Lightweight Applications Research Articles

Numerical simulation of a novel high performance solid‐state dye‐sensitised solar cell based on N719 dye

AbstractAmong the emerging photovoltaic technologies, solid‐state dye‐sensitised solar cells (ssDSSCs) have attracted considerable interest due to their cost‐effective production, adjustable characteristics, and potential for lightweight and flexible applications. Nevertheless, achieving efficiencies comparable to established technologies, such as perovskite and silicon‐based solar devices, have proven challenging. Herein, the device structure, Pt/PEDOT: PSS/N719 dye/PC61BM/ITO is investigated theoretically using the solar cell capacitance simulator (SCAPS‐1D). Groundbreaking advancement is introduced in ssDSSC design, achieving remarkable theoretical power conversion efficiency of 20.73%, surpassing the performance reported in traditional dye‐based solar cell technologies. The model ssDSSC demonstrates an exceptional Fill factor of 86.64%, indicating efficient current collection; along with a modest short‐circuit current density (Jsc) of 22.38 mA/cm2 and an impressive open‐circuit voltage (Voc) of 1.0691 V, highlighting efficient light absorption and charge separation. Mott–Schottky capacitance analysis and parasitic resistances (series and shunt) have been thoroughly discussed. Despite the fact that only numerical simulation is involved, the proposed ssDSSCs structure gives insights into the fabrication of a highly efficient solar cell that can be injected into the production workflow in order to advance the photovoltaic technology of the solid‐state DSSC.

Isolation and characterization of banyan tree root filler for polymer composites in light-weight applications

The applicability of bio fillers as reinforcement with polymers is promoted by economic and ecological concerns. Nowadays, a large range of reinforcements are employed for this purpose, including cellulosic fillers and natural fibres owing to the favorable mechanical behavior, cheap price, negligible tool wear, low density, and eco-friendliness etc. The motive of this investigation is to explore the possibilities of utilizing plant sources as reinforcing filler in polymeric matrices. In this study particulate fillers were obtained from banyan tree’s aerial roots and were subjected to various characterization such as physiochemical evaluation, Fourier Transform Infrared Spectroscopy (FTIR), x-ray diffraction (XRD), thermal analysis (TGA), and Scanning Electron Microscopy (SEM). From the physiochemical analysis it was found that the banyan tree aerial root filler (BTAR) contained 40.13% of Cellulose, 15.22% of Hemicellulose, 15.31% of Lignin and 6.86% of Pectin. The density of the BTAR filler was found to be 0.27 gm cc−1 whereas the average particle size was 136.3 μm. The maximum inflection temperature referred to the maximum degradation of the BTAR filler was 295.7 °C. The SEM analysis exposed the rough surface of filler, with micro-structured strands and pores. The rough surface and the pores could help in better bond ability of the matrix and reinforcement when combined. Given the features of the examined BTAR filler, it is suggested as potential reinforcing filler for polymer composites to strengthen material properties for different light weight applications.

Multidisciplinary design optimisation of lattice-based battery housing for electric vehicles

Batteries with high energy densities become essential with the increased uptake of electric vehicles. Battery housing, a protective casing encapsulating the battery, must fulfil competing engineering requirements of high stiffness and effective thermal management whilst being lightweight. In this study, a graded lattice design framework is developed based on topology optimisation to effectively tackle the multidisciplinary objectives associated with battery housing. It leverages the triply periodic minimal surfaces lattices, aiming for high mechanical stiffness and efficient heat dissipation considering heat conduction and convection. The effectiveness of the proposed framework was demonstrated through the battery housing design, showcasing its ability to address multidisciplinary objectives as evidenced by the analysis of the Pareto front. This study identifies the potential of lattices in lightweight applications incorporating multiphysics and offers an efficient lattice design framework readily extended to other engineering challenges.

Corrosion Behavior and Mechanical Property of 5182 Aluminum/DP780 Steel Resistance Spot Welding Joints.

