Fiber Loading Research Articles

Tribological behaviour of injection moulded composite fabricated using bio-fiber (flax fiber), bio-filler (halloysite nanotube), and biopolymer (polylactic acid)

Abstract This study investigates the wear and frictional behavior of the flax fiber (FF)/polylactic acid (PLA)-based green composite filled with bio-filler, namely, the halloysite nanotube (HNT). The HNT/FF-PLA composite was fabricated using injection molding, considering the fixed injection pressure (90 bars), speed (60 mm sec−1), and temperature (165 °C). The HNT/FF-PLA composite was engineered with an FF length of 5 mm and 20% fiber loading. This study examined the wear and frictional behavior of engineered HNT/FF-PLA composite by exploring the intrinsic influences of tribo parameters such as the sliding speed (1 to 3 m s−1) and the applied load (10 to 30 N). The HNT/FF-PLA composite was developed by varying the HNT filler as 1, 1.5, and 3 wt%. The wear responses, such as the coefficient of friction (COF) and specific wear rate (SWR) were considered as the performance parameters to be optimized through response surface methodology (RSM). The morphology of the HNT/FF-PLA composite worn test specimens was examined by scanning electron microscope (SEM). The primary purpose of this study is to optimize the wear and frictional behavior of the engineered HNT/FF-PLA composite, advancing its application as a sustainable material with superior tribological performance. The results highlight the influence of HNT filler, sliding speed, and load on the COF and SWR, where optimal parameters were identified using the RSM. All the process parameters were found to be significant for both COF and SWR. The minimum COF was found at a sliding speed of 1.007 mm s−1., load of 25.32 N, and filler wt% of 1.007. For SWR, the optimal parametric combination is 2.986 m s−1., 29.45 N, and 1.66 wt%.

Mechanical and Thermal Performances of Banana Fiber–Reinforced Gypsum Composites

This study investigates the use of alkali‐treated banana fibers at different weight percentages (0%, 4%, 6%, 8%, 16%, and 24%) as natural reinforcement in gypsum, aiming to assess their effects on the physical, mechanical, thermal, and morphological characteristics, as well as functional groups of composites. It is found that the density of banana fiber–reinforced gypsum composites (BFRGCs) decreases with increasing banana fiber content, reaching a minimum of 0.83 gm/cm3 at 24 wt.% fiber loading, while water absorption peaks at 98% for the same fiber loading due to the hydrophilic nature of banana fibers. Among the composites, the gypsum composite reinforced with 16 wt.% banana fiber exhibits superior mechanical characteristics, with a significantly higher tensile modulus (4.57 MPa) and flexural modulus (154.25 MPa), as well as tensile and flexural strengths of 0.81 MPa and 1.64 MPa, respectively, compared to the neat gypsum board. Further increasing fiber content to 24 wt.% results in lower tensile and flexural properties. However, adding a 24 wt.% fiber results in a substantial improvement (about 248%) in impact strength compared to the neat gypsum board. The hardness and thermal conductivity of BFRGCs reduce with increasing fiber, with the minimum hardness and thermal conductivity of 57.75 Shore A and 3.42 W/m2°C, respectively, at 24 wt.% fiber loading. Beyond 135°C, BFRGCs with 16 wt.% fiber and neat gypsum plaster lose around 15% and 19% of their mass. Scanning electron microscopy demonstrates that alkali treatment improves the fiber–gypsum interfacial bonding, whereas Fourier transform infrared spectroscopy confirms the existence of hydrogen bonds but shows minimal bond formation between the fibers and gypsum. The findings of this study provide insights into lightweight BFRGCs, highlighting their potential for applications in interior partition walls, false ceilings, decorative panels, and so on.

