This study investigates the fabrication and characterization of Al alloy matrix composites reinforced with graphene oxide (GO) using accumulative roll bonding (ARB). The annealed Al 6061 sheets were processed through 5-pass ARB with GO reinforcement applied during the initial passes. Scanning electron microscopy revealed effective mitigation of GO agglomeration and improved interface bonding due to microscale material mixing. Raman spectroscopy confirmed the strong interaction between GO and the Al alloy matrix, as evidenced by the increased D band intensities and enhanced 2D band symmetry. Mechanical testing indicated an approximately 338.37% increase in yield strength (YS) and 86.42% improvement in hardness for the ARB-processed (ARBed) Al 6061/GO composite (0.2wt%) compared with annealed Al 6061 and an approximately 14.15% increase in YS and 17.23% improvement in hardness for the ARBed Al/GO composite (0.2wt%) compared with unreinforced ARBed Al 6061 specimens after five passes. X-ray diffraction analysis indicated an increased dislocation density, corroborating the observed enhancements in mechanical properties. Fracture surface analysis revealed reduced elongation with deep dimples, highlighting the tradeoff between strength and ductility. These results demonstrate the effectiveness of ARB for integrating GO into the Al 6061 matrix to improve the mechanical performance and interfacial bonding and underscore its potential for advanced composite materials.

Friction stir welding (FSW) is an advanced solid-state joining technique that has transformed the fabrication of both similar and dissimilar metallic materials. Unlike conventional fusion welding, FSW joins materials below their melting temperatures, thereby minimizing common welding defects such as porosity, hot cracking, excessive distortion, and the formation of undesirable intermetallic compounds (IMCs). Owing to these advantages, FSW has emerged as a preferred joining process for dissimilar metal combinations, including aluminum–magnesium (Al–Mg), aluminum–copper (Al–Cu), aluminum–titanium (Al–Ti), and aluminum–steel (Al–steel), which are increasingly used in aerospace, automotive, marine, railway, and defense applications to produce lightweight, high-performance structures. Extensive research has been conducted to overcome the challenges associated with dissimilar FSW. For Al–Mg and Al–Cu joints, the primary concerns include excessive IMC formation, galvanic corrosion, and accelerated tool wear. In contrast, Al–Ti and Al–steel combinations are particularly difficult to weld because of their large differences in hardness, melting temperature, and thermal conductivity, which adversely affect material flow, interfacial bonding, and tool life. To address these challenges, several innovative approaches, such as double-pass FSW, stationary shoulder tools, interlayer-assisted welding, and hybrid processing techniques incorporating interfacial coatings, have been developed. These advancements have significantly improved weld quality, mechanical performance, and process reliability. Computational models have been widely used to simulate heat generation, material flow, strain distribution, and residual stress evolution, enabling better prediction of defect formation, IMC growth, and process optimization. Furthermore, advanced characterization techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and nanoindentation, have provided valuable insights into microstructural evolution, phase formation, mechanical behavior, and fracture mechanisms of dissimilar joints. This review presents a comprehensive and critical assessment of recent developments in the FSW of dissimilar metals. It systematically discusses the influence of material combinations, welding parameters, interlayer materials, and post-processing treatments on joint performance. The review also highlights persistent challenges, including brittle intermetallic formation and thermal and mechanical property mismatches, while evaluating current strategies for mitigating these issues. Comparative figures and tables summarize the reported mechanical properties, microstructural characteristics, and corrosion behavior under various processing conditions. By consolidating recent advances and identifying existing research gaps, this review provides valuable guidance for future investigations aimed at developing reliable, defect-free, and high-strength dissimilar metal joints to meet the evolving demands of next-generation manufacturing and lightweight engineering applications.

