experimental results were compared with the predictions of the mixture law and the Cox-Krenchel model. The findings indicate that mixing synthetic fibers with natural fibers is an excellent approach to enhancing mechanical properties.
{"title":"Investigation of the hybridization effect on mechanical properties of natural fiber reinforced biosourced composites","authors":"Nihel Ketata, Mohsen Ejday, Yves Grohens, Bastien Seantier, Noamen Guermazi","doi":"10.1177/00219983241255751","DOIUrl":"https://doi.org/10.1177/00219983241255751","url":null,"abstract":"Hybridizing the natural fibers with stronger synthetic fibers could significantly improve the properties of the natural fiber-reinforced composites. The improved mechanical capabilities of fiber reinforced polymers result from the fiber’s capacity for withstanding a more substantial portion of the mechanical load compared to the matrix it replaces. In order to guarantee the efficient transfer of the mechanical load from the matrix to the reinforcement, it is necessary to incorporate a fibrous filler. Transference takes place when the length of the fiber is longer than a specific critical length. Fibers which are shorter than the critical length will pull out from the matrix when tested to a tensile load. In some cases, complete transfer of the load is not performed. The goal of this study is to learn more about flax (FF), glass (GF), and mixtures of flax and glass (FF + GF) short fiber-reinforced PLA-PBS composites. This is performed to find out how the flax/glass combination affects the mechanical properties of PLA-PBS-reinforced short fiber composites. In order to extend their use for industrial applications, these composites were manufactured via extrusion and, afterward, injection molding. Fiber aspect ratios were followed after compounding and injection processing. The analysis of fiber lengths reveals a noteworthy observation: the proportion of fibers exceeding their critical length of 531 µm and 772 µm for FF and GF, respectively, is more significant when flax fibers (FF) and glass fibers (GF) are combined compared to when they reinforce the composite individually. Specifically, the composite containing both FF and GF exhibits a higher percentage of fibers surpassing their critical length, compared to their individual reinforcement in the composite. The results reveal that 27% of individually extracted single FF exceed their critical length, whereas a higher proportion, at 34%, is observed when FF is part of the composite mixture. In contrast, the critical length is surpassed by only 4% of individually extracted single GF, whereas the combined presence of GF in the composite results in a notably higher percentage, at 19%. The tensile properties of these composites were investigated considering the effect of the hybridization by flax/glass short fibers. It was noted that the tensile properties of the hybrid composites increase comparing to the flax composites from 42.4 MPa to 53 MPa for the tensile strength and from 4.9 GPa to 5.4 GPa for the tensile modulus. In contrast, the elongation at break of the hybrid composites decreases from 1.7% to 1.5% with the incorporation of glass fibers. The experimental results were compared with the predictions of the mixture law and the Cox-Krenchel model. The findings indicate that mixing synthetic fibers with natural fibers is an excellent approach to enhancing mechanical properties.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"66 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141152730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-21DOI: 10.1177/00219983241256335
Paolo Vannucci
The problem of obtaining anisotropic auxetic composite laminates, i.e. having a negative Poisson’s ratio for at least some directions, is examined in this paper. In particular, the possibility of obtaining auxeticity stacking uni-directional identical plies is considered. It is shown that if the ply is composed by isotropic matrix and fibers, then it is impossible to obtain totally auxetic orthotropic laminates, i.e. auxeticity for each direction, unless at least one among matrix and fibers is auxetic itself. Moreover, it is shown what are the conditions, in terms of the mechanical properties of the constituents and of the volume fraction of the fibers, to fabricate uni-directional plies with which to realize laminates having a negative Poisson’s ratio for some directions. Several existing materials are also examined. All the analysis is done using the polar formalism, very effective for the study of plane anisotropic problems.