Pullout behavior of single and multiple arc-shaped fibers in SIFCON with various fiber spacings and loading rates

Pullout behavior of single and multiple arc-shaped fibers in SIFCON with various fiber spacings and loading rates

Study of Flexural Strength of Epoxy Composites Reinforced with Opuntia Ficus Indica Fibers

This study investigates the potential of Opuntia ficus indica (cactus) fiber as a reinforcing material in composite applications, particularly in combination with an epoxy matrix. Despite being a naturally abundant resource, cactus fiber remains underutilized in engineering. The research focuses on evaluating the flexural strength of cactus fiber-reinforced composites, with particular attention to how variations in fiber volume fraction influence bending strength. As a member of the Cactaceae family, which includes over 130 genera and nearly 1,500 species, cactus fiber offers a sustainable and eco-friendly alternative to conventional materials. With the growing demand for high-performance composite materials, this study underscores the potential of cactus fiber to enhance the mechanical properties and environmental sustainability of composite materials. Composites are prepared using cactus fibers of two lengths (8 mm and 10 mm) and varying weight fractions (20%, 25%, and 30%). The fibers are treated with a 5% Sodium Hydroxide (NaOH) solution by soaking it for 24 hours. The study investigates how fiber treatment, length, and loading affects the flexural strength or bending strength of cactus fibers. Results indicate that alkali-treated cactus fiber composites exhibit superior mechanical properties compared to untreated composites. Composites reinforced with 10 mm fibers show improved mechanical behavior over those reinforced with shorter fibers.

Effect of Extensive Solar Ultra-Violet Irradiation on the Durability of High-Density Polyethylene- and Polypropylene-Based Wood-Plastic Composites.

The natural and laboratory-accelerated weathering of wood-plastic composites (WPCs) based on high-density polyethylene (HDPE) and polypropylene (PP) plastics was investigated in this study. Injection molded samples of WPCs with different loadings of wood fiber ranging from 0 to 36 wt.% of wood were subjected to laboratory-accelerated weathering and natural weathering. The integrity of samples weathered to different extents was tested using a standard tensile test and surface hardness test to investigate the dependence of these properties on the duration of weathering exposure. Tensile data were used to identify the loading of wood fibers in either plastic matrix that afforded superior ultra-violet (UV) stability. Tensile measurements under uniaxial strain yielded average values of tensile strength (TS), low-extension modulus (E), and elongation at break (EB). Both natural weathering outdoors and accelerated weathering in the laboratory showed that the TS and EB decreased while the E increased with the duration of exposure for all samples tested. The change in the average TS of composites with the duration of exposure offers valuable insights. The correlation between the tensile and hardness data for the WPC samples was explored. After naturally weathering at two exposure sites, the hardness of the WPCs was found to decrease between 8% to 12.5%, depending on the composition and exposure location parameters. Furthermore, no marked difference in performance with increasing wood fiber beyond 18 wt.% was observed. WPCs can be a key parameter in environmental sustainability by being used in the building and packaging industries, which reduces carbon emissions and waste generation.

Optimization of strength properties of bamboo mesoparticles reinforced polyamide 6 using Box–Behnken approach

Bamboo mesoparticles were used as a viable alternative reinforcement in matrix polymers to produce eco-friendly products, and the alternative mesoparticles were used as reinforcement for cheaper processing methods and comparable mechanical properties as nanoparticle. The main factors that influence the mechanical behavior of natural composites are fiber size, fiber loading, and chemical treatment. This study optimized the blending parameters of bamboo mesoparticle/polyamide 6 composites through response surface methodology based on Box–Behnken design. The predicted strength values for these composites as a function of independent variables were obtained from the analysis of variance statistical approach. The analysis of the results showed that fiber size, fiber loading, and alkali concentration variables significantly in quadratic model terms. This model was used to determine the maximum strength, and it was closely in agreement with the experimental finding with the value of R2 = 0.9385. The optimum conditions for tensile strength were identified as fiber size 1 µm, NaOH of 2 wt.%, and fiber loading of 18 wt.%. The optimum conditions for flexural strength were identified as NaOH of 2 wt.%, particle loading of 13 wt.%, and particle size of 0.46 µm.