Corrosion behavior is critical to the application of lightweight aluminum/steel joints using new resistance spot welding (RSW) technology. The study investigated the corrosion mechanism and the shear strength of RSW joints comprising 1.2 mm 5182 aluminum and 1.5 mm DP780 galvanized steel. Electrochemical corrosion tests were conducted on the base materials and various positions of the welds in a 3.5% NaCl solution. This result revealed that the corrosion susceptibility of the interfacial intermetallic compound (IMC) layer was not accelerated by the aluminum nugget because of the noble corrosion potential. Subsequently, the spray acceleration test was employed to investigate the corrosion mechanism. It is noteworthy that microcracks, as well as regions enriched with silicon and oxygen at the interface front, are preferential to corrosion during salt spray exposure, instead of the IMC layer. Moreover, the shear strength of the joints decreases with the reduction in the effective joint area after the salt spray exposure of the weld joints. This research systematically explored the corrosion behavior and its relationship with the mechanical properties of Al alloy/steel RSW joints.

PRC6: Hybrid lightweight cipher for enhanced cloud data security in parallel environment

AbstractModern technologies of computing cloud are showing great promise, but at the same time create new security challenges that hinder full acceptance. Given that most of these services often use cloud networks as channels for communication, securing data transmission is crucial. This paper introduce a new hybrid encryption algorithm, the proposed two‐layered PRC6 cipher, tailored address security concerns in cloud computing environments with minimal resource constraints. The PRC6 cipher incorporates enhancements from Cha‐cha into an extension of the RC6 cipher. PRC6 implements double encryption. At the first level, the plain text is divided into four equal parts, each encrypted by processes derived from RC6, which include shifting, summation, modulo arithmetic, and XOR with a generated key. The second level incorporates a Quarter round function, among others, to further obscure the encoded message. PRC6 is implemented in a parallel computing model to significantly reduce overall computation time, especially important for lightweight applications. Experimental results show that the algorithm can achieve a high level of security for cloud workloads. It activates parallel mode in just seven encryption rounds, cutting calculation time to 50% in a matter of seconds. Performance evaluations against popular encryption standards also indicate that PRC6 offers promising security benefits when computational resources are limited. This hybrid approach presents a viable solution for strengthening data protection in modern cloud systems and it stand against the most popular attacks like brute force.

Topology optimization and bionic analysis of heat sink fin configuration based on additive manufacturing technology

Fins are extensively employed in heat sinks for high heat flux components. In this study, three distinct objective functions, namely temperature gradient minimization (TO-I type fin), average temperature minimization (TO-II type fin), and entransy dissipation minimization (TO-III type fin), are established for topology optimization design of the heat sink fin structure to effectively minimize the temperature of the heat source. By conducting a comparative analysis of the configuration features and thermal performance of optimized fins with different objective functions, it is evident that the TO-I type fin exhibits superior thermal performance. When the fin volume fraction φ is 0.3, the heat source center temperature of TO-I type fin is 2.67 K and 4.55 K lower than that of TO-II type fin and TO-III type fin, respectively. Meanwhile, the bionic analysis of the optimized fins under different objective functions using fractal theory reveals that the fractal dimension of the TO-I type fin is 1.4038, which is the closest to the average fractal dimension of many kinds of leaf veins in nature (D¯f= 1.3762), which indicates that the optimized fins have the bionic characteristics most similar to those of the leaf blade. Finally, the three topology optimization fins were fabricated using boundary-filtering optimization 3D printing technology. Comparative tests verified the advantage of minimizing the temperature gradient as the objective function of topology optimization and demonstrated its potential for thermal performance and lightweighting applications, especially under high heat source operating conditions.

Review on Aerated Lightweight Concrete Challenges and Application

This study explores the use of environmentally friendly Aerated Lightweight Concrete (ALC) in constructions, focusing on its versatility and adaptability to various densities. The growing demand for lightweight building materials with excellent strength-to-weight ratios has led to an expansion in the use of ALC over the past decade. The focus is on creating customized ALC for specific uses, rather than introducing novel materials. The article analyzes the primary variables affecting ALC use, such as raw materials, manufacturing processes, and anticipated density-based features. The review aims to demonstrate how ALC's physical and mechanical properties can be altered for building applications using new and alternative raw materials.

