Hasil untuk "Mechanical industries"

R. Roy, D. Agrawal, Jiping Cheng et al.

P. Thomas, Tuerxun Duolikun, Nelson Pynadathu Rumjit et al.

Cellulose constitutes most of a plant's cell wall, and it is the most abundant renewable polymer source on our planet. Given the hierarchical structure of cellulose, nanocellulose has gained considerable attention as a nano-reinforcement for polymer matrices in various industries (medical and healthcare, oil and gas, packaging, paper and board, composites, printed and flexible electronics, textiles, filtration, rheology modifiers, 3D printing, aerogels and coating films). Herein, nanocellulose is considered as a sustainable nanomaterial due to its substantial strength, low density, excellent mechanical performance and biocompatibility. Indeed, nanocellulose exists in several forms, including bacterial cellulose, nanocrystalline cellulose and nanofibrillated cellulose, which results in biodegradable and environmentally friendly bionanocomposites with remarkably improved material properties. This paper reviews the recent advances in production, physicochemical properties, and structural characterization of nanocelluloses. It also summarises recent developments in several multifunctional applications of nanocellulose with an emphasis on bionanocomposite properties. Besides, various challenges associated with commercialisation and economic aspects of nanocellulose for current and future markets are also discussed inclusively.

S. Baptista-Silva, S. Borges, O. Ramos et al.

ABSTRACT Essential oils are products obtained from plants, by steam distillation, mechanical processes of citrus fruit epicarp, or dry distillation after separation of the aqueous phase by physical processes. They are usually composed of secondary metabolites of aromatic plants with oxygenated structures such as alcohols, ketones, aldehydes, and esters, presenting therapeutic properties such as antibacterial, antifungal and antioxidant activities. Essential oils are used in the pharmaceutical, food, and fragrance industries. The increasing use of plants by the pharmaceutical industry makes the study of essential oils crucial to design new bioactive delivery systems. This paper presents aliterature review that summarizes the best advanced data regarding the use of essential oils and their volatile constituents for biomedical applications with focuses on innovative pharmaceutical formulations. Nonetheless, it seems clear that more clinical evaluations are required until essential oils can be considered as possible applications in pharmacy or as adjuvants to current medications.

Tekalign Aregu Tikish, Yared Worku, Nithyadharseni Palaniyandy et al.

The growing demand for green energy has made energy storage crucial in energy generation systems. Supercapacitors (SCs) are gaining popularity in energy storage due to their high-power density and long cycle life. Bimetallic cobalt oxides (MCo2O4) are promising electrode materials due to their enhanced electrochemical performance and synergistic effects. This review provides a unique and exclusive focus on the recent 5-year progress (2020–2025) in MCo2O4 materials for SC applications. It provides a detailed analysis of various synthesis processes, the relationship between crystal structure (particularly the stable spinel structure) and electrochemical activity, the inherent battery-like charge storage mechanism of cobalt oxides, and a comparative performance evaluation. It also analyzes the electrolyte in Bimetallic Metal Oxides and their composites. The review highlights the strategic inclusion of a secondary metal (M = Ni, Cu, Fe, Mn, Zn) into cobalt oxide, which enhances key metrics, including specific capacitance, rate capability, and cyclic stability. Furthermore, this review demonstrated the strategies for improving overall SC performance through composite formation with conductive additives (carbon materials, metal oxides, conducting polymers, and MOFs). Lastly, the review concludes by summarizing the advanced and outlining crucial future research pathways to guide the development of superior bimetallic cobalt oxide-based SCs.

Ruijie Gu, Haotian Ye, Hao Xing et al.

The ball mill is a critical size reduction equipment in industries such as mining and metallurgy. However, the sustainable reliability modeling of the entire system is challenging due to its complex service conditions. This paper presents a systematic framework for the reliability analysis of ball mills based on Stress–Strength Interference Theory (SSIT). Based on a reliability block diagram (RBD), this study establishes a system-level reliability model for the ball mill. Within this framework, the cylinder model is developed using the energy conservation principle between impact energy and strain energy; the gear model comprehensively considers both contact and bending fatigue failure modes; and the bolt model is constructed through mechanical analysis in conjunction with Hooke’s law. In the case study, a laboratory-scale mill (Φ5.5 × 2.6 m shell, effective grinding chamber: 5.3 m inner diameter × 2.376 m length) operating at 14 RPM under dry grinding conditions is analyzed. The reliability of individual components and the entire system is computed using Monte Carlo simulation. The results indicate that the overall system reliability increases when one of the following three conditions is met: the surface hardness of the gear is higher and the tangential force is lower; the impact velocity on the cylinder is lower and the impacted area is larger; or the tensile force on the bolt is reduced.