Assessment of fiber loading effects on mechanical properties and prediction of mechanical properties via artificial neural networks of hybrid jute /sheep wool epoxy composites

Abstract The primary purpose of this study is to realize the effect of fibre loading on mechanical properties like tensile, bending, impact, interlaminar shear strength and fracture toughness of hybrid composites made of alkaline treated jute and sheep wool hybrid fibres and epoxy. A series of composite laminates were prepared with varying fibre (30%, 40%, 50% and 60%) loadings using hand layup technique. The findings indicated that hybrid composite with equal amount of fiber and resin (JW50) showed a higher strength of 40 MPa against tensile load, maximum strength of 99 MPa against bending load, superior interlaminar shear strength (ILSS) of 3.09 MPa, and a maximum fracture toughness of 72 MPa.m1/2 compared to other fibre loadings. In terms of impact test, JW50 displayed the highest impact strength of 85.98 J/m, underscoring its exceptional capacity to absorb energy compared to other composites. The mechanical strengths of these composites were also predicted using an Artificial Neural Network (ANN) model, which generated accuracy of 87.46% for tensile strength, 86.31% for flexural strength, and 83.52% for impact strength. The absolute percentage errors were found to be 12.53%, 13.68%, and 16.47%, respectively, demonstrating the model’s reliability in estimating composite properties based on fibre content and composition. SEM images of fractured samples under tensile load reveal that higher resin content reduces fibre-matrix bonding, while a balanced fibre-to-resin ratio improves load transfer, but too much fibre leads to debonding due to inadequate resin justifying the experimental results.

Optimization of Abrasive Wear Parameters and Thermo-Mechanical Properties of Bauhinia Vahlii and Grewia Optiva Fiber Reinforced Hybrid Polymer Composites

Natural fiber-reinforced polymer composite offers competitive solutions for lightweight applications but faces significant abrasive wear challenges in many industrial and automobile applications. The current study aims to conduct mechanical, physical, and dynamic mechanical analyses, as well as three body abrasion examinations, on grewia-optiva (GO) and bauhinia-vahlii (BV) natural fiber-reinforced epoxy-based hybrid polymer composites containing marble dust as filler. Initially, the woven mat was knitted with an equal amount of grewia-optiva and bauhinia-vahlii natural fibers. Three weight percentages of the woven mat i.e. 10, 20, and 30wt.% were used as reinforcement, and industrial waste marble dust with a fixed amount of 5wt.% was also used as a filler material. GO, and BV fiber mats were chemically treated with 10wt—% NaOH for the cleaning and surface modification of fibers before their use as reinforcement. The fabricated composites' physical and mechanical characteristics, i.e., density, water absorption, hardness, impact, flexural, and tensile strength were examined experimentally. The value of the damping factor (tan δ), storage modulus (Eʹ), and loss modulus (Eʹʹ) of the developed composites were analyzed by a dynamic mechanical analyzer (DMA). The fabricated composites' three-body abrasive wear characteristics were also examined with varying parameters i.e. A: fiber loading, B: sliding distance, and C: normal load. The results show that increasing the fiber loading and using a constant amount of discarded marble dust improves all mechanical characteristics. The tensile strength, flexural strength, impact strength, and hardness improves by 15.99%, 26.30%, 24.40%, and 30.39% respectively for 10wt.% to 30wt.% fiber loading. The composites exhibit significant improvements in damping properties with fiber loading. Moreover, parameters i.e. normal load, speed, and fiber loading have contributed to abrasive wear of composites at 29.70%, 24.81%, and 19.07% respectively. This study will aid in the analysis of the morphological, mechanical, and thermo-mechanical properties of a new class of composite material that might be used for producing natural polymeric roofing systems, boats, and floors, as well as for the automobile industry.

Impact of fiber geometry, temperature, loading rate, and concrete mix on the pull-out resistance of iron-based shape memory alloy (Fe-SMA): Experimental investigation

An experimental campaign was conducted to determine the pull-out resistance of iron-based shape memory alloy (Fe-SMA) fibers embedded in high-performance fiber-reinforced concrete (HPFRC). Seventy-two specimens were examined using different thermal heating temperatures, loading rates, fiber end shapes, and concrete mixtures. The results indicated that end-hooked fibers had double the pull-out resistance of straight fibers. Increasing the temperature greatly reduced pull-out resistance in end-hooked fibers but had minimal impact on straight fibers. Concrete mixtures with higher compressive and flexural strengths exhibited greater pull-out resistance. Finally, the loading rate had a negligible effect; a tenfold increase induced merely a slight rise in pull-out resistance.