Impact of ply stacking sequence on the mechanical response of hybrid Jute-Banana fiber phenoplast composites

Natural fiber composites are increasingly gaining popularity as a cost-effective and environmentally friendly alternative to synthetic fibers. Incorporating a variety of fibers enhances mechanical properties. The arrangement of fibers plays a crucial role in determining the mechanical characteristics of laminate composites. Therefore, the primary objective of this study is to investigate how the stacking order of jute (J) and banana (B) fibers affects the mechanical behaviour of composites made from phenolic resins. Four different fiber mat stacking sequences (J/B/B/J, B/J/J/B, J/B/J/B, and J/J/B/B) were used for developing the eco-fiber composites using the heat-press technique. Several mechanical parameters were assessed, including tensile strength, flexural strength, impact strength, and inter-laminar shear strength (ILSS). The experimental results indicated that the JBBJ composite exhibits superior tensile strength (46.65 MPa) and modulus (993 MPa) compared to the other composites due to the presence of high-strength jute fibers on the surface. Additionally, the flexural strength of the JBBJ composite (87.24 MPa) was found to be noteworthy. It was observed that the impact strength of jute fibers surpasses that of banana fibers. Consequently, the JBBJ composite demonstrates higher values for energy absorption (0.482 J) and impact strength (120 J m−1) compared to the other composites tested. Moreover, the JBBJ composite displays higher inter-laminar shear strength and hardness values compared to BJJB, JBJB, and JJBB by 30%, 35%, and 43%, respectively. Scanning electron microscope microphotographs reveal strong correlational fracture failure mechanisms, indicative of improved mechanical properties in the JBBJ composite. Based on the experimental results, it is evident that the JBBJ composite can be utilized in lightweight applications.

Research progress and future prospects on high speed extrudable magnesium alloys: A review

Magnesium (Mg) and its alloys, as the lightest metal structural materials, are significantly attractive for lightweight applications. However, the extrudability of commercial Mg alloys is obviously poor compared with Al alloys, which has greatly restricted their widespread application so far. To further expand the industry uptake of Mg alloy extrusion components, development of the low-cost, high speed extrudable Mg alloys with good mechanical performance is strongly desired. In this review, the factors determining the extrudability of Mg alloys are critically analysed. Besides, recent research highlights on high speed extrudable Mg alloys are systematically reviewed from the perspective of the alloying systems, specifically focusing on Mg–Al, Mg–Zn, Mg–Sn, Mg–Bi and Mg–RE based alloys. Furthermore, the new alloy design concepts and novel extrusion processing routes are critically analysed and summarized, and also the recommendations for future research prospects for high speed extrudable Mg alloys are also suggested. We hope this review will inspire new ideas on both composition design and technology innovation for developing high speed extrudable Mg alloys with excellent strength-ductility synergy.

Improved ductility of hot extruded Mg-0.5Zn-0.5Zr-1RE alloy by Li addition

Mechanical properties of lean Mg-xLi-1RE-0.5Zn-0.5Zr alloys after hot working by the extrusion process were systematically investigated. By increasing Li content, the coarsening of the dynamic recrystallization (DRX) grain size (D) was recorded. This was ascribed to the decrease of the solidus temperature (TSolidus) by increasing Li content, and hence, the increase of the homologous temperature during hot deformation (T/TSolidus). As a result, the tensile yield stress (TYS), ultimate tensile strength (UTS), compressive yield stress (CYS), and ultimate compressive strength (UCS) decreased by increasing Li content. Accordingly, the Hall-Petch relationships of TYS = 145.8 + 69/√D and CYS = 69.3 + 100/√D were proposed, where TYS, CYS, and D are expressed in MPa, MPa, and μm, respectively. However, total elongation in the tension test and fracture strain in the compression test were significantly improved and the crystallographic texture intensity decreased by increasing the Li content. These improvements were found to be quite beneficial for overcoming and breaking the strength–ductility trade-off. The mechanical behavior of these alloys was compared to other competitive alloys for lightweight applications.

