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This paper explores the production and mechanical analysis of hemp bi-grid cores designed for use in sandwich structures, using an ad hoc continuous manufacturing process. The proposed customised manufacturing process allows for the production of cores with varying density values (ranging from 0.37 to 0.63 g/cm3). Both graded cores, with varying fibre content through the thickness, and non-graded cores were produced. The mechanical properties of these cores were evaluated under flexural and compressive testing with specific flexural strength reaching approximately 80 MPa·cm3/g and specific compressive elastic modulus around 340 MPa·cm3/g. Additionally, to assess their impact performance in sandwich panels, hybrid panels with CFRP skins were fabricated and subjected to Low Velocity Impact tests at 25 J, 45 J and 50 J. The results revealed that optimizing core density had increasingly beneficial effects as the impact energy increased. These findings suggest that the possibility of customising failure modes and tailor energy absorption capabilities of the proposed structures open the way for new, exciting perspectives for the development of innovative sandwich structures, broadening the application of natural fibres in various industrial sectors. [ABSTRACT FROM AUTHOR]

The use of waste‐based bio‐fillers in composite manufacturing has increased in recent years due to their sustainable and biodegradable characteristics. The current study fabricates jute/banana (JB) fiber‐reinforced epoxy composites incorporating waste‐derived eggshell (ES) bio‐filler and investigates the effect of ES bio‐filler on the mechanical, morphological, and water absorption properties of the composites. JB fibers (1:1) and varying ES filler contents (5, 10, 15, and 20 wt%) were used to manufacture the composites using the hand lay‐up technique. Their tensile, flexural, and impact properties, microstructure, chemical compositions, and water absorption are then examined. It is found that the composite composed of 15 wt% ES exhibits better tensile and flexural properties with a tensile modulus and strength of 4.42 GPa and 95.27 MPa, and a flexural modulus and strength of 3.96 GPa and 117.47 MPa, respectively, whereas the composite filled with 5 wt% ES shows a maximum impact strength of 46.83 kJ/m2 and drops with increasing bio‐fillers. Scanning electron microscopy reveals that composite failures occur due to jute and banana fiber fractures, filler–fiber‐matrix debonding, fiber pullout, and ES filler agglomeration. Moreover, water absorption reduces as the ES content rises, and the 20 wt% ES filler‐based composite shows a minimum water absorption of 7.67% after 240 h. This study provides some insights to promote the usage of ES bio‐filler in natural fiber composites to improve their mechanical and water absorption properties and their potential applications in the internal structures of automobiles, aircraft, and construction. [ABSTRACT FROM AUTHOR]

Copper (Cu)-based hybrid composites were fabricated by powder metallurgy, incorporating Graphite (Gr) and Carbon nanotube (CNT) reinforcements at various fractions. The composites were formed using a cold pressing technique and subsequently sintered at various temperatures. The structural properties of the hybrid composites were evaluated using Scanning Electron Microscopy (SEM), Energy Dispersion Spectrum (EDX) and X-ray diffraction (XRD). Hardness, compression, wear and corrosion tests were performed to show the effect of the reinforcements. It was shown that the hardness of Gr and CNT reinforcements have significantly improved the properties of pure Cu. The Cu-Gr-2CNT hybrid composite, which was subjected to sintering at a temperature of 850°C, exhibited the highest level of hardness, showing a significant increase of 51.4% in comparison to the pure Cu sample. While the compressive stresses increased in the Cu matrix with the addition of Cu-Gr, it increased to 350 MPa with the addition of 2 wt% CNT. The hardness value exhibited a similar increase and was measured to be 122 HV in Cu-Gr-2CNT. During the wear tests, the coefficient of friction values fell by 9.2% for Cu-2CNT, by 3.88% for Cu-CNT, by 3.92% for Cu-Gr-2CNT, and by 5.27% for Cu-Gr-CNT, as compared to pure Cu. The comprehensive findings demonstrated that the tests and analyses yielded consistent results, and the utilization of various combinations of Gr and CNT reinforcements enhanced the mechanical, tribological, and corrosion resistance properties of the fabricated hybrid composites. Nevertheless, the combination of Cu-Gr-2CNT yielded the most advantageous outcomes. [ABSTRACT FROM AUTHOR]

Highlights Wind turbines are subjected to extreme weather and load conditions; hence, high strength and impact resistance are required. Furthermore, wind turbine blades can be subjected to impact loads such as bird strikes, resulting in the formation of microcracks. Self‐healing capsules can be used to mend turbine blades for microscale damage. The incorporation of self‐healing capsules may cause a decrease in the mechanical characteristics of the composites prior to impact resistance, which can be compensated for with efficient fillers such as silicon carbide whiskers (SiCw). Thus, a novel hybrid composite structure is examined with the advantage of using a self‐healing mechanism and SiCw reinforcement. Tensile, tribological, and Charpy impact tests were performed to characterize the mechanical and tribological properties, which were supported with microscopic observations. Multiple experimental characterizations were performed to investigate the impact, and the ultimate tensile strength (UTS) and energy absorption capacity of the structure were shown to increase by 32% and 45%, respectively, with the addition of SiCw. The presence of self‐healing agents provides a 5% rise in UTS after enough time for healing following the collision. The structure's tribological performance is improved by 10% in wear resistance and 20% in friction coefficient. Hybrid laminated composite structure with silicon carbide whisker and self‐healing capsules. Tensile and Charpy impact tests conducted with microscopic observations Increased ultimate tensile strength and energy absorption capacity by 32% and 45%. Tribological improvement by 10% in wear resistance and 20% in friction coefficient. [ABSTRACT FROM AUTHOR]

Hybrid kenaf/glass fiber reinforced polymer composites have emerged as promising structural materials, garnering significant attention due to their unique blend of natural kenaf fibers and synthetic glass fibers. However, despite their potential, there remains a gap in the comprehensive understanding of their quasi‐static mechanical behavior, creep resistance, and fatigue performance. This paper addresses this gap by presenting recent advancements in studying these key properties of hybrid composites. Studies reveal that the combination of kenaf and glass fibers results in enhanced tensile, flexural, and impact strengths compared to individual fiber composites. Additionally, the hybridization offers improved creep resistance, with the glass fibers reinforcing the polymer matrix against deformation under sustained loads. Furthermore, investigations into fatigue properties demonstrate the resilience of hybrid composites to cyclic loading, contributing to prolonged service life in high‐stress environments. By elucidating the interplay between kenaf and glass fibers, this review underscores the potential of hybrid composites in various structural applications. The synergistic effects between natural and synthetic fibers offer a balance between sustainability, performance, and durability, making hybrid kenaf/glass fiber reinforced polymer composites a compelling choice for industries seeking lightweight, high‐performance materials in which aligns with the sustainable development goals (SDGs) especially on Goal 12. Highlights: In composite engineering, combining glass and kenaf fibers could cut production costs, yield high‐performance materials, and promote green technology.Substituting part of the glass fiber with kenaf can enhance the strength‐to‐weight ratio and promote greater biodegradability in current synthetic composites.Quasi‐mechanical properties of hybrid kenaf/glass‐based composites was enhanced by optimal stacking sequences, filler addition, and fiber treatment.Failures due to fatigue and creep can be reduced by hybridizing kenaf/glass fiber composites can prevent in polymer composite due to enhance elastic modulus.Enhanced tribological performance of hybrid kenaf/glass‐based composites due to less damage in microstructure via good interlocking of kenaf and glass in matrix. [ABSTRACT FROM AUTHOR]