Effect of Fiber Loading on Green Composites of Recycled HDPE Reinforced with Banana Short Fiber: Physical, Mechanical and Morphological Properties.

Currently, research on composite materials derived from natural fibers and agro-industrial waste has generated industrial proposals for producing useful materials with sufficient mechanical strength for applications involving the reuse of waste for secondary purposes. The objective of this study was to determine the influence of fiber content on the final tensile strength of the composite material, serving as a reference for the manufacture of plates. To achieve this, high-density polyethylene (HDPE) composites reinforced with short banana fibers were prepared using a blade mill and hot compression molding techniques. Two levels of short banana fiber content-10% and 20% by weight-were used, along with two types of HDPE: virgin and recycled. We evaluated the effect of adding short banana fibers on the mechanical properties of the composite, specifically tensile strength, according to the ASTM D638 standard for polymeric materials. These results were correlated with the structural properties obtained through morphological, chemical, and thermal characterization of the developed materials. The mechanical evaluation results showed that the tensile strength and elastic modulus depend on the short banana fiber content and the type of high-density polyethylene. Thermogravimetric analysis revealed that the composites decompose faster than the pure polymers (virgin and recycled HDPE). Based on these findings, the composite material prepared under optimal conditions is recommended for use in walls or construction boards where high tensile strength is not critical, due to the decreased mechanical properties resulting from the incorporation of agro-industrial waste.

Modeling Electrical Conductivity of Injection-Molded Polymer Composite Bipolar Plates

Bipolar plates can be responsible for up to 40% of the total stack cost and 80% of the weight of a polymer electrolyte membrane fuel cell [1]. To reduce these cost and weight limitations, this work explores injection molding of polymer composites. Injection molding is well-suited for mass production and polymeric materials can significantly reduce the weight of traditional metallic bipolar plates. While polymers lack electrical conductivity, fillers can be added to fabricate conductive polymer composites. The main objective of this research is to model and injection mold polymer composites that will meet the United States Department of Energy technical target for bipolar plate electrical conductivity (> 100 S/cm).A fiber contact model was developed to predict electrical conductivity based upon direction in the material, fiber alignment, fiber length and diameter, fiber concentration, and fiber conductivity [2]. Fiber alignment was measured experimentally by imaging cross sections of injection-molded nylon/carbon fiber composites. Imaging was performed on samples with different weight percentages of carbon fiber and from different mold designs to compare how fiber angles change based on mold geometry. To reduce the significant time required to measure fiber angles experimentally, computer recognition and processing of fiber alignment was developed. Nylon composites were injection molded with carbon fiber loadings ranging from 5 to 40 wt%. Modeling predictions show good correlation within 20% of experimental conductivity measurements. Samples with at least 20 wt% carbon fiber exceeded the US DOE technical target for bipolar plate conductivity, reaching 250 S/cm. In addition to modeling electrical conductivity, the Halpin-Tsai equations are used to model the elastic modulus and ultimate strain of the polymer composite. Tensile testing showed that the modulus of elasticity increases with carbon fiber loadings up to 30 wt%, reaching 7.3 GPa. At loadings above 30 wt%, the higher filler content can create voids which decrease the modulus of elasticity. De Las Heras, A.; Vivas, F. J.; Segura, F.; Andujar, J. M., From the cell to the stack. A chronological walk through the techniques to manufacture the PEFCs core. Renewable & Sustainable Energy Reviews 2018, 96, 29-45.Weber, M.; Kamal, M. R., Estimation of the volume resistivity of electrically conductive composites. Polymer Composites 1997, 18 (6), 711-725. Figure 1