Synthesis and characterization of chicken feather derived rachis fiber-bamboo particulate hybrid reinforced epoxy composites for sustainable structural applications

Purpose This paper aims to reduce waste management and generate wealth by investigating the novelty of combining chicken feather fiber and bamboo particles to produce hybrid biocomposites. This is part of responsible production and sustainability techniques for sustainable development goals. This study aims to broaden animal and plant fiber utilization in the sustainable production of epoxy resins for engineering applications. Design/methodology/approach This research used two reinforcing materials [chicken feather fiber (CFF) and bamboo particles (BP)] to reinforce epoxy resin. The BPs were kept constant at 6 Wt.%, while the CFF was varied within 3–15 Wt.% in the composites to make CFF-BP polymer-reinforced composite (CFF-BP PRC). The mechanical experiment showed a 21% reduction in densities, making the CFF-BP PRC an excellent choice for lightweight applications. Findings It was discovered that fabricated composites with 10 mm CFF length had improved properties compared with the 15 mm CFF length and pristine samples, which confirmed that short fibers are better at enhancing randomly dispersed fibers in the epoxy matrix. However, the ballistic properties of both samples matched. There is a 40% increase in tensile strength and a 54% increase in flexural strength of the CFF-BP PRC compared to the pristine sample. Originality/value According to the literature review, to the best of the authors’ knowledge, this is a novel study of chicken fiber and bamboo particles in reinforcing epoxy composite.

Single-metalens-assisted polarization imaging and edge detection for target recognition

Simultaneous capture of various light information, including polarization and edge information of the objects, has consistently been a fundamental concern within the field of target recognition. However, these tasks are typically accompanied by bulky optical components and active illumination methods, which significantly restricts their use in compact and lightweight applications. Here, we demonstrate a metalens-assisted imaging system that can simultaneously achieve polarization imaging and optoelectronic edge detection in a single shot with low consumption. The dielectric metalens is designed to achieve polarization imaging by dispersing the input polarized light into two orthogonal components, resulting in optoelectronic isotropic edge detection of two-dimensional images after digital post-processing. Compared with the algorithmic methods using a convolution kernel, the proposed system has a much lower computational complexity. The work presented in this study demonstrates the potential applications in machine vision and paves the way for the development of compact target recognition and real-time image processing systems.

Integrating Experimental and Computational Analyses for Mechanical Characterization of Titanium Carbide/Aluminum Metal Matrix Composites.

This study investigates the mechanical properties of titanium carbide/aluminum metal matrix composites (AMMCs) using both experimental and computational methods. Through accumulative roll bonding (ARB) and cryorolling (CR) processes, AA1050 alloy surfaces were reinforced with TiCp particles to create the Al-TiCp composite. The experimental analysis shows significant improvements in tensile strength, yield strength, elastic modulus, and hardness. The finite element analysis (FEA) simulations, particularly the microstructural modeling of RVE-1 (the experimental case model), align closely with the experimental results observed through scanning electron microscopy (SEM). This validation underscores the accuracy of the computational models in predicting the mechanical behavior under identical experimental conditions. The simulated elastic modulus deviates by 5.49% from the experimental value, while the tensile strength shows a 6.81% difference. Additionally, the simulated yield strength indicates a 2.85% deviation. The simulation data provide insights into the microstructural behavior, stress distribution, and particle-matrix interactions, facilitating the design optimization for enhanced performance. The study also explores the influence of particle shapes and sizes through Representative Volume Element (RVE) models, highlighting nuanced effects on stress-strain behavior. The microstructural evolution is examined via transmission electron microscopy (TEM), revealing insights regarding grain refinement. These findings demonstrate the potential of Al-TiCp composites for lightweight applications.

Effect of Geometrical Parameters on the Mechanical Performance of Bamboo-Inspired Gradient Hollow-Strut Octet Lattice Structure Fabricated by Additive Manufacturing.