The interest in bio-based polymer composites is brought about by the quest for sustainable environmentally friendly materials due to the rapid depletion of petroleum resources and the desire to find solutions to environmental pollution because of synthetic composites. The purpose of this work was to study the effect of various treatments on the performance and potential use of hybrid barkcloth-banana fiber-reinforced polyester resin biocomposites particularly for interior automotive applications. Two categories of biocomposites were prepared: (1) untreated banana fibers and barkcloth, denoted by A1, B1, C1, D1, and (2) 5% sodium hydroxide (NaOH) treated banana fibers and barkcloth with nano-cellulose denoted by A, B, C, and D. Banana fibers were soaked in the alkali solution for 12 h, nanocellulose was extracted from the barkcloth using the acid hydrolysis method and applied to the barkcloth fabrics by the pad-dry-cure method with a concentration of 1% nanocellulose. The treated barkcloth had better bonding capacity with the resin and was thermally stable than the untreated barkcloth. In contrast, the alkali treatment of banana fibers led to fiber degradation, making them brittle and consequently reducing their tensile and bending strength. The mechanical properties of both composites showed that sample D1 had the best tensile and flexural strength attributed to the fact that it was based on the untreated banana fibers as opposed to the degraded alkali-treated banana fibers. [ABSTRACT FROM AUTHOR]

This work presents the experimental results of a quasi-static penetration test of laminates on a polyurea-polyurethane matrix, reinforced with aramid, carbon and flax fibers. A total of 15 series of samples with different reinforcement configurations were prepared. A quasi-static penetration test was performed for coefficient SPR = 5. The SPR = Ds/Dp was calculated as the ratio of the support hole diameter (Ds) to the punch diameter (Dp). A punch with a rounded 9-mm diameter tip was used to penetrate the material. Percentage changes of penetration energy (%E) and maximum load (%P) compared to a non-hybrid laminate were calculated in order to estimate the impact of hybridization on the properties of laminates. The energy absorbed during the quasi-static penetration test was used to calculate the PSS (punch shear strength) of the laminates. Damage analysis was performed after the puncture test. It was observed that both the type of reinforcement and the configuration of the reinforcement layers have a potential impact on the obtained results and the laminate damage mechanism. [ABSTRACT FROM AUTHOR]

Epoxy resin (EP) is widely employed in power systems and electronic devices due to its low cost and easy processing along with good insulative and adhesive properties. However, EP insulation properties are compromised at elevated frequencies and temperatures because of its negative temperature coefficient effect (NTC) and poor thermal characteristics. In this context, barium strontium titanate (BST‐60), a positive temperature coefficient (PTC) filler, and hexagonal boron nitride (h‐BN), a thermally conductive filler, both surface‐modified with dopamine, are added in EP to simultaneously improve thermal and dielectric insulation properties at high temperatures and high frequencies. This study finds that below the Curie point of BST, the insulating properties of h‐BN fillers significantly contributes to improving insulation properties. Conversely, above the Curie point, the insulating nature of BST fillers leads to an improvement in the insulation performance of composites. Furthermore, at elevated frequency and temperature, the nano h‐BN enhances thermal conductivity of EP by establishing a thermally conductive network, while micro‐BST suppresses the NTC effect of EP by regulating electrical resistivity above the Curie point. The Heywang model elucidates the PTC effect of BST fillers, while a proposed heat conduction‐dissipation mechanism explains the behavior of incorporated fillers at different temperatures. Highlights: PDA‐modified Ba0.8Sr0.2TiO3 and h‐BN co‐doped epoxy composites are prepared.Negative temperature coefficient effect of epoxy is mitigated by PTC fillers.The optimal wt.% of filler enhances both dielectric and thermal properties.Dielectric properties are explored at high frequencies and temperatures.Optimized epoxy composites are suitable for high‐frequency applications. [ABSTRACT FROM AUTHOR]

The new generation of hybrid aluminum matrix composite was targeted to meet the yearnings of advanced engineering application which it does through improved physical, mechanical, tribological, and microstructural properties. The performance of this composite depends on the reinforcing materials selected and combined, the processing technique adopted in synthesizing the hybrid composites and processing parameters selected during the composite synthesis. This study tends to review different types of eco-friendly materials combined with synthetic materials to synthesize this new generation of hybrid composites. Perhaps, their influence on the physical, mechanical, tribological, and microstructural behavior of the synthesized composites through stir casting technique. Furthermore, research areas which could further enhanced hybrid aluminum matrix composites production with suggested enhancement were looked into for future application in engineering sector. [ABSTRACT FROM AUTHOR]

The current study attempts to explore the crystallographic, rheological and, dynamic mechanical properties of the submicron‐treated cenosphere (t‐ CSF) particles and sisal fiber (SF) reinforced Styrene‐(Ethylene‐Butylene)‐Styrene (SEBS) toughened PP hybrid composites. Moreover, the composites reinforced with 25 wt.% of SF and 5 wt.% of CSF (Treated 6 wt.% cetrimonium bromide (CTAB)) demonstrated the most significant storage modulus (E′), loss modulus (E"), and lowest damping (tan δ) factor throughout the temperature range. Likewise, X‐ray diffraction techniques were used to assess the samples' crystallographic properties. The composites reported an enhanced β phase (responsible for high impact strength and reduced α phase of the base matrix compared to pristine PP. Likewise, all the composites' rheological properties showed an improved complex viscosity (η*) compared to the BM but lower than that of the pristine PP. Overall processing parameters of the BM and composites were improved due to the decrement in the η* of all the composites. The rheological properties confirmed the easy processing of the fabricated composites due to the improved flowability. The storage (G′) and loss (G") modulus of all the composites were desirably higher than that of the BM. [ABSTRACT FROM AUTHOR]

This study focused on the development of environmentally friendly epoxy-based biocomposites by incorporating bamboo fiber (BF) and calcite particles (CP) as reinforcements. A total of 125 specimens were fabricated with different weight percentages of BF and CP ranging from 0% to 15% to the epoxy. The biobased reinforcements were processed before incorporation, and the hand layup technique was used to fabricate the composites, which were then cured at ambient temperature. Evaluations of selected properties were carried out to ascertain the most probable areas of application, while the fracture surfaces were examined using SEM. The results indicated that the inclusion of these hybrid bio-reinforcements significantly enhanced the properties of the biocomposites compared to unreinforced samples. The optimal composition was identified as 12 wt% BF/CP, which demonstrated the highest ultimate tensile strength (32.84 MPa) and tensile modulus (1.9 GPa), attributed to the strong interfacial bonding between the epoxy matrix and the BF/CP reinforcements. Additionally, the flexural strength (55.38 MPa) and modulus (2.72 GPa) were improved due to the effective load transfer and stiffening effect of the calcite particles. The hardness (67 HS) and wear index (0.015 mg) were enhanced by the toughening mechanism provided by the bamboo fibers, while the density (1.195 g/cm³) remained within a desirable range for lightweight applications. Composites with 9 wt% BF/CP exhibited the highest impact strength (22.66 J/m2), likely due to the optimal balance of fiber-matrix interaction and energy absorption capacity. These findings indicate that the developed hybrid-reinforced biocomposite compositions hold great promise with the improved physical and mechanical properties as seen and can be utilized for various applications, including automotive, aerospace, and other engineering applications. [ABSTRACT FROM AUTHOR]

The incorporation of filler materials to enhance the properties of fibre-reinforced plastics is a prevalent practise in materials science. Calcium carbonate is a commonly used inorganic filler in composite fabrication. Eggshell, a rich source of calcium carbonate, offers an organic alternative to conventional inorganic fillers. This study investigates the efficacy of different types of eggshells as filler materials. Three variants, viz., unhatched raw eggshell, unhatched boiled eggshell, and post-hatched eggshell, were used to fabricate composite variants, which were then subjected to mechanical characterization and compared with unfilled composites. The results indicated that composites filled with unhatched eggshells outperformed those with post-hatched eggshells. Tensile testing revealed a significant enhancement in the tensile properties of all eggshell-filled composites in comparison to the unfilled ones. The composite variant filled with unhatched raw eggshell filler showcased the utmost tensile modulus and strength, with a notable 36% improvement in comparison with the unfilled variant. Similarly, flexural tests demonstrated a 53% increase in flexural strength for unhatched raw eggshell-filled composites over unfilled composites. SEM imaging confirmed these findings by showing crack arrests, deviations, particle distribution, and strong interfacial bonding in the eggshell-filled composites. [ABSTRACT FROM AUTHOR]