Mechanical characterization of natural fiber composites prepared with untreated and treated ficus religiosa root fibers

Surface modification techniques are used to modify the surface of the natural fibers in order to improve the surface characteristics; in turn other relevant significant properties of the fiber and its composites. In the present work, epoxy composites have been prepared with the untreated and treated F. religiosa root fiber samples at 5, 10, 15, 20, and 25 wt.% fiber loading. Mechanical properties such as tensile, flexural and impact strength of the prepared composite specimens have been tested as per the ASTM standards. From the results, it has been identified that the strength of the proposed composites increases with the increase in fiber loading, and the composites made up of 20 wt.% of the NaOH solution treated fiber sample exhibits better properties under mechanical characterization study. Alkalization filled the holes, cracks, and pores on the outer layer of fibers and significantly improved the surface roughness, which was reflected in the improvement of the proposed composites.

Synthesis, characterization and mechanical properties evaluation of muntingia calabura fibre reinforced epoxy composites: Fibre treatment comparison with NaOH and KOH

Numerous studies demonstrate that the alteration in the fibre surface caused by the alkali treatment enhances the mechanical capabilities. Muntingia calabura is the novel fibre was used in the present study. The present work illustrates the mechanical and characterization of NaOH and KOH treated muntingia calabura fibre reinforced epoxy composites. Muntingia calabura fibre is extracted from the bark of muntingia calabura plant. The collected fibres are treated with 10% alkali solution and then fibre–epoxy composites are fabricated with different fibre loadings, evaluated the mechanical properties of the Muntingia calabura fibre–epoxy composites. The interfacial bonding between the Muntingia calabura fibre and epoxy (LY-5052) observed with the morphological study. Using thermo gravimetric and infrared spectroscopy, the degradation behaviour and thermal stability of the Muntingia calabura fibre composites and the functional chemicals included in them are investigated respectively. The composites exhibit maximum tensile and flexural strengths of 84 MPa and 185 MPa, respectively, at 20 weight percent of the fibre content treated with NaOH. At 15 weight percent of the fibre content treated with NaOH, the composites have a maximum impact strength of 19.5 J/m2. It was found that the thermal stability of fibre composites treated with KOH and NaOH ranged from 250 to 400 degrees Celsius.

Investigation of Mechanical Properties of Short Sisal Fiber Reinforced Phenol Formaldehyde and Vinyl Ester Composites

Composite materials are replacing standard Engineering metals and alloys for many applications. Here in this work, Sisal fiber is used as reinforcement. Since it is abundantly available in nature and majority of it is getting wasted without being used as reinforcement in engineering applications. Short Sisal fiber reinforced Phenol Formaldehyde and Vinyl Ester resin composites are prepared with varied fiber lengths (5 mm and 10 mm) and for varied weight fraction (20%, 25% and 30%) of the fibers. The short Sisal fibers are treated with 5% of Sodium Hydroxide (NaOH) solution. In the present work, the effect of the fiber treatment, fiber length and fiber loading on the mechanical properties are investigated. The results show that the Alkali Treated Sisal fiber reinforced composites have better mechanical properties than untreated composites. The 10 mm fiber length reinforced composite shown improved mechanical properties than 5 mm fiber length reinforced composite. Increase in mechanical properties is seen when the fiber content in the composite is increased from 20% to 25% and 25% to 30%. The 30% weight of the Sisal fiber reinforced composite has shown higher values of mechanical properties.

Investigating the effect of polypropylene fibres and curing parameters on the workability and mechanical properties of concrete