Hollow-strut metal lattice structures are currently attracting extensive attention due to their excellent mechanical performance. Inspired by the node structure of bamboo, this study aimed to investigate the mechanical performance of the gradient hollow-strut octet lattice structure fabricated by laser powder bed fusion (LPBF). The effect of geometrical parameters on the yield strength, Young's modulus and energy absorption of the designed octet unit cells were studied and optimized by FEA analysis. The hollow-strut geometrical parameters that deliver the best mechanical property combinations were identified, and the corresponding unit cells were then redesigned into the 3 × 3 × 3 type lattice structures for experimental evaluations. Compression tests confirmed that the designed gradient hollow-strut octet lattice structures demonstrated superior mechanical properties and deformation stability than their solid-strut lattice structure counterparts. The underlying deformation mechanism analysis revealed that the remarkably enhanced bending strength of the gradient hollow-strut lattice structure made significant contributions to its mechanical performance improvement. This study is envisaged to shed light on future hollow-strut metal lattice structure design for lightweight applications, with the final aim of enhancing the component's mechanical properties and/or lowering its density as compared with the solid-strut lattice structures.

Grain refinement induced unusually large shape memory effect in lightweight titanium alloy

High-performance and lightweight shape memory alloys (SMAs) play a pivotal role in a variety of cutting-edge fields like aerospace, which however, are still quite difficult to be obtained until now. In the present work, we meticulously develop a novel lightweight Ti-12.5V-3.5Al-1Hf-0.8Fe-0.01B (at.%) SMA, which has a low mass density of ∼4.73 g/cm3. Prominently, distinct from the conventional wisdom in previous studies that is mainly based on eliminating grain boundaries or developing desired texture, we utilize the grain refinement strategy introduced by elaborate thermal-mechanical training, which effectively enables us to achieve exceptional shape memory response and strength-ductility combination simultaneously. It was revealed that a dominant β phase structure is achieved in this newly designed fine-grain SMA, accompanied by some α″ variants penetrating the grain boundaries. Compared to the coarse-grained counterpart, the deformation process becomes more intricate, involving stress-induced martensitic transformation and additional reorientations, which ultimately results in an unusually large recoverable strain up to 9.3 %. Furthermore, the fine-grain structure also contributes to an enhanced specific yield strength up to ∼159 MPa·m³/kg, while maintaining a large tensile ductility of ∼30 %. In light of its impressive structure-function integration and cost efficiency, this new-type SMA would emerge as a promising candidate for various advanced lightweight applications in a broad spectrum of fields.

Enhanced strength and ductility of aluminum alloy laser welded joints through Ca micro˗alloyed welding materials

Aluminum alloy is widely used in high˗speed train bodies. However, compared with the base material, the tensile strength and elongation of its laser welded joints are significantly reduced, which limits the lightweight application of the next generation of high˗speed trains. The research in this article indicates that laser welding with Ca micro˗alloyed 5356 filler metal has changed the mechanical properties and microstructure of the weld seam. Without the Ca in the filler metal, the strength and elongation of the laser welded joint are only 215.5 MPa and 3.1 %. When the Ca content in the filler metal reaches 0.04 wt%, the laser welded joint has high tensile strength and maximum elongation, which are 251.5 MPa and 9.7 %, respectively. As the Ca content increases, the grain size of the welded joint gradually decreases, and the limiting effect of Ca element on the growth of α˗Al grains is the main reason for grain refinement. In addition, the addition of Ca transforms the coarse Fe˗rich phase in the weld into a fine˗grained second phase, while promoting the formation of deformable nanoparticles γ˗Al12Mg17, leading to the accumulation of dislocations and successfully improving the strength and plasticity of laser welded joints. When the Ca content further increases, the second phase grows, and the tensile strength and plasticity of the joint slightly decrease, but are still higher than that of the joint without Ca.

Gear-Shaped High-g Combustion Chamber for Micro Turbojet Engine Applications.