This study investigates the effect of heat treatments on the fatigue behavior of AZ31B magnesium alloy. Fatigue tests were performed on as-received (AR) samples, air-cooled (AC) samples, and water-quenched (WQ) samples at load ratios of R = 0.1 and 0.5. The results indicate that heat treatment significantly influences fatigue crack growth, with WQ samples exhibiting the lowest crack growth rates and longest fatigue lives at both load ratios. This improvement is attributed to microstructural refinement and residual stresses induced by rapid cooling. Field emission scanning electron microscopy (FE-SEM) analysis revealed that WQ samples possess finer microstructures, well defined crack paths, and mixed fracture modes, indicating a predominantly brittle yet more resistant crack propagation mechanism. Fractography showed localized plastic deformation and increased crack sensitivity in WQ samples due to high dislocation density and suppressed recovery. Electron Backscatter Diffraction (EBSD) analysis confirmed strong basal texture along the [001] direction in all samples, with the WQ sample showing more intense clustering near [0001], and well-defined texture. In contrast, the AC sample exhibited broader orientation spreads toward prismatic [10 1 0] and pyramidal [211 0] directions, suggesting greater activation of multiple slip systems. Overall, water quenching enhances fatigue performance through refined microstructure and favorable crystallographic orientation.

This study investigated the enhancement of mechanical and physical properties of 6061 aluminum alloy by employing friction stir additive manufacturing (FSAM), producing a multilayer composite reinforced with eggshell and graphene particles. A square high-speed steel tool ensured homogeneous dispersion of these reinforcements in the matrix. By varying reinforcement proportions, the composite attained significant property improvements: hardness increased by 26.7

Greenhouse drying is an effective and sustainable method for preserving high-moisture crops. While previous studies have mainly focused on structural and geometric modifications of greenhouse dryers, the role of internal surface properties under natural convection conditions remains insufficiently explored. In this study, a single-slope natural convection greenhouse dryer (SSNCGHD) was experimentally evaluated under three internal surface configurations: transparent (TSC), reflective (RSC), and absorptive (ASC). Drying experiments were performed on carrot, spinach, and tomato to represent solid, leafy, and juicy crops, respectively. Among the configurations, RSC produced more stable thermal conditions, reducing drying time by 11–24% compared with TSC. Moisture content decreased from 88% to 5% (carrot), 93% to 7% (spinach), and 95% to 9% (tomato, w.b.). Overall drying efficiencies of 69.8%, 72.4%, and 52% under RSC, respectively. Six drying models were tested, among which the Midilli and Kucuk model showed the closest agreement with experimental values. The capital cost increased from $57.02 (TSC) to $65.48 (RSC) and $60.71 (ASC), while economic analysis shows payback periods of 0.7–2.0 years and benefit-cost ratios of 8.01–23.37. The findings support low-cost, scalable, and passive solar drying of high-moisture crops.

In this manuscript, experiments have been performed on an evacuated tube collector indirect solar dryer (ETCISD) and a natural convection greenhouse dryer (NCGHD), across three vegetables (carrot, spinach, tomato) and varying crop loads (2.5, 5, and 10 kg) at the National Institute of Solar Energy, Gurugram, India (March-May 2025), with real-time monitoring of solar irradiance, chamber conditions, drying kinetics, moisture ratio, and visual assessment of microbial spoilage. Vegetables were dried from initial moisture contents of 88 % (carrot), 92.6 % (spinach), and 95 % (tomato) to safe levels of 5 %, 7 %, and 9 % on a wet basis, respectively. The NCGHD consistently maintained higher chamber temperatures (15-20 degrees C above ETC-ISD, peaking at 71.8 degrees C), resulting in 28-35 % faster drying and 1.7-2.5 times higher drying efficiency. While the ETC-ISD provided uniform thermal distribution, its higher internal humidity occasionally led to fungal development in tomatoes during extended drying. An economic assessment indicates that the initial cost of the NCGHD is around 78.5 % lower than that of the ETC-ISD. Overall, the results highlight the suitability of drying systems for decentralised solar drying aligned with Sustainable Development Goals (SDGs) 2 (Zero Hunger), 7 (Affordable and Clean Energy), and 9 (Industry, Innovation, and Infrastructure).