Karthi Natesan, K. Kumaresan, S. Sathish et al.

Abstract Application of natural fibre reinforced polymer composites (NFPC) in transportation diligences has become inexorable due to light weight, superior properties, less cost of production and suitability to many products. But the main disadvantages of employing these fibers are their poor dimensional stability and high hydrophilic nature. Interfacial bonding between the fiber and matrix plays a vital role in deciding the mechanical characteristics of composites. Various chemical cures are applied for enhancing the fiber-matrix adhesion which ends up in better mechanical characteristics of the composites. The current aerospace and automotive industries are looking to change the conventional materials which are high density material to composite material for reducing the overall weight of the vehicle to increase its performance. This review paper provides a vast overview on natural fiber reinforced composites, various chemical treatments applied and applications of those composites.

K. Hasan, P. G. Horváth, T. Alpár

Composite materials reinforced with biofibers and nanomaterials are becoming considerably popular, especially for their light weight, strength, exceptional stiffness, flexural rigidity, damping property, longevity, corrosion, biodegradability, antibacterial, and fire-resistant properties. Beside the traditional thermoplastic and thermosetting polymers, nanoparticles are also receiving attention in terms of their potential to improve the functionality and mechanical performances of biocomposites. These remarkable characteristics have made nanobiocomposite materials convenient to apply in aerospace, mechanical, construction, automotive, marine, medical, packaging, and furniture industries, through providing environmental sustainability. Nanoparticles (TiO2, carbon nanotube, rGO, ZnO, and SiO2) are easily compatible with other ingredients (matrix polymer and biofibers) and can thus form nanobiocomposites. Nanobiocomposites are exhibiting a higher market volume with the expansion of new technology and green approaches for utilizing biofibers. The performances of nanobiocomposites depend on the manufacturing processes, types of biofibers used, and the matrix polymer (resin). An overview of different natural fibers (vegetable/plants), nanomaterials, biocomposites, nanobiocomposites, and manufacturing methods are discussed in the context of potential application in this review.

G. Jeevi, S. Nayak, M. Abdul Kader

Abstract Composites have been used extensively in various engineering applications including automotive, aerospace, and building industries. Hybrid composites made from two or more different reinforcements show enhanced mechanical properties required for advanced engineering applications. Several issues in composites were resolved during the last few years through the development of new materials, new methods and models for hybrid joints. Many components in automobile are joined together either by permanent or temporary fastener such as rivets, welding joint and adhesively bonded joints. Increasing use of bonded structures is envisaged for reducing fastener count and riveted joints and there by drastically reducing assembly cost. Adhesive bonding has been applied successfully in many technologies. In this paper, scientific work on adhesively bonded composites and hybrid composites are reviewed and discussed. Several parameters such as surface treatment, joint configuration, material properties, geometric parameters, failure modes, etc. that affect the performance of adhesive bonded joints are discussed. Environmental factors like pre-bond moisture and temperature, method of adhesive application are also cited in detail. A specific case of adhesive joints in hybrid bonded-bolted joints is elaborated. As new applications are expanding in the field of composites joining and adhesive joints, it is imperative to use information on multiple adhesives and their behaviour in different environmental conditions to develop improved adhesive joint structure in mechanical applications.

Z. Shen, Yuquan Ding, A. Gerlich

Abstract Friction stir spot welding (FSSW) is a variation of linear Friction Stir Welding (FSW), which was invented to compete with resistance spot welding (RSW) and riveting of lightweight alloys in the automobile, shipbuilding and aerospace industries. Recently, the application of FSSW has rapidly extended to a variety of metals and nonmetals. This article provides a comprehensive review of the recent progress on the process fundamentals, parameters optimization, microstructural evolution and mechanical properties, and relevant simulation and modeling of FSSW. The article also evaluates the energy generation, temperature distribution, plastic flow and joining mechanisms. The optimizations of tool design and welding parameters are obtained through experiments and modeling. Furthermore, a particular emphasis is given to microstructural characterization of the recovery, recrystallization and grain growth, and related annealing phenomena after in the welded alloys. The mechanisms of defect formation and liquidation cracking are discussed in detail. The mechanical properties, including hardness, static strength, fatigue performance and failure mechanisms and the relationship between mechanical properties and microstructures are also addressed along with residual stress and corrosion behavior.

