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Poly-aluminium chloride (PAC) sludge is a waste product created during drinking water treatment, usually generated in large quantities and typically landfilled. More attention must be directed to environmental-friendly management and economically sustainable of Al-based sludge. In this work, a low-cost and environmental-friendly adsorbent prepared by sodium alginate coated PAC sludge (SPS) was investigated for fluoride removal. Basic preparing parameters including heating temperature (200–800°C), sodium alginate concentration (0.5–5 wt%), particle size (1–2 mm, 2–3 mm, 3–4 mm) and operating parameters including dosage (1–14 g/L), solution pH (4–11), temperature (10–35°C), co-existing anions (NO3−, Cl−, SO42-, PO43-) were examined to evaluate the optimum defluoridation capacity. The prepared SPS adsorbents reached a high removal efficiency of 95.6% with initial fluoride concentration of 10 mg/L, dose of 8 g/L, contact time of 24 h, pH value of 7 and temperature of 10°C. The kinetic study indicated that fluoride adsorption followed the pseudo-second-order kinetics well (R2 = 0.9942), and adsorption isotherms can be well described by Freundlich model (R2 = 0.9952). Thermodynamic studies showed the fluoride adsorption was spontaneous and exothermic. The elements and functional groups of SPS adsorbents were analysed by using EDS and FTIR, respectively. The adsorption mechanism involved physisorption, ligand-exchange and electrostatic attraction. According to N2 adsorption–desorption isotherm, the SPS was mesoporous material which facilitated the adsorption of fluoride ions. Also, aluminium presented in form of Al-OH in SPS adsorbents had significant contribution in fluoride adsorption. The concentration of the residual aluminium ions was 4.48 × 10−3 mg/L which is lower than the China Drinking Water Standard. The encouraging results of this preliminary study indicated that SPS is an environmental-friendly and cost-effective treatment option for groundwater with fluoride pollution. [ABSTRACT FROM AUTHOR]

This study aims to solve the problem of springback control of aluminum alloy components in the rolling process, and the method of combining experiment and simulation is adopted. Firstly, a series of aluminum alloy samples are designed, and the four-axis flexible bending machine is used for precision roll bending. Secondly, the three-dimensional (3D) shape change data of the workpiece before and after roll bending is monitored and recorded in real-time by a high-precision 3D scanner. Meanwhile, aiming at different rolling process parameters of each group (including roll bend speed, feed rate, pre-deformation amount, mold curvature radius, and other factors), advanced finite element software is used to carry out detailed simulation and calculations. In addition, the coincidence is compared and analyzed between the actual experiment results and the simulation prediction. The stress-strain distribution and springback evolution of aluminum alloy during roll bending are described accurately. The experimental and simulation results show that the springback rate of aluminum alloy fluctuates in the range of 5% to 15% after four-axis flexible roll bending, and the specific springback value is influenced by various process parameters. For example, under the premise of keeping other conditions unchanged, when the roll bending speed is increased from 30mm/s to 60mm/s, the springback rate shows an upward trend of about 3%. By increasing the feed rate by 20%, an average decrease of about 7% in springback quantity is observed. It can be seen that the increase in roll bending speed can aggravate the springback phenomenon, and the appropriate increase in feed rate can play a certain role in restraining the springback. Further analysis shows that the choice of the mold curvature radius and pre-deformation amount also has a decisive influence on the springback characteristics. There is a nonlinear relationship between the two parameters and the amount of springback. Changing these two parameters in a specific range can effectively regulate the springback effect. [ABSTRACT FROM AUTHOR]