A systematic procedure is presented to determine the gradient energy coefficient and height of double-well potential (phase-field model parameters). The well-known Allen-Cahn equation is used to investigate cation interdiffusion in solid oxide fuel cell (SOFC). An established procedure that commonly applied in the study of solidification is adapted. The phase-field model parameters are determined under sharp as well as thin interface limits. The upper limit of the interface thickness is deduced for the thin interface limit. Effect of variation of interface thickness for a particular value of interfacial energy is evaluated on the cation interdiffusion in terms of interdiffusion length of the cations under thin interface limit and this is compared with that of sharp interface limit. Effect of variation of interfacial energy at the upper limit of the interface thickness is also studied under the thin interface limit. Further, the reason behind the variation of interdiffusion length is also presented under the thin interface limit for different values of interfacial energy. Under a large variation of interfacial energy, no significant changes are found in the interdiffusion length of the cations. From this study, it can be deduced that for a considerable range of interfacial energy, a wider range of model parameters can be selected for the phase-field model with reasonable accuracy.

We demonstrate quarter phase grating cavity in SOI Substrate showing High quality factor. Grating period of 290 nm repeated 862 times with a cavity in between of length 145 nm integrated in SOI waveguide was theoretically plotted in MATLAB and the spectral result was compared with Finite Differential Time Domain simulation. The wavelength characteristic of the device showed a cavity resonant wavelength at 1608 nm with 21 pm bandwidth, resulting in the quality factor in the order of 10 ^4 .

A significant amount of work has been carried out to study the effect of temperature at the battery level. However, its effect at the particle level has not been investigated extensively. Further, the effect of heterogeneity of solid electrolyte interphase (SEI) layer is not given much attention. It is decisive in the stability of the SEI layer. Motivated by these facts, to study the effect of heterogeneity of SEI layer along with temperature on chemo-mechanical stresses within a silicon anode particle, a mathematical model is developed based on the finite deformation theory, together with the incorporation of plasticity. The effect of temperature on the stresses, with and without heterogeneous SEI layer, is also discussed. The heterogeneity of the SEI layer significantly alters the stresses in the inorganic part of the SEI layer as compared to the homogeneous assumption of the SEI layer. Additionally, the impact of various parameters on peak hoop stress found in the SEI layer is also investigated. The radial and hoop stresses in the particle without SEI layer considering temperature variation are found to be less as compared to without considering temperature variation. This study can help in identifying important properties for designing a superior artificial SEI for the better performance of Li-ion batteries.

This manuscript endeavors to elucidate a comprehensive analysis for the assessment of thermal efficiency in double pass solar air collectors augmented with fabricated roughness, instrumental in the generation of heated air for applications in heating and drying. The analytical procedure delineates comparisons between a smooth and a double-sided, roughened absorber, characterized by discrete, multi V and staggered configurations of roughness. The analysis was performed for different roughness parameters including relative roughness width (W/w) from 4 to 8 and relative staggered rib size (r/e) from 1 to 4 and relative rib pitch (p '/p) from 0.2 to 0.8 while other parameters were kept constant. The research scrutinizes the impact of a constellation of parameters: the temperature rise coefficient (Delta T/I, varying between 0.002 and 0.02 K-m(2)/W), Reynolds number (Re, spanning 2000-20,000), solar irradiance (I, ranging from 600 to 1000 W/m(2)), and the geometric variables of the artificial roughness, on both the thermal efficiency and efficiency enhancement factor of the collector. The study revealed that the roughened collector exhibits higher thermal efficiency compared to smooth collector for a similar condition. The extreme enhancement in thermal efficiency of the collector with roughness has been found to be 56.75% more than nonroughened collector for Re = 2000. A further observation was made that thermal efficiency has increased sharply for lower flow rate (Re < 10,000) whereas for higher flow rates (Re > 10,000), this increase becomes nearly asymptotic. In addition, the efficiency enhancement factor has also been found to increase with an increase in Delta T/I. A peak value of 2.321 has been found to be obtained for the efficiency enhancement factor for Delta T/I = 0.02 K-m(2)/W and I = 1000 W/m(2) as a result of the studies conducted.

