Developing materials with superior acoustic and vibrational damping properties is essential for addressing challenges in industrial applications for noise and vibration control. This study focuses on the modeling and optimization of acoustic and vibrational performance in multi-walled carbon nanotube (MWCNT)-reinforced polymer composites by enhancing damping efficiency and optimizing MWCNT concentration, dispersion quality, and polymer matrix characteristics, significantly influencing the material’s dynamic behavior. A dynamic response model of the polymer nanocomposites was developed by coding in MATLAB environment followed by Teaching–Learning-Based Optimization (TLBO) algorithm to optimize the critical parameters. The optimization process effectively identified the ideal MWCNT content and dispersion to maximize damping performance while maintaining the structural integrity of the composite material. The results demonstrate a significant improvement in the noise and vibration attenuation capabilities of optimized MWCNT composites with coefficient of determination (R2 = 0.98), root mean square error (RMSE = 0.012), and mean absolute percentage error (MAPE = 1.831

Composite materials blend diverse materials to create a new one with unique properties. These materials are divided into two types: synthetic and natural. Synthetic composites, like glass fiber, are strong and durable but environmentally unfriendly due to their non-degradable nature and the high energy required for production. Conversely, natural composites are made from renewable plant fibers and are environmentally friendly, offering advantages such as degradability and lower production energy. The shift toward natural composites is driven by the global push for sustainability and reduced environmental impact. This study examines Pineapple Leaf Fiber (PALF) and banana fiber as sustainable alternatives to synthetic fibers. It explores their historical background, extraction methods, and applications, highlighting their environmental benefits, including sustainability and degradability. PALF is noted for its excellent mechanical strength and cost-effectiveness, making it ideal for the textile and paper industries, among others. Banana fibers, known for their flexibility and strength, are versatile in textile production, craftwork, and composite reinforcement. This research underlines the growing interest in these fibers for their eco-friendly properties, contributing to the development of sustainable materials science. It addresses the challenges in enhancing these composites’ performance and suggests future research directions. Adopting natural fiber composites is a significant step toward sustainable material engineering, emphasizing the need to move from synthetic to natural materials in various sectors.

Natural fiber-reinforced composites have become an important field of research due to their environment-friendly nature, low cost, lightweight, and excellent mechanical properties. In the current study, natural composites were fabricated by the hand layup technique to investigate the influence of pineapple leaf fiber (PALF) orientation on the mechanical properties and water absorption behaviors of epoxy composites. Pineapple leaf fibers, known for their natural fiber reinforcement capabilities, were incorporated into polymer matrices at various orientations (45°, 60°, 75°, and 90°) to evaluate their impact on the composite’s performance. Mechanical properties (tensile strength, flexural strength, impact energy, and micro-hardness) were assessed to understand how fiber alignment influences the overall structural integrity of the composite. Additionally, the water absorption characteristics of the fabricated composites were assessed by immersing specimens in water and measuring water uptake over time. Results revealed that fiber orientation plays a crucial role in enhancing mechanical strength and tribological properties, with composites reinforced with fibers aligned at 90° demonstrating efficient load transfer and reduced water absorption. Conversely, composites with fibers oriented at 45° showed relatively lower mechanical strength, higher water absorption, and lower tribological performance. These findings suggest that the optimization of fiber orientation in polymer composites can lead to enhanced performance and durability, making them suitable for an extensive range of eco-friendly and sustainable applications.

This study presents the development and classification of eco-friendly composite panels reinforced with spent coffee grounds (SCG) and banana stem fibers (BSF) for interior applications. Hybrid composites were fabricated using polylactic acid (PLA) as the matrix with a constant filler loading of 30 wt%, varying BSF:SCG ratios (70:30, 60:40, 50:50). Mechanical testing revealed that the 70:30 composite exhibited the highest tensile strength (42 MPa) and flexural strength (58 MPa), whereas the 50:50 composite showed superior impact strength due to the energy-dissipating nature of SCG. Thermal analysis demonstrated that the hybrid composites had a decomposition onset temperature of 320 degrees C, surpassing that of neat PLA, confirming enhanced thermal stability. Differential Scanning Calorimetry revealed minimal changes in glass transition temperature (similar to 60 degrees C), while crystallinity slightly decreased with increasing SCG content. Notably, the 60:40 composite achieved the highest noise reduction coefficient (NRC) of 0.61, making it suitable for acoustic paneling. Water absorption increased with SCG content, from 3.2% (70:30) to 5.0% (50:50), due to the hygroscopic nature of SCG. The results demonstrate that BSF-SCG reinforced PLA composites are structurally robust, thermally stable, acoustically efficient , biodegradable, offering a sustainable alternative to traditional MDF , gypsum-based panels. These composites align with green building initiatives and circular economy goals.