In the present work, hybrid composites made of Al2214 alloy with B4C and graphite were produced by using a liquid metallurgical process. Al2214 alloy was utilized to create hybrid composites that had 1.5–6 wt% of B4C particles and a constant 3 wt% of graphite particles. Microstructural analysis using scanning electron microscope (SEM), energy dispersion spectroscopy (EDS), and X‐ray diffraction (XRD) was done on the produced composites. The density, hardness, ultimate, yield strength, and elongation as a percentage were carried out using ASTM E8 for tensile and E10 standard for hardness test. The wear behavior of Al2214‐B4C and graphite composites was examined as per ASTM G99 standard using a wear testing device under a variety of loads and rotation speeds. Graphite and boron carbide particles were equally dispersed throughout the Al2214 alloy, according to SEM photographs. Graphite and B4C particles were detected in the Al2214 alloy by EDS and XRD analyses. The density of Al alloy composites was decreased by adding dual particles to the matrix. The Al2214 alloy's hardness, ultimate strength, yield strength, and wear resistance were all enhanced by the inclusion of dual particles, which increased these properties by 15.4%, 40.4%, and 46.7%, respectively. The presence of hybrid particles in the Al2214 alloy was revealed by EDS and XRD patterns. The density of Al alloy composites was decreased by adding dual particles to the matrix. Tensile force micrographs provided further evidence of the unique fracture behaviors shown by the Al2214 alloy and its composites. In order to examine the wear mechanisms and different morphologies of worn surfaces, scanning electron micrographs were taken. [ABSTRACT FROM AUTHOR]

Natural fiber-based composites become more popular as the demand for lightweight, high-strength materials for specialized applications grows. Moreover, natural fiber-based composites have greater durability, stiffness, and damping resistance. Researchers developed a wide variety of composites for different applications. This study aims to develop a hybrid composite using Acacia arabica and Sida cordifolia fibers as a reinforcement and epoxy as a resin. The fibers were treated using 5% NaOH solution. Six samples were prepared by varying the proportion of fibers and resin. The performance of the composites was measured by conducting the tensile, flexural, impact, and hardness tests. The alkaline-treated sample with 70% fiber and 30% resin (S6) exhibits a greater tensile strength of 384 MPa which shows much improvement in tensile strength when compared to other samples. The mechanical properties of the hybrid composites are better than many other composites available in literature. The surface morphological analysis and water absorption tests were also carried out. [ABSTRACT FROM AUTHOR]

This paper presents the theoretical investigations on the free and forced vibration behaviours of carbon/glass hybrid composite laminated plates with arbitrary boundary conditions. The unknown allowable displacement functions of the physical middle surface are expressed in terms of standard cosine Fourier series and sinusoidal auxiliary functions to ensure the continuity of the displacement functions and their derivatives at the structural boundaries. Arbitrary boundary conditions are achieved through the introduction of an artificial spring technique. The first shear deformation theory and Lagrange equations are utilized to derive the energy expression, and the eigenvalue equations associated with free and forced vibration are obtained by Rayleigh-Ritz variational operations. Subsequently, these equations are then solved to determine the natural frequency, mode of vibration, and the steady-state displacement response under forced excitation. The new results are compared with those from references and finite element methods to verify the convergence, accuracy and efficiency of the analytical method. The effects of hybrid ratios, stacking sequences, lamination schemes, fibre orientation, boundary conditions and excitation force on the free and forced vibration behaviours of the carbon/glass hybrid composite laminated plates are analyzed in detail. [ABSTRACT FROM AUTHOR]

Composite materials are combinations of distinct materials, engineered to create new materials with specific properties. Stir-casting method is used to prepare composites, it involves heating Aluminium Alloy (Al 8011) reinforced with B4C (Boron Carbide) and fly ash at 5, 10, and 15vol.%. The molten material is poured into a die to prepare the samples for testing. The composite’s density is measured by the principle of Archimedes, which decreases as the reinforcing particles increase, and then density and porosity are compared. The wear test specimen was prepared as per standard. The design model is generated by applying the RSM (Response Surface Methodology) equation with various parameters like load, sliding velocity of the pin, and track distance with values of 1–2kg, 1.5–2.5m/s, and 1000–3000m, respectively. The developed ANOVA (Analysis of Variance) result suggests that the created model is significant. The validation test was run and the results showed mean value of 0.0021356 and this value is in the 95% prediction range. The SEM (Scanning Electron Microscope) images of wear-tested composite show the delamination layers and deep groves. EDS (Energy Dispersive Spectroscopy) is used with electron microscopes to determine the chemical composition of wear out specimens. By the end of this study, it is discovered that the wear rate lowers with increasing reinforcement percentage while increasing with load and sliding velocity. [ABSTRACT FROM AUTHOR]

This study looks at how erosive wear affects hybrid composites made by vacuum infusing glass and basalt fibers into an epoxy matrix. The study uses garnet abrasives and a design experiment method to test how resistant these hybrid composites are to erosion at 30°, 60°, and 90° angles of impact. The analysis included three‐dimensional profilometry and scanning electron microscopy. Results show that glass layers enhance erosion resistance, whereas basalt layers increase wear. Key quantitative findings include erosion rates and mass loss, highlighting impingement angle and erosion time as critical factors. At a 30° angle, basalt exhibited more severe wear (erosion rate: 0.8090 mg/g for 20 s) compared to glass (erosion rate: 0.5683 mg/g). Conversely, at 90°, the erosion rate for basalt decreased to 0.3643 mg/g, indicating a decreased sensitivity to this steeper angle. According to the ANOVA, impingement angle and erosion time account for 30.08% and 50.25% of the erosion rate variance, respectively. These findings advance our understanding of material behavior in hybrid composites and emphasize the strategic selection and layering of materials for enhanced durability. This research contributes to developing more sustainable composites, demonstrating natural fibers' potential to improve mechanical properties and erosion resistance. Highlights: Glass layers enhance durability against erosive forces in hybrid composites.Basalt layers accelerate erosion rates, showing a need for strategic layering.Glass fiber reinforcement significantly improves wear performance.Hybrid constructions with glass a top basalt balance flexibility and durability.Emphasizes eco‐friendly advantages of natural materials in composites. [ABSTRACT FROM AUTHOR]

The composite powder containing Al3Ni and Al3Ni2 intermetallic compounds was obtained by vacuum synthesis to reinforce the aluminum matrix of the developed composite. For this purpose, nickel and aluminum powders were mixed in a ball mill, followed by heating the resulting mixture in vacuum to 650 °C to initiate an exothermic reaction between the powder components. To obtain an Al–Al3Ni composite, the synthesized composite powder and matrix aluminum powder were mixed in a mill, followed by compacting the resulting mixture and sintering the obtained samples in vacuum. It has been found that vacuum synthesis results in the formation of a composite powder with heterogeneous phase composition, including Al3Ni, Al3Ni2, Al4C3, and Al. Carbon formed as a result of thermal decomposition of stearin on the surface of aluminum particles reacts with aluminum to form aluminum carbide. After sintering the compacted mixture of aluminum and composite powders, a composite reinforced with Al3Ni and Al4C3 phases is formed. Tribological tests have shown that the obtained composite is a promising wear-resistant material with hybrid reinforcement by intermetallic and carbide phases. [ABSTRACT FROM AUTHOR]