This study provides the prediction that plastic pyrolysis oil (PPO) is equivalent to petroleum diesel in CI engines. The four input parameters have been considered to enhance performance and reduced emissions. The input parameters of engine trials, like fuel blend (PPO and diesel), compression ratio, nanoparticle concentration, and injection timing, were studied with the response surface methodology (RSM) using the central composite rotating design (CCRD) matrix. The main goal is to identify the ideal values of input parameters that will provide the highest achievable brake thermal efficiency (BTE), the lowest possible brake-specific fuel consumption (BSFC), and the lowest possible emission like carbon monoxide (CO), unburnt hydrocarbons (HC) and nitrogen oxides (NOx). The optimal engine output responses for BTE, BSFC, in-cylinder pressure, heat release rate (HRR), and ignition delay, respectively. Along with a composite desirability of 0.89 under optimum operating conditions. After the regression analysis, 16.56% PPO blend ratio, 53.53 ppm Al2O3 nanoparticle concentration, 18.06 compression ratio, and 20.95 degrees bTDC injection timing were received the optimized engine settings. Optimal engine input parameters were validated through actual engine trials and compared with optimized responses and found satisfactory and acceptable errors (less than 5%). The current study establishes vital input parameters providing the best engine performance, combustion characteristics, and lower emissions during engine trials. So current investigation declared PPO with Al2O3 nanoparticles is potential fuel for the CI engine.

High specific strength and good fatigue limit are the key properties to watch out during development of aerospace components. Aluminum composites are proven high specific strength materials especially graphene embedded composites worth a mention in this context. While, surface finish is an eminent parameter affecting fatigue strength of a component showcasing the importance of machining technique employed to transform a fabricated bulk into finished product. Current study, therefore emphasizes on electrical discharge machining (EDM) of aluminum composites embedded with graphene nanoplatelets (1.5 wt.%) fabricated through a hybrid approach of blending solid and liquid metallurgical routes. Further, mathematical and neurological forecast models are developed to individually predict the machining response variables namely surface roughness (SR), material removal rate (MRR) and tool wear rate (TWR). Among machining parameters current (I), pulse on-time (Ton), pulse off-time (Toff) and flushing pressure (P) considered; Ton is noted to greatly influence the surface quality of composite while TWR and MRR are affected by current during ANOVA analysis. On comparative understanding of forecast models, neurological models outperform quadratic non-linear mathematical models where accuracy of prediction achieved by developed artificial neural network (ANN) model is 96% for surface roughness. The error performance plots, error histograms and overall fit plots depict a marginal over-fit neurological model. However, significantly high coefficient of correlation (R) of 99% possessed by ANN model illustrates their potential in forecasting response parameters.

The heat generated by electronic components can lead to the failure of the system, so an efficient cooling system is needed. The present study introduces a novel approach to analyze the impact of design parameters on the performance of pin–fin heat sinks under varying input heat loads. This work aims to numerically investigate the thermal performance of center-cleared pin-fin heat sinks (PFHS) under natural convection. PFHS having solid, hollow, and perforated hollow cylindrical fins were investigated under varied power input in the range of 2.15–10.75 W. Solid cylinder PFHS showed least thermal resistance of 6.87 K W−1 and the lowest base temperature of 41.11 ºC corresponding to the power input of 10.75 and 2.15 W, respectively. The maximum effectiveness of 3.3 corresponds to solid cylinder PFHS at 4.3 W. The maximum volumetric heat dissipation is observed in case of a hollow cylinder PFHS, and minimum value of (Rth m) is found for the perforated hollow cylinder PFHS.

The generation of plastic waste and waste cooking oil is a serious environmental concern because of worldwide waste disposal issues. At the same time, increasing demand and contemporary geopolitics make fossil fuels a significant worldwide problem. As a result, there has been an increase in demand for alternate fuel for CI engines. To overcome these twin problems can be addressed by converting waste into liquid fuels. This research explores an intriguing area by mixing waste cooking oil biodiesel and waste plastic oil to create a mixture that remarkably seems like the physico-chemical properties of diesel fuel in a society that is looking for sustainable alternatives. So, in this investigation, a ternary fuel blend of Petro-diesel, waste cooking oil biodiesel (WCOB), and waste plastic oil (WPO) was used in the diesel engine. To enhance the properties of fuel, combustion, emission, and performance parameters of diesel engines, a ternary blend of B20P20D60 was employed in the CI engine as an alternative fuel. In the ternary fuel blends, WCOB, WPO, and diesel content were 20%, 20%, and 60%, respectively. The results were compared with conventional diesel fuel, showing that the ternary fuel blend B20P20D60 has an improved brake thermal efficiency of up to 1.71% at 80% loading and reduced emissions (HC, CO, NOx) compared to conventional diesel. Because of this, the ternary blends have significant potential for use in diesel engines.