O. Sigmund

Sanya Gupta, Sanjith M. Lakkol, Niranjan N. Prabhu et al.

The increasing demand for sustainable and environmentally friendly materials has driven significant research into natural fiber-reinforced composites. Among these, Carica papaya fibers have emerged as a promising candidate due to their renewable and biodegradable nature. This study investigates L12 matrix composites reinforced with Carica papaya fibers fabricated using the hand-layup method followed by compression molding. Several mechanical properties were experimentally analyzed, including Tensile strength (14.06 MPa), Flexural strength (45.02 MPa), Charpy impact strength (2.31 kJ/m2), Izod impact strength (29.81 kJ/m2), Interlaminar shear strength (ILSS) (4.614 MPa), and Vickers hardness (20.75). The morphological studies indicate good fiber-matrix bonding with minimal void content, contributing to enhanced mechanical stability. The results suggest that this composite is particularly suitable for lightweight structural applications, such as spectacle frames, aesthetic covers for appliances, and interior components in the automotive and airline industries (dashboards and door cards). The combination of moderate tensile strength, flexural strength, impact resistance, and lightweight characteristics positions it as an alternative material to synthetic composites in decorative and semi-structural applications. Additionally, the use of Carica Papaya fibers makes them an environmentally sustainable alternative to synthetic fibers, especially in applications where reducing waste and carbon footprints is critical.

Mamta Motiramani, Priyanshi Solanki, Vidhi Patel et al.

Green hydrogen is a cleaner source to replace fossil-based fuels and is critical in the global shift toward energy production to combat climate change. This review of embedding artificial intelligence (AI) and machine learning (ML) in the value chain of green hydrogen outlines the significant potential for full transformation. These include optimizing the utilization of renewable sources of energy, improving electrolysis process, hydrogen storage in the salt cavern that has better condition, and smarter systems in distribution side with inexpensive logistics. In this, it nullifies leak risks and safeguards the safety operations with detection using AI. Consequently, it positions the paper emphasizing AI-ML approaches demonstrating significant advancements in efficiency and sustainability in green hydrogen technology.

Giovanni De Gasperis, Sante Dino Facchini

Industrial monitoring systems, especially when deployed in Industry 4.0 environments, are experiencing a shift in paradigm from traditional rule-based architectures to data-driven approaches leveraging machine learning and artificial intelligence. This study presents a comparison between these two methodologies, analyzing their respective strengths, limitations, and application scenarios, and proposes a basic framework to evaluate their key properties. Rule-based systems offer high interpretability, deterministic behavior, and ease of implementation in stable environments, making them ideal for regulated industries and safety-critical applications. However, they face challenges with scalability, adaptability, and performance in complex or evolving contexts. Conversely, data-driven systems excel in detecting hidden anomalies, enabling predictive maintenance and dynamic adaptation to new conditions. Despite their high accuracy, these models face challenges related to data availability, explainability, and integration complexity. The paper suggests hybrid solutions as a possible promising direction, combining the transparency of rule-based logic with the analytical power of machine learning. Our hypothesis is that the future of industrial monitoring lies in intelligent, synergic systems that leverage both expert knowledge and data-driven insights. This dual approach enhances resilience, operational efficiency, and trust, paving the way for smarter and more flexible industrial environments.

Toni Seibold, Fabian Neumann, Falko Ueckerdt et al.

Greenhouse gas emissions from the steel, fertiliser and plastic industries can be mitigated by producing their precursors with green hydrogen. In Germany, green production may be economically unviable due to high energy costs. This study quantifies the 'renewables pull' of cheaper production abroad and high-lights trade-offs between cost savings and import dependence. Using a detailed European energy system model coupled to global supply curves for hydrogen and industry precursors (hot briquetted iron, ammonia and methanol), we assess five scenarios with increasing degrees of freedom with respect to imports. We find that precursor import is preferred over hydrogen import because there are significant savings in hydrogen infrastructure. Cost savings in the German industry sector from shifting precursor production to European partners compared to domestic production are at 4.1 bnEUR/a or 11.2 %. This strategy captures 47.7 % of the cost savings achievable by precursor import from non-European countries, which lowers industry costs by 8.6 bnEUR/a (23.3 %). Moving energy-intensive precursor production abroad allows Germany to save costs while still retaining a substantial share of subsequent value-creating industry. However, cost savings must be weighed against the risks of import dependence, which can be mitigated by sourcing exclusively from regional partners.

Dongyi Yi, Guibo Zhu, Chenglin Ding et al.