A novel hybrid polyester composite comprising jack tree and jute fibers reinforced with eggshell filler is presented addressing the global need for sustainable alternatives to synthetic materials. The comprehensive analysis of physical and mechanical properties, such as tensile strength, impact resistance, hardness, water uptake was carried out using Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM). The manual hand layup technique was employed to ensure reproducible composite production. The resulting materials exhibited favorable mechanical properties, with the tensile strength and elongation balanced between jute and jack tree fibers, augmented by the reinforcing effect of the eggshell filler. Jack tree fibers significantly enhanced impact strength, contributing to the overall toughness of the composite. Hardness testing revealed higher crystallinity attributed to jack tree fibers. Water absorption characteristics demonstrated a nuanced interaction between cellulose abundance and fiber mass. FTIR spectroscopy provided molecular insights, while SEM analysis visually depicted the intricate structure of the composite. The amalgamation of jack tree and jute fibers with an eggshell filler not only enhances mechanical prowess but also aligns with global environmental efforts. This research advances sustainable composite materials, offering nuanced insights into the interplay between natural fibers, fillers, and matrices, with implications for eco-friendly solutions in diverse industries. The findings contribute to a greener, more sustainable future in industrial applications. [ABSTRACT FROM AUTHOR]

Recent achievements in engineering include the development and production of hybrid aluminium metal matrix composites (AMMCs), which are widely employed in all automotive applications due to their significant weight reduction and better strength compared to the base metal used in various manufacturing processes. The present work used burnt sugarcane bagasse powder (SCBP) as the filler material in aluminum–alumina composite. This filler material is inexpensive, low in density, accessible and widely available, renewable and ecologically innocuous. The fabrication of various AMMCs has been implemented using SCBP and alumina at different weight percentage ratios by powder metallurgy process. The validity of elemental composition is tested using energy-dispersive X-ray analysis, X-ray fluorescence, X-ray diffraction and CHNS studies. The specimens are made using an Instron machine at a pressure of 474 MPa and sintered for various lengths of time and temperatures. All specimens were checked for microhardness, uniaxial compression and fractography using the FMV1-MC-AT model, the Instron 8801 MT model, and the JEOL JSM-7001F model, respectively. The outcomes were compared with the base composite. At 600°C and for 2.5 h with 3 wt% burned SCBP, it was observed that relative density, microhardness and ultimate compression strength improved by 1.98, 28.18 and 24.27%, respectively. [ABSTRACT FROM AUTHOR]

Glass fiber/polymer composites are widely utilized in many structural applications because of their high specific strength and stiffness-to-weight ratios. In this study, woven glass fiber/epoxy was hybridized with short glass fibers of different lengths (2, 4, 6, 2+4, 2+6, and 4+6 mm) and contents (3, 6, 9, and 12 wt%) to produce hybrid woven SGF/epoxy composites. Variations in the thickness, fiber volume fraction, density, and void content of the prepared composites were determined. Mechanical tests such as tensile and Charpy impact tests were conducted. Compared to the woven fabric composites without short glass fibers (control samples), the tensile strength increased by approximately 13% at an optimum weight fraction of 3 wt% using short glass fiber lengths of 4 mm. Meanwhile, the incorporation of short glass fibers into the woven glass composites decreased the tensile modulus for all lengths. The maximum enhancement in the impact strength (approximately 14%) was achieved by the hybrid composite samples reinforced with 4 mm of short glass fibers at 3 wt%. This hybrid composite offers 18% and 20% improvements in the specific tensile and impact strengths, respectively. In summary, filling the woven fabric composites with specified short fiber contents and lengths can increase their mechanical performance when resin-rich regions are reinforced with short fibers without forming relatively thick interleaves between the woven fabric plies. [ABSTRACT FROM AUTHOR]

The increasing demand for environmental and sustainable materials has motivated efforts to fabricate biocomposites as alternatives to conventional synthetic fiber composites. However, biocomposite materials have some drawbacks such as poor mechanical resistance, fiber/matrix incompatibility, low thermal resistance and high moisture absorption. Extensive research has been conducted to address these challenges, in terms of the sustainable production, serviceability, reliability and properties of these novel biocomposites. Silk fibers have excellent biocompatibility and biodegradability along with moderate mechanical properties, while flax fibers have a high specific strength and modulus. The combination of the silk fiber with moderate modulus and stiffness with flax fibers with high specific strength and modulus allows the modulation of the properties of silk using the intra- and inter-hybridization of both fibers. In this study, silk and flax fibers are combined in different arrangements, totaling eight different composites; the quasi-static mechanical properties and dynamic mechanical thermal analysis are discussed, focusing on the structure versus relationship properties, with the aim of corroborating the freely available data from literature. The main findings indicated that the synergic effect of the flax fiber and silk fiber leads to a tailormade composite with a low cost and high performance. [ABSTRACT FROM AUTHOR]

Integrating nanomaterials like carbon nanotubes (CNTs) and iron oxide (Fe3O4) into epoxy composites has attracted significant interest due to their potential to enhance mechanical properties. This study evaluates the impact of dispersion quality on the mechanical performance of CNT/Fe3O4/epoxy composites, comparing stirring and sonication methods at three different loadings: 0.1, 0.3, and 0.5 wt.%. Tensile testing revealed that sonicated composites consistently outperformed stirred composites, with a significant increase in the elastic modulus and ultimate tensile strength (UTS). However, fracture strain decreased in both composite types compared to pure epoxy, with sonicated composites experiencing a more significant reduction than stirred composites. These results underscore the importance of high-quality dispersion for optimizing mechanical properties. [ABSTRACT FROM AUTHOR]

It is now widely accepted that various subsets of hybrid fiber composites reinforced with combined natural and synthetic fibers can significantly expand the applicability of composite-based materials in design and technology practice. The already existing unnatural circumstances on the planet put natural fibers far ahead of traditions in the field of materials thanks to their biodegradability characteristics, availability and over-term endurance and corrosion resistance. At the same time, composites are rapidly taking their place in many industries and sectors of the economy as metals in as much as it is economically and energetically justified. This study evaluates the mechanical properties of hybrid composites reinforced with glass, hemp, and sisal fibers. Using a hand lay-up method with epoxy resin, composite laminates were fabricated and tested for tensile, flexural, impact strengths and hardness test in accordance with ASTM standards. The experimental results revealed that glass-sisal fiber composites achieved the highest tensile strength of 69.1 MPa, while glass-hemp-sisal fiber composites exhibited superior flexural strength of 15.22 MPa and impact strength of 137.45 kJ/m2 while best hardness value was 24.73 HV for glass-sisal fibre composite. These findings underscore the potential of glass-sisal-hemp fiber-reinforced epoxy composites as viable alternatives to traditional synthetic fiber-reinforced materials in automotive industry where there are no structural loadings i.e. automobile interiors; offering enhanced mechanical performance and sustainability.

This work presents the experimental results of a quasi-static penetration test of laminates on a polyurea-polyurethane matrix, reinforced with aramid, carbon and flax fibers. A total of 15 series of samples with different reinforcement configurations were prepared. A quasi-static penetration test was performed for coefficient: SPR=5. The SPR= Ds/Dp was calculated as the ratio of the support hole diameter (Ds) to the punch diameter (Dp). A punch with a rounded 9-mm diameter tip was used to penetrate the material. Percentage changes of penetration energy (%E) and maximum load (%P) compared to a non-hybrid laminate were calculated in order to estimate the impact of hybridization on the properties of laminates. The energy absorbed during the quasi-static penetration test was used to calculate the PSS (punch shear strength) of the laminates. Damage analysis was performed after the puncture test. It was observed that both the type of reinforcement and the configuration of the reinforcement layers have a potential impact on the obtained results and the laminate damage mechanism.