In this present investigation, the mechanical characterization and water absorption behaviors of chopped luffa cylindrica fiber and chopped basalt fiber epoxy hybrid composites are experimentally study. These composites were developed by using hand lay-up processes with constant weight percentage of fiber and matrix as 30:70. The mechanical behaviours like as tensile, flexural, impact strength, micro-hardness and water absorption properties were examined. The FE-SEM (field emission scanning electron microscopes) of sampled with the tensile fracture was also conducted. The finding revealed that the hybridization of luffa-basalt-epoxy composites significantly increase the tensile strength and modulus with compared to neat luffa and neat basalt fiber composites, respectively. Hybridization of luffa and basalt fiber composites raise flexural strength and modulus in a similar as tensile strength. If compared to neat basalt/epoxy composites, the moisture absorption of the luffa-basalt-epoxy composites could not be reduced by hybridization.

Nickel–titanium (NiTi) shape memory alloy has diverse applications, especially in areas such as the medical, aerospace, and aeronautical industries. Due to this alloy’s excellent fatigue strength, high mechanical properties even at higher temperatures, and tendency to corrosion resistance, NiTi alloy is considered difficult to machine. In the present scenario, electrochemical arc machining ECAM (hybrid of electric discharge erosion and electrochemical dissolution) is an evolving procedure for difficult to machine the materials due to constraints of existing processes. The present research aims to investigate the machinability of Ni 55.7 Ti alloy through electrochemical arc drilling using molybdenum electrode. Electrolyte concentration (ethanol with ethylene glycol and sodium chloride), supply voltage, and tool rotation are considered as the variable factors in order to evaluate the ECAM performance characteristics in drilling blind hole operation concerning overcut, tool wear rate, and materials removal rate. Consequently, response surface methodology is implemented for predictive modeling of various performance characteristics. Finally, multi-objective optimization through DFA has produced a set of optimal parameters to improve the productivity along with the accuracy, which is the prime requirement for the industrial applicability of the ECAM process. Results demonstrated that supply voltage is the influential key factor for improvement of machining rate. SEM photographs revealed the development of HAZ, white layer, melted droplet, craters, re-solidified material, ridge-rich surface, and voids as well as cavities around the end-boundary surfaces of a blind hole. Composition analysis through EDS indicated the oxygen content on the machined surface because electrolyte breakdown causes oxidation to take place at elevated temperatures across the machining zone. Moreover, carbide precipitation like TiC was found in the melting zone of the drilled hole which has the affinity to reduce the SMA properties in HAZ.

In the present scenario, electrochemical arc machining (ECAM) (hybrid of electric discharge erosion and electrochemical dissolution) is an evolving procedure for difficulty in machining the materials due to constraints of existing processes. This research aims to investigate the machinability of Ni[Formula: see text]Ti alloy through electrochemical arc drilling using molybdenum electrode. Electrolyte concentration (ethanol with ethylene glycol and sodium chloride), supply voltage, and tool rotation are considered as the variable factors to evaluate the ECAM performance characteristics in drilling blind hole operation concerning overcut (OC), tool wear rate (TWR) and materials removal rate (MRR). Consequently, response surface methodology is implemented for predictive modeling of various performance characteristics. Finally, multi-objective optimization through desirability function approach (DFA) has produced a set of optimal parameters to improve the productivity along with the accuracy, which is the prime requirement for the industrial applicability of the ECAM process. Results demonstrated that supply voltage is the influential key factor for improvement of machining rate. Scanning electron microscope (SEM) photographs revealed the development of heat affected zone (HAZ), white layer, melted droplet, craters, re-solidified material, ridge-rich surface and voids as well as cavities around the end-boundary surfaces of a blind hole. Composition analysis through energy dispersive spectroscopy (EDS) indicated the oxygen content on the machined surface because electrolyte breakdown causes oxidation to take place at elevated temperatures across the machining zone. Moreover, carbide precipitation like TiC was found in the melting zone of the drilled hole, as revealed by X-ray diffraction (XRD) analyses, which has the affinity to reduce the SMA properties in HAZ.