Polypropylene fibers possess certain characteristics that make them an ideal counterpart to attain explicit advantages when used for building works, more specifically, when added to concrete. In this investigation, polypropylene fibers were added by weight of cement (0.25%, 0.5%, and 0.75%) in M20 grade of concrete and their impact on workability, compressive strength, and flexural strength were assessed and analyzed. The slump test revealed that as the polypropylene fiber loading in the concrete mix was increased, the workability of the mixture continued to decrease; the workability decreased by 11.11%, 19.44%, and 45.83% upon the addition of 0.25 %, 0.5%, and 0.75% fibers respectively in the concrete. The compressive strength, as well as the flexural strength of the concrete, increased monotonously with an increase in the curing time and fiber loading. For instance, in the case of acidic water curing, the compressive strength enhanced from 19.08 MPa to 22.85 MPa upon increasing the fiber content from 0.25% to 0.75%. Adding 0.25% polypropylene fiber resulted in an increase in the flexural strength of conventional concrete mix by 15.78% and 10.29% when cured in normal water for 28 days and 56 days, respectively. Both the compressive and flexural strength of the samples cured in normal water was found to be higher than the samples cured in acidic water and it was observed that the fibre-reinforced concretes were more resistant to acids than the normal unreinforced concrete.

Facile fabrication of 3D-printed cellulosic fiber/polylactic acid composites as low-cost and sustainable acoustic panels

This work presents a green, cost-effective and eco-friendly strategy to reduce noise pollution by developing biopolymer-based 3D-printed acoustic panels. We successfully fabricated two series of composites by varying the weight percentage (wt%) of cellulose fibers of water hyacinth (WH) and pineapple leaf (PAL), with polylactic acid (PLA) as the matrix via the heat-press method. All samples were characterized using Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Physico-mechanical properties, including hardness, tensile, and impact strength, were improved with increasing fiber loading. Filaments of 1 wt% water hyacinth fibers (WHFs) in PLA (1 WHF/PLA) and 1 wt% pineapple leaf fibers (PALFs) in PLA (1 PALF/PLA) were prepared and tested for 3D printability. The sound absorption coefficients (α) of the 3D-printed panels were investigated from 500 to 5000 Hz sound frequency range. The 3D-printed 1 WHF/PLA and 1 PALF/PLA acoustic panels achieve a maximum α (α-max) of 0.55 and 0.83 at 5000 and 4000 Hz, respectively, featuring the first work to report α-max > 0.5 at low fiber loadings in the high-frequency sound range. The tensile strength of the 3D-printed versions is significantly higher than non-3D-printed counterparts and commercial acoustic absorbers. Our data suggest the prepared 3D-printed panels are excellent candidates for acoustic applications at high-frequency noises. This study exhibits a facile, environmentally benign and sustainable approach to construct highly efficient and mechanically robust biopolymer-based 3D-printed sound-proof panels, which have promising potential as green engineering materials. Interestingly, this research also proposes a mitigation technology for the freshwater invader, Eichhornia crassipes (water hyacinths).

Effect of coir fiber loading on the mechanical, thermal, and physical properties of natural composites in applications of packaging

An increasing number of environmental regulations have shifted the spotlight toward the creation of ecological composite materials. This study examines, the effect of loading fiber and sodium hydroxide (NaOH) surface treatment on the water absorption, mechanical, physical, thermal, and morphological characteristics of coir fibers (CF) reinforced in a Kondagogu gum (KGG) matrix. The mechanical properties enhanced with the 10 wt% of CF composites, achieving tensile, flexural, and impact values of 2.30 MPa, 2.36 MPa, and 715.74 J/m2, respectively. Furthermore, coir fibers were treated with NaOH subsequent increases in the tensile, flexural, and impact properties with 6.08%, 78.38%, and 15.13%, respectively. The scanning electron microscopic (SEM) images, Fourier transform infrared (FTIR) spectrum, and water absorption of the composites were observed to ensure their suitability in packaging applications. With their advantageous hydrophilic properties, reduced density, and ability to remain thermally stable up to 255 °C, the treated NaOH CF/KGG composite is an appropriate fit for the interiors of the automobile sector.