Composite materials made from natural ingredients are currently being developed by researchers as materials that are more environmentally friendly. Hybridization techniques used in making composite materials continue to progress, involving the combination of several raw materials with similar or different properties, such as organic/organic, organic/inorganic, and inorganic/inorganic. In this research, coconut fiber which is an organic material is combined with fly ash which is an inorganic material. The contrasting properties of these two raw materials prompted the evaluation of their combination by including a silane coupling agent, which facilitates the bonding of organic and inorganic components. The essence of this research is to test the effect of adding silane coupling material on several parameters, namely physical properties (density, water absorption, and thickness swelling), mechanical properties (tensile strength, tensile modulus, elongation, and flexural strength), and thermal properties. To prepare coconut fiber, alkaline treatment is used to remove hemicellulose and lignin. Then, the coconut fiber was soaked in a 5 % vinyltrimethoxysilane (TVS) solution by weight. The addition of silane coupling material affects the physical properties of the composite resulting in a decrease in water absorption by 33 % and a decrease in thickness swelling by 0.3 %. The inclusion of silane coupling agent led to an increase in tensile strength, tensile modulus, and flexural strength, while elongation decreased by 20 %. Thermal properties analysis showed that the silane treatment affected the decomposition of the composite material, reducing it by 2 % from 90 % without the coupling agent to 88 % with the coupling agent.

A hybrid Mg composite filled with micro Al2O3 and nano TiO2 is manufactured through a blend press sinter powder metallurgy route. To appraise the significance of filler incorporation on the mechanical and corrosion strength, the composite is undergoing a series of characterizations. Initially the filler distribution was analyzed through electron microscopes. Static mechanical tests as per ASTM are conducted to measure the influence of fillers on the tensile and compression properties. The corrosion characteristics were studied by immersing the composites into the laboratory synthesized stimulated body fluid (SBF). Through the Tafel Polarization, the corroded surfaces are examined. The corrosion resistance of the composites exhibited a change that closely resembled that of pure magnesium. Based on the experimental findings, it appears that the composite being examined is well-suited for various biomedical applications, particularly in the field of dental implants.

The ongoing research focuses on exploring the potential of Careya arborea (CA) fiber, banana fiber (BF), and epoxy composites as sustainable alternatives to petroleum-based products and synthetic fibers. The aim is to enhance the interfacial bonding and overall performance of these composites while reducing reliance on traditional materials. The study investigates the adhesion between CA fiber, BF (both chemically treated), and epoxy with polylactic acid (PLA) coating. Specifically, it examined how the PLA coating affects the mechanical properties, including tensile strength, flexural strength, impact resistance, and water absorption behavior, of the fabricated composites. Mechanical characterizations of the composite specimens are conducted following ASTM standards. The PLA-coated and NaOH-treated specimens significantly improved their tensile strength (20.56%) and flexural strength (16.7%), and significantly reduced their water absorption capacity (by 47.6%) compared to the untreated ones. These findings highlight the promise of using treated natural fibers and PLA coatings to create more sustainable and high-performance composite materials.

Hybrid composites comprising conducting nanowires (NWs) and insulating particulate fillers exhibit varying trends in their electrical conductivity based on the conditions of the constituent fillers. This study presents a quantitative model that comprehensively describes these changes, encompassing both increasing and decreasing trends. The model is formulated as an equation with two parameters quantifying the excluded volume effect and the NW bending effect, which are considered the primary factors determining NW network morphology in the composites. The influence of the parameters on the electrical conductivity of hybrid composites is analyzed with respect to the size and content of the constituent fillers using Monte Carlo-based simulations and statistical regression techniques. Numerical investigations reveal that distinct conductivity patterns under various particulate filler dimensions result from the interplay of these effects. The proposed model, validated through 2-D and 3-D simulations, effectively captures these complex interactions across diverse configurations of the constituent fillers.

The present work examines the tribological characteristics of cast aluminium–silicon matrix composites reinforced with silicon carbide (SiC) and graphite (Gr). The metal matrix composite samples were manufactured using stir and squeeze casting techniques, employing an Al–Si matrix alloy and integrating particulate SiC and varying quantities of graphite particles. To investigate the impact of varying amounts of graphite on the Al/SiC composite, graphite particles were included at volumetric proportions of 5, 7.5 and 10%. Before being integrated into the matrix, Cu-coating was employed on graphite particles using electroless coating to enhance the adhesion with the matrix composition. Tribological experiments were conducted on Al/SiC and the Al/SiC/Gr composites using a pin-on-disc tribometer apparatus. Al–SiC and Al/SiC/Gr samples were specifically engineered and employed as a pin, while AISI 8620 steel was utilized as a disc. Adding graphite particles to the Al/SiC composite decreased the amount of wear and friction. The utilization of hybrid Al/SiC/Gr composites resulted in the creation of tribo-layers during sliding, hence minimizing the occurrence of grooves, plowing and smearing. [ABSTRACT FROM AUTHOR]

The increasing demand for environmental and sustainable materials has motivated efforts to fabricate biocomposites as alternatives to conventional synthetic fiber composites. However, biocomposite materials have some drawbacks such as poor mechanical resistance, fiber/matrix incompatibility, low thermal resistance and high moisture absorption. Extensive research has been conducted to address these challenges, in terms of the sustainable production, serviceability, reliability and properties of these novel biocomposites. Silk fibers have excellent biocompatibility and biodegradability along with moderate mechanical properties, while flax fibers have a high specific strength and modulus. The combination of the silk fiber with moderate modulus and stiffness with flax fibers with high specific strength and modulus allows the modulation of the properties of silk using the intra- and inter-hybridization of both fibers. In this study, silk and flax fibers are combined in different arrangements, totaling eight different composites; the quasi-static mechanical properties and dynamic mechanical thermal analysis are discussed, focusing on the structure versus relationship properties, with the aim of corroborating the freely available data from literature. The main findings indicated that the synergic effect of the flax fiber and silk fiber leads to a tailormade composite with a low cost and high performance.

The observation of fibers in salvadora persica roots inspired us to consider the idea of using them as reinforcement to create an innovative composite. The current work focuses on the volumetric mass density, extraction, molding, and mechanical testing of composites and hybrid composites made from salvadora persica roots and glass fibers reinforced with two types of polyester matrix, chosen due their characteristics suitable for use in different orientations. Various extraction and combination methods have been used to identify an optimal approach for obtaining fibers from salvadora persica roots, considering its chemical composition (hemicellulose, pectin, and lignin). In this investigation, the hand lay-up method was used to mold specimens with different geometries. The composite and hybrid composite were combined with a polyester matrix and subjected to various mechanical tests namely; tensile, impact resistance, and water absorption. The results indicate that reinforcing polyester resins with SP fibers, whether long or short, enhances the overall mechanical properties of the composite. Additionally, improved adhesion between salvadora persica roots fibers and resin was observed.

Highlights Compression molded hybrid laminates have been manufactured by stacking 10 recycled epoxy‐based carbon fiber plies with interlaminar polyamide film of 50 μm thickness. At first, carbon fiber (CF) reinforced composites underwent thermo‐mechanical disassembly to obtain single composite CF plies. These plies, still impregnated with the waste cured resin, have been re‐assembled by interposing one or two sheets of the thermoplastic film in the lamination sequence. Neat laminates have been used for comparison. Samples of size 85 × 30 mm2 have been tested under bending load, and materials repairability has been evaluated under 2 consecutive repairing cycles that have been carried out by applying pressure and heat along the composite failure line. Even though the neat composite showed the best mechanical properties, after the first repairing cycle a drastic drop has been recorded with a reduction of the elastic modulus of 92.4%. On the other hand, the elastic modulus of the hybrid composites has been reduced of only 24% on average. Thermo‐mechanical disassembly is used to recycle epoxy carbon fiber composite. Hybrid laminates are obtained by placing polyamide film between recycled plies. Pressure and heat are applied along the composite failure line for repairing. Hybrid composites repairing is carried out in comparison with neat materials. Repaired hybrid laminates have a higher elastic modulus than neat once. [ABSTRACT FROM AUTHOR]