Natural fibre reinforced polymer composites have found a wide range of applications in the automobile industry, construction industry and toy industry, and so on. In this research work, bidirectional aloe vera fibre mats were used as reinforcement and epoxy as matrix materials. Hand Layup process was applied for fabrication of aloe vera fibre reinforced epoxy matrix composites which contain different fibre orientations such as 45 degrees, 60 degrees, 75 degrees, and 0 degrees/90 degrees. The goal of this research work is to obtain the influence of fibre orientation on mechanical and water absorption properties. The experimental investigations like tensile strength, flexural strength, impact strength, and the water absorption tests were performed. The surface morphology of the tensile failed test specimens were alsoanalysed using afield emission scanning electron microscope (FE-SEM). When compared to other fibre orientation composites, 0 degrees/90 degrees aloe vera fibre orientation has superior mechanical capabilities and 45 degrees fibre orientation obtained minimum mechanical properties, according to the results of the experiment. As compared to 45 degrees fibre orientation, 90 degrees fibre orientation obtained 283.81%, 168.41%, and 202.54% higher tensile, flexural, and impact strength, respectively.

Due to its superior properties such as light weight, biodegradable, low density, readily accessible, low cost, high specific strength etc., natural fibre-reinforced polymer composites have been a wide field of research over the last few years. The effect of the fibre content on the mechanical property and water absorption behaviour of luffa cylindrica fibre-reinforced epoxy composite is studied in this research paper. The surface morphology of tensile fracture specimens is also analysed using FESEM analysis. Four different types of composites were prepared by using hand layup technique with varying fibre content such as 4%, 8%, 12% and 16 wt%. The mechanical behaviours of composites have been analysed, such as tensile strength, flexural strength, impact strength and water absorption properties, respectively. The experimental result shows that the water absorption increases with increase in fibre weight percentage. Similarly mechanical properties increase up to 12% luffa fibre content in a composite. Maximum tensile, flexural and impact strength obtained 19 MPa, 50.2 MPa and 2.3 joule, respectively, in 12 wt% luffa fibre composites. But maximum water absorption was obtained as 10.2% in 16 wt% of luffa fibre composites.

Geo-reinforcement is one of the most important utilities whose primary function is to mechanically enhance the strength of soil specifically engineered for the construction of geo-structures. Utilizing polymer-based geosynthetic reinforcement for various applications in pavements has been successfully used for the past few decades. However, with the growing awareness towards the environment and climate change, there is a constant lookout for energy-efficient and sustainable reinforcing materials for road construction. Lignocellulosic fibres are sustainable and have the potential to replace synthetic reinforcing materials, especially for low-volume rural road construction (expected commercial vehicles less than 450 per day) wherein traditional ground improvement techniques are considered to be expensive. Extensive studies have focused on the enhancement of mechanical properties of subgrade by the inclusion of natural reinforcing materials based on laboratory and field studies without comprehensively understanding the problems associated with the durability and field compatibility in low-volume roads. Lack of clear understanding of these lignocellulosic fibres and the fibre-based geotextiles resulted in the reluctance in the material usage in most applications. An extensive review of the existing studies from the last 30 years was used to obtain a relationship between the physical, biochemical and mechanical characteristics of the lignocellulosic fibres to efficiently utilize them as reinforcing materials. Further, the various treatment techniques required to enhance the strength, stiffness, and durability of these fibres are critically examined. In addition to a complete understanding of the properties and treatment techniques for lignocellulosic fibres, the factors affecting the mechanical performance of coir (CGT) and jute (JGT) fibres-based geotextiles have been analyzed using regression techniques to efficiently utilize them as a reinforcing material in low-volume rural road construction. Finally, the increase in soil properties due to the presence of CGT and JGT is examined using extensive laboratory and field investigations/ case studies, thereby mitigating rutting, cracking, differential settlement, and other major failures in the flexible pavement. Based on this study, the scope for future research is also outlined.