With the rapid advancement of Multimodal Large Language Models (MLLMs), numerous evaluation benchmarks have emerged. However, comprehensive assessments of their performance across diverse industrial applications remain limited. In this paper, we introduce MME-Industry, a novel benchmark designed specifically for evaluating MLLMs in industrial settings.The benchmark encompasses 21 distinct domain, comprising 1050 question-answer pairs with 50 questions per domain. To ensure data integrity and prevent potential leakage from public datasets, all question-answer pairs were manually crafted and validated by domain experts. Besides, the benchmark's complexity is effectively enhanced by incorporating non-OCR questions that can be answered directly, along with tasks requiring specialized domain knowledge. Moreover, we provide both Chinese and English versions of the benchmark, enabling comparative analysis of MLLMs' capabilities across these languages. Our findings contribute valuable insights into MLLMs' practical industrial applications and illuminate promising directions for future model optimization research.

Gauthier Roussilhe, Thibault Pirson, David Bol et al.

Growing attention is given to the environmental impacts of the digital sector, exacerbated by the increase of digital products and services in our globalized societies. The materiality of the digital sector is often presented through the environmental impacts of mining activities to point out that digitization does not mean dematerialization. Despite its importance, such a narrative is often restricted to a few minerals (e.g., cobalt, lithium) that have become the symbols of extractive industries. In this paper, we further explore the materiality of the digital sector with an approach based on the diversity of elements and their purity requirements in the semiconductor industry. Semiconductors are responsible for manufacturing the key building blocks of the digital sector, i.e., microchips. Given that the need for ultra-high purity materials is very specific to the semiconductor industry, a few companies around the world have been studied, revealing new critical actors in complex supply chains. This highlights strong dependencies towards other industrial sectors with mass production and the need for a deeper investigation of interactions with the chemical industry, complementary to the mining industry.

Awasthi Aditya Bachchan, Partha Pratim Das, V. Chaudhary

Abstract In this modern era, the world is deteriorating as there is an increase in pollution. It is not only giving rise to global warming but also deteriorate our water bodies most of which is contributed by the factories and industries. The synthetic fibers are also made in such type of industries. Synthetic fibers which are made from long-chain linking of hydrocarbons are made in such factories only which add to this pollution by fishing their hazardous waste into the water bodies. To cope up with this problem we should look for better alternatives and natural fibers are the best alternative to the toxic synthetic fibers. They are biodegradable, they do not pollute the environment in any way or the other, they have good tensile strength, they are durable, and they have high mechanical, thermal and tribological properties. The mechanical properties consist of tensile strength, impact strength, compressive strength e.t.c. and tribological properties show the wear and tear or the abrasive properties of the material. The natural fibers are long-lasting but when extracted by different medium and different methods show different characteristics in presence of moisture. Different natural fibers have different moisture absorption rates and different behaviour after moisture absorption. This present study is done to review the effect of moisture absorption on the properties of natural fiber reinforced polymer composites.

O. A. Jimoh, K. S. Ariffin, H. Hussin et al.

Rohit Chandel, N. Sharma, S. Bansal

S. Melly, Liwu Liu, Yanju Liu et al.

Dozens of hyperelastic models have been formulated and have been extremely handy in understanding the complex mechanical behavior of materials that exhibit hyperelastic behavior (characterized by large nonlinear elastic deformations that are completely recoverable) such as elastomers, polymers, and even biological tissues. These models are indispensable in the design of complex engineering components such as engine mounts and structural bearings in the automotive and aerospace industries and vibration isolators and shock absorbers in mechanical systems. Particularly, the problem of vibration control in mechanical system dynamics is extremely important and, therefore, knowledge of accurate hyperelastic models facilitates optimum designs and the development of three‐dimensional finite element system dynamics for studying the large and nonlinear deformation behavior. This review work intends to enhance the knowledge of 15 of the most commonly used hyperelastic models and consequently help design engineers and scientists make informed decisions on the right ones to use. For each of the models, expressions for the strain‐energy function and the Cauchy stress for both arbitrary loading assuming compressibility and each of the three loading modes (uniaxial tension, equibiaxial tension, and pure shear) assuming incompressibility are provided. Furthermore, the stress–strain or stress–stretch plots of the model's predictions in each of the loading modes are compared with that of the classical experimental data of Treloar and the coefficient of determination is utilized as a measure of the model's predictive ability. Lastly, a ranking scheme is proposed based on the model's ability to predict each of the loading modes with minimum deviations and the overall coefficient of determination.