Highlights This study evaluates the sliding wear behavior of hybrid composites made of epoxy reinforced with alternating layers of flax fiber mats and steel wire mesh. The aim is to enhance the wear resistance of flax fiber‐epoxy composites by incorporating steel wire mesh. Specifically, three composite types are produced by varying their stacking sequences using the simple hand layup technique. Dry sliding wear tests are performed on a pin‐on‐disc test rig under different conditions according to ASTM G99 standard. Taguchi analysis is performed using an L25 orthogonal array and it reveals that sliding velocity is the most critical factor, followed by normal load, in affecting the wear rate of the steel‐flax‐epoxy hybrid composite. Subsequently, a steady‐state wear analysis shows that sliding velocity and normal load increase the specific wear rate (SWR), while steel reinforcement decreases it. ANOVA results indicate that sliding velocity significantly impacts wear rates to the extent of 69.47% for flax‐epoxy composite and more than 70% for flax‐steel‐epoxy composites. Additionally, electron microscopy is used to study the worn surfaces of the composites to determine the wear mechanisms. Successful fabrication of flax‐steel wire mesh reinforced hybrid composites. Wear behavior of multi‐layer composites with different stacking sequence. Use of statistical technique for the prediction of wear rate. Wear mechanisms are identified using electron microscopy. [ABSTRACT FROM AUTHOR]

The main objective of this study is to investigate the effect of combining natural and synthetic fibers on the mechanical characteristics of hybrid and novel functionally graded hybrid composites by considering hemp as natural fiber and carbon and glass as synthetic fibers. Before manufacturing, the natural fibers were treated with sodium hydroxide (NaOH) solution to remove the impurities on the fiber surface. The fibers were reinforced in an epoxy‐based matrix using a hand‐layup technique. The volumetric fraction of the hybrid composites was 40% fibers and 60% matrix. Different types of composites, such as plain fiber reinforced polymer (FRP), sandwich hybrid (SH), alternative hybrid (AH), and functionally graded hybrid (FH), were manufactured from hybridizations of hemp/carbon and hemp/glass. In accordance with ASTM standards, the tensile, compression, flexural, short beam shear, water absorption, and wettability properties of composites were determined. FH composites with hemp fiber at the top surface had the highest improvement in tensile strength, stiffness and compressive strength compared with pure hemp FRP (HFRP) composites. Hemp SH composites had the highest improvement in flexural and short beam properties in both hybridizations compared with HFRP composites due to the stacking of synthetic fiber at the outer layers. Scanning electronic microscopic (SEM) studies identified the failure mechanism of the tensile failure specimens and also the effect of mercerization on fiber surfaces. In conclusion, this work identified the structural capacity of hybrid composites and emphasizes that FH and hemp SH composites can replace glass FRP composites in structural applications. Highlights: Treating hemp fiber with 2 g/L of NaOH for an hour had a better impact.Functionally graded composites had better in‐plane strength and stiffness.Composites made with synthetic fiber on the outer layers were good at bending.In structural applications, hemp/carbon hybrid composites can replace GFRP. [ABSTRACT FROM AUTHOR]

The study explores the microstructural design of hybrid Al2O3–Cu–Me composites formed by centrifugal slip casting into porous molds. Obtained composites are characterized by zones with different contents of metal phases. It was determined that there are two mechanisms driving thickening of slurries: capillary forces influencing smaller particles and centrifugal forces affecting larger particles. To enhance composite's cracking toughness, a gradient distribution of metallic phase with highest metal concentration near surface is essential. This is achieved by optimizing ceramic powder size, limiting processing time, and using gel centrifugal casting to eliminate undesired zones. Zone II's width is influenced by metallic phase proportion, mold rotation speed, and compaction rate, with heavier particles and greater metal content near outer surface. Zone III expands with lower rotational speeds and lighter metallic particles. The mutual reactivity and solubility of selected metallic elements also play a crucial role in the final microstructure. The findings highlight the potential for precise control over composite microstructures through careful selection of metallic elements, powder sizes, and casting parameters, offering valuable insights for model research and simulations. [ABSTRACT FROM AUTHOR]

This study aims to investigate the physical and mechanical properties of epoxy composites reinforced with hybrid luffa waste and groundnut shell waste natural fibers and to evaluate the effect of different filler loadings of alumina on the mechanical behavior of the hybrid composites. The luffa fibers were made to undergo mercerization in 10% NaOH solution. All the treated fibers and the alumina fillers were characterized using X‐ray diffraction analysis (XRD). The study used three different filler loadings of alumina (Al2O3) (5%, 10%, and 15% by volume) and three different fractions of treated luffa‐waste groundnut shell hybrid fibers (10%, 30%, and 50% by volume). The composites were fabricated using the hand layup technique, and the prepared test specimens were subjected to mechanical and physical properties testing as per ASTM standards. The experimental findings indicated that the inclusion of Al2O3 filler improved the physical and mechanical characteristics of the natural fiber‐reinforced hybrid composites. The results showed that the composites with 30 vol. % fibers (1:1 luffa fiber: groundnut shell fiber) and 10 vol. % Al2O3 content showed enhanced tensile, flexural, shear, and impact strength and hardness. Besides, a good synergy between the alumina fillers, natural fibers, and the polymer matrix was observed in the surface morphology of the composite specimen. The developed composites can be used in low and medium‐load‐bearing structural and non‐structural applications. Highlights: Development of hybrid polymer composites with luffa and novel groundnut shell fibersHybridization of alumina ceramic particles with natural fiber hybrid compositesAssessment of physical and mechanical properties of the polymer composites [ABSTRACT FROM AUTHOR]

This work aims to demonstrate the effect of ZrO 2 and MgO inclusion into the Poly(methyl methacrylate) (PMMA). To fabricate novel hybrid composites via heat cure method, various composites (PZM2, PZM4 and PZM6) were synthesized in the system [(95-x) PMMA + 5 ZrO 2 + x MgO] (x = 2, 4, and 6) respectively. Density of the prepared composites were determined and varying between 1.035–1.152 g/cm3. X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) followed by EDAX and mechanical testing were performed to evaluate the fabricated composite properties. Moreover, to explore the structure of the fabricated composites the 13 C CP-MAS SSNMR and 1 H-13 C Phase-Modulated Lee Goldberg (PMLG) HETCOR Spectrum were recorded which clarify chemical shifting and motional dynamics of the composites. Mechanical tests were performed by UTM and the obtained parameters such as compressive strength, Young's modulus, fracture toughness, brittleness coefficient, flexural strength and flexural modulus are found to be in the range of 91–100 MPa, 0.48–0.51 GPa, 9.122–9.705 MPa.m1/2 , 0.66–0.815, 51.03–42.78 MPa and 499–663 MPa respectively. Some more mechanical parameters such as proportional limit, elastic limit, failure strength, modulus of resilience and modulus of toughness were also calculated. Furthermore, tribological properties were also determined and the coefficient of friction (COF) was decreased by 17.4 % and 38 % for composite PZM6 at 20 N and 40 N as compared to the composite PZM2 and the lowest wear volume of 1.55 mm3 was observed for PZM2, whereas the maximum volume loss of 5.64 mm3 is observed for composite PZM6. To check out the biocompatibility, cytotoxicity and genotoxicity of the fabricated composites the Trypan-blue assay was also performed for PZM2 and PZM6 composites. Dissection on the gut of larvae was also performed on the both composites followed by DAPI and DCFH-DA staining. Therefore, these synthesized samples can be used for the fabrication of denture materials. [Display omitted] • Synthesis of ZrO 2 and MgO reinforced denture-based resin composites via heat cure method. • Density of the composites were determined and varying between 1.035-1.152 g/cm3. • The structure of the fabricated composites was studied using the 13 C CP-MAS SSNMR and 1 H-13 C Phase-Modulated Lee Goldberg (PMLG) HETCOR spectrum. • The PZM6 composite shows the maximum compressive strength, 100 MPa. • To check out the biocompatibility, cytotoxicity and genotoxicity, the Trypan-blue assay was performed. [ABSTRACT FROM AUTHOR]