The mechanical behaviors and tensile fracture surface morphology of basalt bidirectional mat fiber based epoxy composites were investigated in the present experimental work. Composites with varying fiber orientation angles such as 45°, 60° and 90° laminated using hand layup techniques. Mechanical behaviors like as tensile strength and tensile modulus, flexural strength and flexural modulus, impact strength (charpy & izod) as well as micro hardness behaviors investigated experimentally. The result showed that maximum mechanical properties obtained in 90° fiber orientation composite as compared to other developed composites.

Hydraulic components play a significant role in the mining and construction equipment. It is responsible for smooth change in the output speed, torque, and power of the machine. The hydrostatic drive powered by a constant speed electric motor is widely used in the propel system of the mining equipment. Regulation of the displacements of the pump and the hydro-motor of the drive facilitates the control of the straight running and steering of the machines. In the present scenario, better efficiency and ease of control are the critical aspects to be considered in the design and selection of the hydraulic pump and motor used in underground mining operations. The bent axis hydro-motor is one such equipment that is an electro-hydraulic component that can work in an adverse working environment. The present study deals with the performance analysis of fixed displacement bent axis hydro-motor at different operating parameters such as different temperatures, sizes, viscosity at different loads, and drive speed. For analysis, the hydraulic drive consists of a variable displacement pump rotated by a constant speed electric motor and a fixed displacement hydro-motor. The regulation of the pump displacement controls the speed of the drive. Manually controlled hydrostatic drive propels the said machine against variable load demands. The present work investigates the performances of the hydro-motor used in the mining and construction machine through detailed modeling and experimentations. The steady-state performances are analyzed in terms of slip, torque losses and efficiency of the hydro-motor. The study finds the design guideline to operate the hydrostatic drive using such motors in a reasonable efficiency zone. The model is validated for various operating conditions of the equipment by comparing the predicted results with the test results. The outcome of the present work will be expedient for the preliminary design and assortment of similar hydraulic component used in the mobile, mining equipment.

In this study, the mechanical behavior and water absorption behavior of borassus fruit fiber (BFF)/basalt fiber-reinforced epoxy hybrid composites are studied experimentally. The mechanical behaviors as a feature of fiber reinforcement demonstrate that the application of basalt fiber to the BFF/epoxy composites improves mechanical properties such as tensile modulus and strength, flexural modulus and strength, as well as impact resistance and microhardness. However, water absorption behavior cannot be reduced by hybridization as compared with neat basalt fiber-reinforced composites. The result indicates that hybridization of BFF/basalt fiber-reinforced composites improved tensile strength 30.70% and 7.20% and tensile modulus 9.60% and 5.43% as compared with neat BFF and neat basalt fiber composites, respectively. Similarly, flexural strength improved 71.80% and 34.91% and flexural modulus improved 50.43% and 13.04%, respectively, as compared with neat BFF and neat basalt fiber composites. Impact strength and microhardness are also significantly improved by hybridization of BFF/basalt fiber-reinforced composites. However, moisture absorption cannot be reduced by hybridization of the above composites as compared with basalt/epoxy composites.

The application of natural fibre composites has increased manifold due to their environment-friendliness and sustainable characteristics. In this study, short Borassus fruit fibre (natural fibre)-based composites were fabricated and the water absorption and mechanical (tensile, flexural and impact) behaviour of the developed composites were evaluated. Alkali treatment of Borassus fruit fibres was also carried out at different concentrations (4, 8 and 12%) of sodium hydroxide (NaOH) to investigate the influence of the concentration of sodium hydroxide on the water absorption and mechanical behaviour of the developed composites. The water absorption behaviour of the fabricated composites was tested under three distinct conditions - namely, Ganga water, distilled water and tap water. The surface morphology of the Borassus fibres showed that the sodium hydroxide treatment of the fibres resulted in surface modification of the fibres, which subsequently resulted in improved mechanical strength and less water uptake tendency by the developed short Borassus fibre-based composites.