Impact problems have always been a field of interest for researchers. Practical problems involve large amount of heat generation due to plastic deformation. In this paper, we have studied monolithic and multi-layered target being impacted by rigid projectile using finite element method. Two different materials—1100-H14 aluminium and Weldox 700 E steel—are layered up as target. The influence of thickness of layer, number of layers, and temperature softening on the ballistic phenomena are studied using Finite Element Package ABAQUS/ Explicit. To include the thermal softening effect, the dynamic temperature displacement explicit model is used for the finite element analysis. The targets are modelled using Johnson–Cook material model and Johnson–Cook fracture model. Projectile shapes such as ogival and conical are used for comparison of ballistic resistance of each configuration. The analysis with monolithic target showed that the failure mechanism in both the cases—conical and ogival-shaped projectile—involved hole enlargement and petal formation. Multi-layered configuration of aluminium layer in front and steel layer at back showed more obstruction. For ogival projectile, the target failure involves ductile hole enlargement and petalling, whereas conical projectile caused target to fail by ductile hole enlargement and plugging. As the frontal portion of projectile changes from conical to blunter shape, failure mechanism transforms from petalling to plugging. It was observed that with decrease in impact velocity and decrease in number of layers, velocity drop increased. © 2016 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of the organizing committee of Implast 2016. © 2016 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of the organizing committee of Implast 2016.

The uncontrolled exploitation of non-renewable energy resources like fossil fuels not only depletes the resources but also pollutes the environment through enormous greenhouse gas emissions (GHGs). Therefore, sustainable, clean, and safe energy like solar energy is in huge demand. One of the major setbacks for this form is the low conversion efficiency of the Photovoltaic (PV) panels. The operating temperature has a great impact on this. As the temperature of the panel increases the efficiency and durability of the panel degrades. To enhance the efficiency, different cooling approaches are suggested. In this study, a passive cooling method using Copper fins attached to the back side of the PV panel is evaluated. The numerical model is created using Abaqus/CAE software using computational fluid dynamics (CFD) simulation with the incorporation of fluid–structure interaction (FSI). Many studies have reported the numerical equations used to predict the operating temperature of a solar panel, which is validated by various experimental data communicated in the literature, and the simulation is carried out with this information. Further, the optimum operating temperature and conversion efficiency of the solar PV panels are estimated based on numerous fin parameters (length, thickness, shape) for a specified atmospheric condition.

Thermal management of electronic components is becoming popular due to the extensive applications of electronic components in modern machines and automobiles. Natural convection heat transfer is preferred for electronic cooling in the unavailability of power supply or where high energy efficiency is desirable. Pin fin heat sinks offer effective cooling of such electronic devices even with the natural convection mode. Center-cleared pin-fin heat sinks offer better thermal management of a heated surface compared to conventional pin-fin heat sinks. The present work numerically investigates the thermal characteristics of center cleared solid cylinder, solid tapered, hollow tapered, and perforated hollow tapered pin fin heat sinks under natural convection. The numerical results are discussed in the form of steady state base temperature, heat transfer coefficient, mass-multiplied thermal resistance, volumetric heat dissipation rate, and effectiveness of different pin fin heat sink designs under varying power input from 2.15 to 10.75 W. The minimum mass-multiplied thermal resistance (RThM) is found to be 0.11 K.kg/W and the maximum volumetric heat dissipation rate is 1750.3 KW/m(3) corresponding to the perforated hollow tapered pin fin heat sink design.