The increasing reliance on electronic technologies has elevated the urgency of effective electromagnetic interference (EMI) shielding materials. This review explores the development and potential of magnetite-incorporated one-dimensional (1D) carbon nanostructure hybrids, focusing on their unique properties and synthesis methods. By combining magnetite's magnetic properties with the electrical conductivity and mechanical strength of carbon nanostructures such as carbon nanotubes (CNTs) and carbon fibers (CFs), these hybrids offer superior EMI shielding performance. Various synthesis techniques, including solvothermal synthesis, in situ growth, and electrostatic self-assembly, are discussed in detail, highlighting their impact on the structure and properties of the resulting composites. This review also addresses the challenges in achieving homogeneous dispersion of nanofillers and the environmental and economic considerations of large-scale production. The hybrid materials' multifunctionality, including enhanced mechanical strength, thermal stability, and environmental resistance, underscores their suitability for advanced applications in aerospace, electronics, and environmental protection. Future research directions focus on optimizing synthesis processes and exploring new hybrid configurations to further improve electromagnetic properties and practical applicability. [ABSTRACT FROM AUTHOR]

In recent years, natural fiber-reinforced hybrid composites have been utilized in many applications because of their lower cost, biodegradability, and low density. The aim of this research is to convert crab shell waste into an effective reinforcement in jute/carbon fiber hybrid composites. Various weight percentages of crab shell powder (0%, 1%, 3%, 5%, and 7%) were used to prepare crab shell powder hybrid composites. The performance of the crab shell powder hybrid composites was evaluated by preparing the specimens to conduct tensile, flexural, impact, and hardness tests as per ASTM standards. The results show that the inclusion of 5% crab shell powder displayed a better enhancement in the properties of the hybrid composite compared to other weight percentages. The tensile, flexural, and impact strengths of the 5% crab shell powder hybrid composite increased by 21%, 52%, and 50%, respectively. Also, the hardness of the hybrid composite was enhanced by 33%. Scanning electron microscopy (SEM) tests were conducted on the tensile-fractured specimen surfaces, and their morphology and structure confirmed the presence of a well-bonded interface between the fiber and matrix. Differential Scanning Calorimetry (DSC) and Thermogravimetry (TG) analysis have shown that the crystallization behavior and thermal stability of the composite were enhanced with the inclusion of crab shell powder. The presence of crab shell powder in the hybrid composite was identified using SEM with Energy-Dispersive X-ray Spectroscopy (EDS). [ABSTRACT FROM AUTHOR]

This paper proposes a technique for detecting impact-induced surface and subsurface fractures in Glass Fibre Reinforced Composites (GFRPs) and hybrid composite materials. Various categories of composite samples, namely Unidirectional GFRP, Bidirectional GFRP, Woven mat GFRP and Carbon-flax hybrid composites are fabricated by the hand-layup process, and cracks are induced in the samples by three-point flexural bending test using a Universal Testing Machine. Near-field microwave Non-Destructive Testing (NDT) is employed in detecting the above cracks by recording the S11 parameter from the microwave transceiver probe throughout the sample. For image rendering the resulting outputs are passed as a 2-dimensional array to the image-rendering algorithms, namely Iterative Curve-Based Interpolation (ICBI), Improved New Edge-Directed Interpolation (INEDI) and the Lanczos algorithm. The most suitable algorithm to identify the clear picture and size of crack is identified, and the effectiveness of Microwave NDT for these composites is analysed. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced composites (CFRP) are increasingly used in aviation and automotive industries. To enhance rigidity and fatigue resistance, aluminum (Al) and titanium (Ti) alloys are used together with CFRP materials. Drilling is a common method for manufacturing these hybrid composite stacks. This study examines the impact of process parameters, temperature, tool wear, thrust force, and torque on CFRP/Al/Ti hybrid composites during dry machining. Tests were conducted at various drilling speeds, feed rates, and stack orders using a solid carbide (WC) cutting tool. Results indicate that feed rate has a significant effect on the process outputs. The temperature remains low as the feed rate rises. The delamination factor is the highest in the Ti\CFRP\Al stack. In addition, delamination and temperature rise with increasing cutting speed. Finally, while the Al\CFRP\Ti stacking order performs poorly in terms of tool wear, it is measured more than 330 micrometers at the lowest feed rate. [ABSTRACT FROM AUTHOR]

Hybrid fiber-reinforced polymer (FRP) composites, combining different types of fibers within a polymeric matrix, have piqued the research community's interest due to their enhanced mechanical properties and functional performance. These materials offer optimized fiber usage, tailored failure responses, and potential for pseudoductile behavior. Furthermore, hybridization avoids catastrophic tensile failure despite the composites being composed entirely of brittle materials. Empirical evidence from previous research conducted on hybrid FRP composites for civil engineering applications suggests their potential as a promising asset to the field. This review paper collates extensive research and development work on hybrid FRP composites for civil engineering applications, providing a comprehensive summary since their inception. It covers areas including the development of reinforcing bars for reinforced concrete (RC) structures, externally bonded strengthening systems for RC structures, pultruded profiles for novel structures, and cables for long-span bridges. The paper begins with a concise overview of the influential developments that paved the way for hybrid FRP composites, followed by an in-depth discussion of their utilization in the construction sector. The paper concludes by extrapolating the potential future trajectory of hybrid FRP composites, providing insights into their future outlook. [ABSTRACT FROM AUTHOR]

This study focused on investigating the effects of micro-scale carbon fibers (CF) and nano-scale graphene nanoplatelets (GNP) on the morphological, rheological, mechanical, thermo-mechanical and thermal properties of polyamide 11/poly (lactic acid) (PA11/PLA) blend. A twin-screw extruder and an injection molding machine were utilized to produce the samples. The amount of GNPs was varied up to 5 wt% for a fixed CF fraction of 20 wt%, and the composites were characterized. SEM micrographs of hybrid composites revealed stronger interfacial interactions between the matrix and CF and improved dispersion of GNPs. The pseudo solid-like behavior transition and high modulus detected in the rheological study with the addition of GNP confirmed the strong matrix-filler interactions in hybrid composites. The synergistic effects of multi-scale fillers have been observed in mechanical and thermo-mechanical properties. In comparison to 20CF, hybrid composites' tensile strength and modulus increased by 8%–4.8% and 4.5%–17%, respectively, by adding 0.5–5 wt% GNP. Dynamic mechanical analysis revealed that the tan δ peak shifted to higher temperatures in low GNP containing hybrid composites, indicating an increase in Tg. Also, differential scanning calorimetry confirmed the Tg increment and synergistic effect of fillers on crystallization. The thermogravimetric analysis demonstrated that hybrid composites exhibited enhanced thermal stability. As a consequence, these hybrid composites offer an inventive viewpoint for environmentally friendly composites in the automobile industry thanks to their enhanced mechanical and thermal characteristics. [ABSTRACT FROM AUTHOR]

Natural fibre (NFR) reinforced functional polymer composites are quickly becoming an indispensable sustainable material in the transportation industry because of their lightweight, lower cost in manufacture, and adaptability to a wide variety of goods. However, the major difficulties of using these fibres are their existing poor dimensional stability and the extreme hydrophilicity. In assessing the mechanical properties (MP) of composites, the interfacial bonding (IB) happening between the NFR and the polymer matrix (PM) plays an incredibly significant role. When compared to NFR/synthetic fibre hybrid composites, hybrid composites (HC) made up of two separate NFR are less prevalent; yet, these hybrid composites also have the potential to be valuable materials in terms of environmental issues. A new dimension to the flexibility of composites reinforced with NFR is added by the cost-effective manufacture of hybrid composites utilising NFR. The purpose of this study is to offer an overview of the key findings that were presented on hybrid composites. The emphasis was focused on the factors that influence the performance of the natural fiber composites, diverse approaches to enhancing MP, physical, electrical, and thermal characteristics of the HC. HC study in polymer science gains interest for applications in construction and automotive industries. [ABSTRACT FROM AUTHOR]