{"title":"Anisotropic auxetic composite laminates: A polar approach","authors":"Paolo Vannucci","doi":"10.1177/00219983241256335","DOIUrl":"https://doi.org/10.1177/00219983241256335","url":null,"abstract":"The problem of obtaining anisotropic auxetic composite laminates, i.e. having a negative Poisson’s ratio for at least some directions, is examined in this paper. In particular, the possibility of obtaining auxeticity stacking uni-directional identical plies is considered. It is shown that if the ply is composed by isotropic matrix and fibers, then it is impossible to obtain totally auxetic orthotropic laminates, i.e. auxeticity for each direction, unless at least one among matrix and fibers is auxetic itself. Moreover, it is shown what are the conditions, in terms of the mechanical properties of the constituents and of the volume fraction of the fibers, to fabricate uni-directional plies with which to realize laminates having a negative Poisson’s ratio for some directions. Several existing materials are also examined. All the analysis is done using the polar formalism, very effective for the study of plane anisotropic problems.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"3 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141152735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-10DOI: 10.1177/00219983241251917
Mohammad Hassan Shaki, Yasser Rostamiyan, Seyed Masuod Seyedi
For the first time in this paper, a composite sandwich panel with a novel circular-shaped core reinforced with silica nanoparticles (SNPs) is designed and fabricated using the vacuum-assisted resin transfer molding (VARTM) method. Carbon fibers and epoxy resin are utilized to construct the composite sandwich panels, followed by polyurethane foam injection. After fabrication, the sandwich panels undergo uniform compression testing to examine their mechanical behavior and properties. In this study, the effects of various parameters, such as core length, core height, weight percentage (wt.%) of SNPs, and polyurethane foam, on the compressive strength of the structure are evaluated. To validate the results, a finite element simulation of the sandwich panel compression test is performed using ABAQUS software, and the results obtained are compared with experimental data, showing good agreement. The results of this research demonstrate that adding SNPs within a specific range results in a considerable enhancement of the structural strength. Adding SNPs up to 3% leads to approximately a 19% increase in the compressive strength of the structure. However, adding 4 wt.% SNPs results in a decrease of about 12% in the strength of the sandwich panel. Additionally, the core’s geometry significantly influences the control of compressive strength and rigidity of the sandwich panel. In other words, by increasing the core length, the compressive strength increases by 38%, while increasing the core height decreases compressive strength by about 30%. Also, it is found that adding polyurethane foam to the sandwich panel, despite a slight increase in weight, leads to a significant increase in compressive strength by about 32% and postpones its ultimate failure. Eventually, the hybrid specimen exhibits a strength approximately 57% greater than that of the pure foamless sandwich panel.
本文首次采用真空辅助树脂传递模塑（VARTM）方法，设计并制造了一种以二氧化硅纳米颗粒（SNPs）为增强材料的新型圆形芯材复合夹层板。碳纤维和环氧树脂被用于制造复合夹层板，然后注入聚氨酯泡沫。制作完成后，对夹层板进行均匀压缩测试，以检验其机械行为和性能。本研究评估了芯材长度、芯材高度、SNPs 重量百分比和聚氨酯泡沫等各种参数对结构抗压强度的影响。为验证结果，使用 ABAQUS 软件对夹芯板压缩试验进行了有限元模拟，并将所得结果与实验数据进行了比较，结果显示两者吻合良好。研究结果表明，在特定范围内添加 SNP 可显著提高结构强度。添加多达 3% 的 SNP 可使结构的抗压强度提高约 19%。然而，添加 4 重量百分比的 SNP 会导致夹芯板强度降低约 12%。此外，夹芯的几何形状对夹芯板抗压强度和刚度的控制也有很大影响。换句话说，增加夹芯长度，抗压强度会增加 38%，而增加夹芯高度，抗压强度会降低约 30%。此外，研究还发现，在夹芯板中加入聚氨酯泡沫，尽管重量略有增加，但抗压强度却显著提高了约 32%，并推迟了最终失效时间。最终，混合试样的强度比纯无泡沫夹芯板高出约 57%。
{"title":"Effects of core geometry, silica nanoparticles, and polyurethane foam on the mechanical properties of a novel circular-shaped core sandwich panels under compression test: Experimental study","authors":"Mohammad Hassan Shaki, Yasser Rostamiyan, Seyed Masuod Seyedi","doi":"10.1177/00219983241251917","DOIUrl":"https://doi.org/10.1177/00219983241251917","url":null,"abstract":"For the first time in this paper, a composite sandwich panel with a novel circular-shaped core reinforced with silica nanoparticles (SNPs) is designed and fabricated using the vacuum-assisted resin transfer molding (VARTM) method. Carbon fibers and epoxy resin are utilized to construct the composite sandwich panels, followed by polyurethane foam injection. After fabrication, the sandwich panels undergo uniform compression testing to examine their mechanical behavior and properties. In this study, the effects of various parameters, such as core length, core height, weight percentage (wt.%) of SNPs, and polyurethane foam, on the compressive strength of the structure are evaluated. To validate the results, a finite element simulation of the sandwich panel compression test is performed using ABAQUS software, and the results obtained are compared with experimental data, showing good agreement. The results of this research demonstrate that adding SNPs within a specific range results in a considerable enhancement of the structural strength. Adding SNPs up to 3% leads to approximately a 19% increase in the compressive strength of the structure. However, adding 4 wt.% SNPs results in a decrease of about 12% in the strength of the sandwich panel. Additionally, the core’s geometry significantly influences the control of compressive strength and rigidity of the sandwich panel. In other words, by increasing the core length, the compressive strength increases by 38%, while increasing the core height decreases compressive strength by about 30%. Also, it is found that adding polyurethane foam to the sandwich panel, despite a slight increase in weight, leads to a significant increase in compressive strength by about 32% and postpones its ultimate failure. Eventually, the hybrid specimen exhibits a strength approximately 57% greater than that of the pure foamless sandwich panel.","PeriodicalId":15489,"journal":{"name":"Journal of Composite Materials","volume":"21 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140938210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：