Recycling of composite materials is an important global issue due to the wide use of these materials in many industries. Waste management options are being explored. Mechanical recycling is one of the methods that allows obtaining polyester–glass recyclate in powder form as a result of appropriate crushing and grinding of waste. Due to the fact that the properties of composites can be easily modified by adding various types of fillers and nanofillers, this is one of the ways to improve the properties of such complex composite materials. This article presents the strength parameters of composites with the addition of fillers in the form of polyester–glass recyclate and a nanofiller in the form of gamma-phase aluminum nanopowder. To analyze the obtained results, Kolmogorov-Sinai (K-S) metric entropy was used to determine the transition from the elastic to the viscoelastic state in materials without and with the addition of nanoaluminum, during a static tensile test. The tests included samples with the addition of fillers and nanofillers, as well as a base sample without any additives. The article presents the strength parameters obtained from a testing machine during a static tensile test. Additionally, the acoustic emission method was used during the research. Thanks to which, graphs of the effective value of the electrical signal (RMS) were prepared as a function of time, the parameters were previously identified as extremely useful for analyzing the destruction process of composite materials. The values obtained from the K-S metric entropy method and the acoustic emission method were plotted on sample stretching graphs. The influence of the nanofiller and filler on these parameters was also analyzed. The presented results showed that the aluminum nanoadditive did not increase the strength parameters of the composite with recyclate as a result of the addition of aluminum nanofiller; however, its addition influenced the operational parameters, which is reflected in a 5% increase in the UTS value (from 55% to 60%). [ABSTRACT FROM AUTHOR]

Aluminum alloy forms a protective layer of aluminum oxide when exposed to air, which gives it corrosion resistance. But, the layer can be easily damaged, causing metal corrosion. The hard anodizing method is used to solve this issue. Determining the appropriate anodizing parameters, including current density, process time, and electrolyte concentration, is crucial for attaining the desired thickness and hardness of the anodized layer. An experimental design approach utilizing the response surface method (RSM) was employed to investigate the effects of these variables. Quadratic models were presented to predict the hardness and thickness of the layer with an average error of 2.84% and 3.89%, respectively. The models were verified through analysis of variance (ANOVA) to assess the effect of each parameter and their interactions. Oxalic acid concentration, the interaction between process time and oxalic acid concentration, and the square of current density and process time have a significant impact on hardness. Layer thickness is mainly influenced by current density, process time, and the interaction between process time and oxalic acid concentration. Optimization results show that a current density of 1.19 A / dm 2 , a process time of 160 min, sulfuric and oxalic acid concentrations of 26.25 g r / l i t and 36.88 g r / l i t , respectively, leads to hardness of 434 HV and thickness of 93.6 µm. A scanning electron microscope (SEM) image under optimal conditions shows that aluminum porous arrays created by an anodizing process in mixed sulfuric acid and oxalic acid electrolyte, with a hexagonal shape observed across a wide range of grain domains. [ABSTRACT FROM AUTHOR]

To address the challenges posed by the complex shapes of hollow parts, this study examined the ultrasonic-assisted granular medium hydroforming (UGMF) process for tubular components. The dynamics of the deformation behavior and deformation control during 6063-T5 aluminum alloy tube free forming by UGMF were studied via simulations and experiments. Based on the ABAQUS software platform, a coupled method based on finite element (FE) simulation analysis and discrete element (DE) analysis for the UGMF free forming process was used. The results showed that ultrasonic vibration (UV) could reduce the forming force required for expansion and promote the flow of material at the end to the forming area as well as inhibit the decrease in the wall thickness. The accuracy of the FE-DE coupled simulation model and a parabolic geometric model was verified by testing. The results found that UV enhances material flow, decreases the forming force needed, and minimizes damage to the granular surface. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present investigation examined the impact of thermal cycling applied during the painting of sheet steels and the transfer period in the forming of W-temper heat treatment of high-strength aluminum alloy on springback. The U-draw bending test was conducted numerically and experimentally to examine the springback parameters. Pre-painted steel might be aged due to surface cycling during painting and it changes the mechanical characteristics. As a result, pre-painted steel becomes more susceptible to springback. It is also observed that springback is mostly reliant on the amount of transfer time between the W-temper forming of aluminum alloy. To sum up, the interplay among material characteristics, processing techniques, and forming conditions leads to the springback phenomena. [ABSTRACT FROM AUTHOR]