Abstract The main objective of this experimental work was to evaluate the mechanical (tensile, flexural, impact, and microhardness) and water absorption behaviors of borassus/epoxy composites. The composites were fabricated by varying the weight percentages of borassus fruit fiber from 5 to 20 wt.-%. The surface morphology of the failed test specimens were also analyzed using FESEM. The composites reinforced with 15 wt.-% borassus fruit fiber were found to have superior mechanical properties when compared with other developed composites. The water absorption was higher for the composites having fiber weight percentage of 20.

The main objective of the current experimental work is to determine the mechanical properties of borassus fruit fiber (BFF)-based composites and compare the mechanical performance of composites fabricated with different chemically treated BFFs. The BFFs were treated with (a) sodium hydroxide (NaOH), (b) benzoyl chloride (C6H5COCl) and (c) acetyl chloride (CH3COCl), and the surface morphologies of the BFFs were compared with the assistance of scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy. The mechanical properties such as (a) tensile properties, (b) flexural properties, (c) hardness, (d) impact and (e) water absorption behavior of the treated and untreated BFF-based composites were evaluated. The experimental findings showed that the mechanical properties of the BFF-based composites were better than those of the neat epoxy chosen for investigation. The chemically treated BFF-based composites were found to have enhanced mechanical properties and reduced water absorption tendency compared with the untreated BFF-based composites. SEM examination showed that the acetylation-treated BFF-based composites had higher surface roughness and thus excellent mechanical properties and less water absorption tendency among all the chemically treated and untreated BFF-based composites.

Horsehair-based composites have been prepared by reinforcing polylactic acid (PLA) using hot compression molding. The weight fraction of horsehair fibre in composites has been varied from 0% to 30 wt.% to investigate the effect of fibre loading on the mechanical properties and moisture absorption performance of the developed composites. The mechanical properties, such as strength and modulus (tensile and flexural), impact energy, and moisture absorption behaviour of the fabricated composites, are experimentally evaluated. The experimental results recommend that the composites reinforced with 20 wt.% horsehair exhibit superior mechanical properties as compared to other developed composites. The tensile strength and modulus, flexural strength and modulus, Charpy and Izod impact energy of the composites reinforced with 20 wt.% horsehair are improved by 9.52, 28.74, 7, 5.63, 398.11 and 379.31% as compared to, one-on-one, neat PLA. The findings also reveal that the percentage of moisture absorption of the developed composites increases with an increase in the fibre content in the developed composites.

Effect of different stacking sequence of jute and flax fabrics on the tensile, water absorption and wear properties of hybrid composite laminate has been studied. The composites have been manufactured by hand lay-up technique. The stacking sequence configurations are set as JJJJJ (jute-jute-jute-jute-jute), JFJFJ (jute-flax-jute-flax-jute), JFFFJ (jute-flax-flax-flax-jute), FJJJF (flax-jute-jute-jute-flax) and FJFJF (flax-jute-flax-jute-flax). It is found that the specimen with FJFJF sequence has highest tensile strength (149.12 MPa), less water absorption and better wear resistance than that of the other sequences.

In the last few years natural fiber reinforced polymer composite materials have been developing very rapidly in the field of materials development, due to various advantages such as their biodegradability, low cost, light weight, high specific strength, easily machinability and eco friendly nature etc. In present work animals fibers (Hair) were used as the reinforcing material and polypropylene (PP) as the resin. Composites materials were fabricated by using compression moulding techniques. Content of horse hair (HH) was varied from 0, 10%, 20% and 30% respectively by fixing the fiber (hair) length. Experimental results show that mechanical properties such as tensile strength, flexural strength, impact strength increases 20% content of HH and after that a further increase in the content of HH, mechanical properties are negatively affected but water absorption continues to increases with the increase in the content of HH.