Hybridization of natural fibers with ceramic materials for reinforcing composites allows the optimization of the properties of these materials. For this reason, the present study aims to investigate physical, mechanical, water absorption, swelling and thermal properties as well as morphological characteristics of a hybrid Paederia foetida fibers–alumina powder (PFs–Al2O3)‐reinforced epoxy composite. Epoxy resin served as the matrix, while PFs and Al2O3 were employed as reinforcement. Five types of composites were fabricated using the hot‐pressing technique. The corresponding ratios of PFs:Al2O3 volume fractions (%) considered here were 0:40 (SFA), 10:30 (SFB), 20:20 (SFC), 30:10 (SFD) and 40:0 (SFE). The results reveal that the density of the hybrid PFs–Al2O3 composites decreased for increasing volume fractions of PFs: from 2.173 g cm−3 of SFA to 1.042 g cm−3 of SFE. The highest values of tensile strength (i.e. 49.085 MPa), tensile elastic modulus (i.e. 1.431 GPa) and impact strength (24 kJ m−2) were obtained for the SFD composite material with 30% volume fraction of PFs and 10% volume fraction of Al2O3: this happened because interface bonds between PFs, Al2O3 and epoxy phases achieved their optimal configuration. Overall, mechanical properties of the hybrid PFs–Al2O3‐reinforced epoxy composites were superior to those of composites reinforced only by PF fibers or only by Al2O3. Water absorption and swellability reached their maximum values at the steady state occurring after tested samples remained immersed in water for 820 h. The SFE composite reinforced only by PFs presented the highest water absorption and swelling (i.e. 6.034% and 5.81%, respectively) while for all other hybrid composites (SFD, SFC and SFB) these two quantities remained below 5%. Density and volume fraction of voids of hybrid PFs–Al2O3‐reinforced composites were consistent with the corresponding properties of the composites reinforced only by Al2O3 or PFs. SFD was also the most thermally stable material. Scanning electron microscopy observations of fractured surfaces indicated that the microstructure of the PFs–Al2O3‐reinforced epoxy composites presents several voids, fiber pullouts and transverse fibers, which together optimize the mechanical response of the composite material. Remarkably, the SFD composite material was highly competitive with the most recently developed hybrid composites employing natural reinforcements. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

This article reports on development of an adaptive framework for predicting the erosion performance of polymer composites using certain statistical and machine learning (ML) models. For this, ramie‐epoxy composites reinforced with variations (0–30 wt%) of sponge iron slag (an iron industry waste) are considered. The composites are fabricated and then subjected to high temperature solid particle erosion wear trials following Taguchi's L27 orthogonal array. The effects of different control factors on the erosion rate in an interactive environment are appraised by analysis of variance (ANOVA) which reveals the filler content as the most significant factor contributing 66.21%, followed by impact velocity (22.86%) and impingement angle (2.28%). A regression model based on the input–output parameters obtained from experimentation is constructed for prediction of erosion rate. Further, four predictive models using different machine learning algorithms are also proposed to predict the erosion rate of the composites. The feasibility and performance of each ML model is assessed using appropriate performance metrics. Among all the models, the gradient boosting machine model is found to be the most reliable model exhibiting the highest prediction accuracy and least errors. Highlights: Development of novel class of composites reinforced with sponge iron slag.Database creation based on erosion wear experimentation on the composites.Data‐driven modeling for prediction of erosion rates using machine learning.Comparison of performance of different models and identifying the best one. [ABSTRACT FROM AUTHOR]

This research aims to improve the flame-retardant properties of wood–plastic composites with different recycled plastics. Acrylonitrile butadiene styrene (ABS) and polyvinyl chloride (PVC), flame-retardant materials, and recycled polypropylene (PP) were used as matrix in this research. Recycled ethylene propylene diene monomer (EPDM) with flame-retardant properties was also added to mix with rubberwood flour (RWF) to improve mechanical properties. The rubberwood flour, coupling agent (MAPP), and lubricant are fixed at 44.5%, 4%, and 1%, respectively, whereas recycled plastics and EPDM rubber contents are in the range of 30.5–50.5% and 0–20%, respectively. The composite materials were manufactured into panels using a twin-screw extruder and hot press machine. The experimental results were statistically analyzed by analysis of variance (two-way ANOVA) at a 95% confidence level. The highest values of the mechanical parameters of wood–plastic composites reinforced with recycled polypropylene (RWF44.5PP50.5) were 15.89 MPa, 42.26 MPa, 41.79 MPa, and 0.0202 J for tensile strength, flexural strength, compression strength, and impact strength, respectively. An increasing EPDM rubber content of wood–plastic composites provided better thermal properties. The thermogravimetric analysis and differential scanning calorimetry of hybrid composites with recycled ABS (RWF44.5ABS30.5EPDM20) obtained the highest value with thermal stability in the range of 255–284 °C. For the flammability properties, the hybrid composites with high EPDM rubber content were less flammable. Recycled PVC with content of RWF44.5PVC50.5 outperformed hybrid composites reinforced made from ABS and PP in terms of UL-94 and the limiting oxygen index with values of 25.73%. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical and tribological properties of Kevlar-based composites filled with varying weight percentages (5%, 10%, and 15%) of nano fillers, specifically nanographene oxide (GnO) and silicon dioxide (SiO2), intended for automotive applications. The composites were fabricated using the conventional hand layup method. To assess the mechanical performance, including tensile, flexural, interlaminar shear strength (ILSS), and hardness, tests were conducted to evaluate material strength. Tribological characteristics were examined through wear and frictional tests carried out under different temperature conditions, ranging from 50 °C to 250 °C, with a sliding speed of 0.261 m/s, loads varying from 156 N to 315 N, and a test duration of 120 min. Comparative results revealed that the composite containing 10 wt% SiO2 exhibited superior mechanical properties, with a tensile strength of 372.45 MPa, flexural strength of 339.92 MPa, ILSS of 56.38 MPa, and a hardness rating of 92 HRB. These improvements were attributed to the inherent hardness and effective dispersion of SiO2, enhancing matrix-fiber bonding. In comparison to nano GnO, the Kevlar fibers loaded with 10 wt% nano SiO2 demonstrated the highest capacity for reducing wear (0.554 × 10−3m3/Nm) and frictional coefficients (0.083). Because SiO2's stiff and strong structure offers a firm surface against the opposing material, it lowers friction and resists wear. The friction rate of the nano-fillers-loaded materials gradually increased with rising temperatures up to 200 °C and exhibited a significant increase from 200 to 250 °C. Conversely, Kevlar composites with 15 wt% SiO2 and 15 wt% GnO displayed higher wear rates, accompanied by pronounced fiber breakage and surface degradation, attributed to intense frictional forces generating thermal effects during sliding. Microstructural and structural characteristics of the hybrid composites were analyzed using high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), electron diffraction (ED), and X-ray diffraction (XRD). In summary, Kevlar composites with 10 wt% SiO2 filler demonstrated exceptional wear resistance, positioning them as promising candidates for automotive components prone to wear and friction, such as clutch systems, brakes, and engine parts. [ABSTRACT FROM AUTHOR]

In the current research investigation, jute and sisal intra‐hybrid woven fabric were specifically tailored to maintain jute and sisal in weft and warp directions, respectively. Jute sisal intra‐hybrid composites were prepared with four layers of intra‐hybrid woven fibers using a compression molding technique. Physical, mechanical (static and dynamic), and thermal stability behavior were investigated, and their structure–property relationship has been established. The obtained results showed that jute‐sisal cross‐interplay‐based hybrid composites recorded maximum tensile and flexural modulus values with minimum anisotropy. It can be concluded from the current experimental investigation that weft/warp orientation and stacking sequence play a significant role in defining the mechanical performance and anisotropic nature of woven fiber‐reinforced laminated composites. Also, the anisotropic properties can be minimized by investigating the effect of fiber orientation and hybridization of natural fibers‐based laminated composites. Highlights: Woven mats were tailored to orient different fibers in warp and weft directions.The influence of the fiber's orientation and stacking sequence was analyzed.Fiber orientation and hybridization have influenced mechanical performance.The alternative stacking sequence has shown the highest mechanical properties. [ABSTRACT FROM AUTHOR]