Ammonia alane AlH 3 NH 3 (AA) exhibits a high gravimetric hydrogen storage capacity, with 12.86 wt% H, positioning it as a potential solid hydrogen carrier. It has nevertheless received limited attention, with only few computational studies exploring its capabilities, and it has been overshadowed by its boron analog ammonia borane BH 3 NH 3 (AB). The lower focus on AA can be attributed to its instability at temperatures above −80 °C. However, the dehydrogenation of AA has been predicted to be endothermic, and this is an attractive feature for achieving reversible hydrogen storage. AA holds thus potential as a hydrogen carrier even though its implementation is likely to pose challenges. This is the guiding principle of this article. It aims to (i) comprehensively review existing work on AA, (ii) compare the current understanding of the potential of AA as a hydrogen carrier to that of AB, (iii) address the limitations and challenges that must be overcome for effective use of AA as a solid hydrogen carrier, and (iv) discuss perspectives. [Display omitted] • Ammonia alane (AA) is a solid hydrogen carrier (12.86 wt% H 2), but understudied. • Remarkably, AA dehydrogenation has been predicted to be endothermic. • Synthesizing AA is challenging, due to its instability above −80 °C. • When heated up to 100 °C, AA polymerizes and then forms aluminum nitride. • The sequence AlH 4 NH 4 ↔AlH 3 NH 3 ↔AlH 2 NH 2 would allow reversible hydrogen uptake/release. [ABSTRACT FROM AUTHOR]

In low-power electronics, there is a substantial demand for high-performance p-type oxide thin-film transistors (TFTs) that are capable of efficient operation at low voltages. In this study, we employ anodization to form an aluminum oxide gate dielectric layer, enabling the fabrication of p-type tin oxide (SnO) TFTs that effectively operate at a low voltage of 1 V. Under optimal device fabrication conditions, the SnO TFT demonstrates an on/off current ratio exceeding 103 and a saturation mobility of 1.94 cm2 V−1 s−1 at 1 V operation. The optimal SnO TFT fabrication conditions are subsequently used to fabricate a complementary inverter, comprising a SnO TFT and an n-type indium gallium zinc oxide TFT, achieving a gain of up to 38 at a 1 V supply voltage. Notably, the inverter's switching point voltage is finely tuned to the ideal value, precisely half of the supply voltage. This oxide-based complementary inverter showcases promising potential in low-power electronics. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid T-DEA-P (Taguchi-Data Envelopment Analysis-Pareto) method to optimise and rank parameters of the electrohydraulic forming process using the aluminium (AA1100) sheets for automotive panel application. A linear programming model was formulated based on the integrated Taguchi – DEA data and solved using DEA software. The design variables are the stand-off distance, electrode gap voltage and medium. The constraints are formulated according to the levels specified in the level-factor table. Using literature data, the validation of the method was made. An important result shows that case 1 has the optimal parametric setting is SOD3E2V2M2. This is interpreted as a stand-off distance of 3mm, an electrode gap of 30mm a voltage of 260 volts and the medium as Oil with a viscosity of 0.89cP. The delta values are 16.026, 16.0605, 17.1109 and 37.3587. Delta values measure the rate of change of the average signal-to-noise ratios relative to the changes in levels. Based on the Pareto intervention, the medium is ranked first while voltage, electrode gap and stand-off distance are ranked second, third and fourth, respectively. The method aids in the planning activity for the forming process. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. One of the directions of development of plasma technologies consists in the formation of gas-metal plasma formations and throwing them to a certain distance. Known thrusters of plasma formation either have an electrode system that is prone to erosion, or a discharge system in a solid dielectric substance in which ablation occurs, or a complex gas-dynamic system with fuel supply. They do not provide acceleration of plasma formation in the atmosphere for a significant distance. Purpose. A theoretical and experimental study of electromechanical and thermophysical processes in a plasma thruster, which ensures the formation of a plasma formation due to thermal ionization by an induced current in a thin conductor layer during a high-voltage discharge on an inductor and the accelerating of a plasma formation in the atmosphere for a significant distance. Methodology. The proposed concept of a plasma thruster, in which the inductor inductively interacts with a combined armature, which includes an aluminum armature in the form of a thin (0.5-1 μm) foil, a copper armature made of a thicker foil (35-50 μm).On the basis of a mathematical model that takes into account the uneven distribution of currents in the inductor and conductive armatures, the features of the process of acceleration the combined armature in the atmosphere were established and experimental studies were carried out. Results. The electromechanical and thermal characteristics of the plasma thruster were calculated. It was established that the choice of the thickness of the dielectric layer of the armature, to which the aluminum and copper armatures are attached, is determined by the energy balance between the heating temperature of the aluminum armature and the electromechanical indicators of the thrower. Scientific novelty. It was experimentally established that the greatest density and homogeneity is observed in the middle of the plasma formation, which has the shape of a torus, moving away from the dielectric sheet on which the aluminum armature was located. As the voltage of the capacitive energy storage increases, the induced current density in the armature increases and the plasma formation becomes more uniform. Practical value. In comparison with the experimental results, the calculated current in the inductor coincides both in shape and in magnitude with an accuracy of 7 %. The biggest difference between the calculated and experimental currents of the inductor occurs when the aluminum armature is thermally destroyed. The transition of an aluminum armature into a plasma formation depends significantly on the voltage of the capacitive energy storage. References 26, figures 16. [ABSTRACT FROM AUTHOR]