Acoustic Emission based determination of delamination initiation in GFRP laminates

Acoustic Emission (AE) has the potential to identify delamination initiation in quasi-static Mode I fracture tests on glass fiber-reinforced polymer-matrix (GFRP) laminates. It had been shown that a combined AE activity and intensity criterion yields critical Mode I delamination resistance values GIC for an AS4/PEEK carbon fiber thermoplastic composite that are comparable to those from data analysis according to ASTM D5528. However, the AE historic index also allows for detection of delamination initiation under Mode I and Mode II loading of carbon fiber reinforced thermoplastics and thermosets. In the present study, these AE criteria for initiation under Mode I, Mode II and Mixed Mode I/II loading of GFRP epoxy laminates are compared with AE signal energy as additional initiation criterion. Initiation under Mode II and Mixed Mode I/II at a ratio of 4:3 was determined with two different set ups for each Mode. For some test configurations noise signals make unambiguous initiation detection difficult. Determination by means of AE energy or AE activity and intensity yields more conservative GC values compared with the AE historic index or criteria defined in the standards, however, with similar repeatability.

Effect of fiber loading on the mechanical, morphological, and dynamic mechanical characteristics of Calamus tenuis fiber reinforced epoxy composites

AbstractThis research delves into incorporating Calamus tenuis fibers as reinforcing material in polymer composites, conducting a thorough analysis of their viscoelastic, mechanical, and morphological attributes. Employing the hand layup method, Calamus tenuis fiber‐reinforced epoxy composites were crafted across a range of fiber loadings from 0 to 25 wt% with 5 wt% increments. Results highlight significant enhancements in mechanical attributes upon the incorporation of Calamus tenuis fibers into the matrix. Notably, the composite with 10 wt% Calamus tenuis fibers emerges as the top performer, showcasing unparalleled mechanical strength compared to neat epoxy. It achieves the highest tensile strength (21.08 ± 1.03 MPa) and tensile modulus (2.84 ± 0.09 GPa), along with the utmost flexural strength (63.31 ± 1.05 MPa) and flexural modulus (3.12 ± 0.16 GPa). Furthermore, it demonstrates remarkable impact strength (9.40 ± 0.40 J/cm2), emphasizing its resilience. Scanning electron microscopy (SEM) analysis confirms enhanced fiber‐matrix adhesion in the 10 wt% composite. Additionally, dynamic mechanical analysis (DMA) results reveal enhancements in storage and loss modulus, with the 10 wt% composites exhibiting the highest values. However, the damping factor decreases with the inclusion of Calamus tenuis fibers. Overall, a 10 wt% fiber loading is deemed ideal for enhancing the mechanical and dynamic properties of epoxy composites.Highlights Utilized Calamus tenuis fibers as reinforcing materials in epoxy composites. Investigated the mechanical, morphological, and viscoelastic properties. Calamus tenuis fibers boost epoxy composite mechanical traits significantly. SEM confirms improved fiber‐matrix adhesion in 10 wt% composite. DMA highlights elevated storage and loss modulus in 10 wt% composites.

The effects of fiber load and frictional work on fatigue behavior of water hydraulic artificial muscles in underwater environment

Water Hydraulic Artificial Muscles (WHAMs) exhibit characteristics of high pressure and substantial load capacity. In previous work, the fatigue life of WHAMs under elastic load has been investigated, and experimental results have indicated that the fatigue life is related to both fiber load and frictional work. To individually investigate the impact of fiber load and frictional work on the fatigue life of WHAMs, an experimental scheme was designed to test the fatigue life under different levels of fiber load and frictional work. Meanwhile, the working pressure and contraction range were determined for various working conditions, in order to assess their effects on the fatigue life of WHAMs. The W-test confirms that the fatigue life of WHAMs under each working condition follows a normal distribution. Based on the experimental results, the influence of fiber load and frictional work on fatigue life was analyzed. And the experimental results indicate that the impact of fiber load on the fatigue life of WHAMs is approximately three times greater than that of frictional work. Furthermore, substituting aramid 1414 fiber with aramid 3 fiber in the fiber sleeve led to a substantial increase in fatigue life, elevating the average fatigue life to more than 4 times. Based on the power-law model, a fatigue model of WHAM is established with fiber load and frictional work as factors. The relative error between the fatigue model and experimental results in previously published work demonstrates that the new fatigue model can accurately predict the fatigue life of WHAMs.