Enhancing combustion efficiency and optimizing the thrust-to-weight ratio are critical technical challenges encountered in the development, application, and growth of micro turbojet engines. The high-centrifugal (high-g) combustion chamber, as an innovative combustion chamber system, has the capability to replace the primary combustion chamber of the traditional turbojet engine, reducing the length of the combustion chamber while maintaining engine performance. Previous studies on the structure of the high-g combustor (HGC) have shown problems such as uneven temperature distribution of the turbojet rotor. To improve the feasibility of HGC integration into micro turbojet engines, this study conducts relevant experiments on a 120 N thrust engine. Subsequently, the results of these experiments were used to analyze the structural design of HGC through a simulation approach. Including six main configurations, the first four structural designs focused on establishing a suitable highly centrifugal environment to stabilize and improve the combustion performance, which was successfully achieved by designing the outer ring gear-shaped inlet with four different angles. Subsequent structural designs were based around improving the uniformity of the temperature distribution at the combustion chamber outlet. The final design of the HGC combustion efficiency is not much different from the original combustion chamber, and it can shorten the axial length of the combustion chamber by nearly 30%. The design of the air inlet holes and the baffle plate effectively improves the temperature uniformity at the outlet of the combustion chamber. Moreover, without changing the combustion chamber material, the corresponding engine weight can be reduced by about 10.7%, and the engine thrust-to-weight ratio can be improved by up to 12% with the same thrust, which provides design ideas for further lightweight applications.

Capacity Building of Thermal Conductivity in Polymers and Their Composites: A Short Review of the Effect of Various Fillers in Their Composites

In industries like automotive, packaging, structural, electrical, and energy harvesting, polymers and polymer composites have been the preferred material due to their lightweight and long-lasting applications. They are potential replacements for the metal structures used in communication devices, microelectronics, electric vehicles, and generators due to their adaptability and flexibility. However, most of the polymers are not thermal conductors and it difficult to use them in application such as high-performance computing systems, aerospace and electronics. The capacity building of thermal conductivity in the polymers and their composites are current objectives in various applications as compared with metals due to the many advantages of polymers; viz. corrosion resistance and ease of processing. Our study of the literature, as described, here outlines three main features, (a) Various fillers in polymer composites play important roles in the effective thermal conductivity, (b) the effect of filler percentage in thermal conductivity, and (c) various processing method and their effect on the thermal conductivity. This review was aimed to benefit the recent trend of industrial requirements and to highlight the fillers used in polymer composites for various applications.

3-D woven honeycomb structures and their composites

Honeycomb is regarded as a valuable structural material because of its high strength, shear stiffness, high impact strength, low weight, high crushing stress, and nearly constant force to crush. It is a cellular solid, well-known as a core in creating sandwich structures for use in structural composites. Honeycombs are often utilized in the aircraft sector as the core of sandwich panels and in the automotive industry as effective impact attenuators because of their superior mechanical performance. The hollow spaces in the honeycomb structure not only reduce weight but also ensure the required strength, provided they are designed correctly. In lightweight application areas, because they offer structural integrity, 3-D woven honeycomb composites have a bright future and possess the potential to replace aluminum and other metal alloys. This issue of Textile Progress focuses on the manufacturing of 3-D woven honeycomb fabrics, their mechanical characterization, application areas, different ways of weaving honeycomb cells, and some innovations related to honeycomb-like auxetic and 3-D printed honeycomb structures.

A Review of Non-wood Lignocellulose Waste Material Reinforced Concrete for Light-weight Construction Applications

In recent decades, non-wood lignocellulosic materials have gained significant attention, particularly in concrete applications for construction purposes. This study delves into utilising non-wood lignocellulosic materials for reinforcing concrete in construction applications. Lignocellulosic material emerges as a promising option for formulating new fibre cement compositions, thereby enhancing the sustainability, affordability, and performance of construction materials. Moreover, this research broadens the horizons of recycling agricultural waste by facilitating rational disposal and optimal utilisation. Through a comprehensive review, the study reveals that flax fibres, coir pith, prickly pear fibres, and rice husk ash waste exhibit superior workability compared to their counterparts. Furthermore, the strength of non-wood lignocellulosic reinforced concrete, incorporating bagasse ash, rice husk ash, and nutshell ash, peaked when fine aggregate replacement reached 15%, surpassing other types of non-wood lignocellulosic reinforced concrete. Adding a small quantity of prickly pear fibre to cement enhances the thermal conductivity of concrete, consequently improving compressive strength, flexural strength, tensile strength, and elastic modulus. This research is relevant to international research as it advances sustainable construction materials with desirable properties, benefiting society and various industries.