The effect of process parameters on geometric dimensions is complex during belt-heated incremental sheet forming, leading to control difficulties in the geometric dimension of parts. In this study, the geometric errors were analyzed under the action of different process parameters, and the corresponding influence law was obtained through macro- and microexperiments. On this basis, the micromorphology of the deformation region section was analyzed in detail, and the effect of process parameters on micromorphology characteristics was obtained during belt-heated incremental sheet forming. Meanwhile, the dislocation density of the deformation region section was analyzed through XRD, and the change law of the dislocation density was revealed under the action of different process parameters. Therefore, the macro and micro effect mechanism of process parameters on geometric dimensions was verified, and then the control method of the geometric dimension was obtained in belt-heated incremental sheet forming. [ABSTRACT FROM AUTHOR]

Aluminum–air batteries are characterized as "green energy for the 21st century" due to their clear advantages in terms of high current discharge, high specific energy, low cost, and easy-to-obtain electrode materials. This study develops the SLM aluminum anode quality prediction model and evaluates its learning and training results using the BP neural network architecture. By altering the network topology of the SLM aluminum anode quality prediction model, we create a process parameter backpropagation model that takes advantage of the extremely adaptable capabilities of artificial neural networks. The quick and exact selection of process parameters meets the goals of density, self-corrosion current, and anode usage, hence improving the forming quality and processing efficiency of SLM aluminum anodes. The experimental results show that the process parameter backpropagation model's parameter configurations match to the real densities and self-corrosion currents, which are somewhat higher than the specified target values. The maximum error rate for the aluminum anode forming quality prediction model is 8.23%. Furthermore, the actual anode utilization rate is somewhat lower than the projected target value, indicating that the backpropagation model can satisfy actual production needs. [ABSTRACT FROM AUTHOR]

Proton-conducting polysilsesquioxane oligomers with core-shell structures consisting of hydrophilic silica-rich cores surrounded by an organic layer with sulfonic and phosphonic acid groups were synthesized. They were crosslinked by mixing with phosphoric acid and aluminum ions to form a hydrophilic Al-O-P framework. The resulting polymers were clear, uniform, flexible, and exhibited a high proton conductivity above 100 8C in non-humidified low-humidity air (B22 mS cm-1 at 120 8C and B1%RH) because of their high sulfonic acid concentration and high water retention capability. [ABSTRACT FROM AUTHOR]

This study explores the impact of different pre-temper conditions of the base metal (BM) on the microstructure and strength-ductility performance of AA7075 welded joints, aiming to identify effective processing approaches for aluminum alloy forming. The findings reveal that in comparison to the average grain size (AGS) in the weld nugget zone (NZ) of the AA7075-T6 joint (approximately 2.85 µm), the grain refinement is more pronounced in the NZ of the AA7075-O joint (approximately 2.09 µm). Concerning mechanical performance, the AA7075-T6 joint experiences softening in the welding region, demonstrating significantly lower tensile properties than the BM, with an ultimate tensile strength of 416 MPa and an elongation of 4.4 %. Conversely, the AA7075-O joint undergoes hardening in the welding region, displaying higher tensile strength than the BM, with an elongation of 8.7 %. Three-point bending destructive experiments results indicate that the AA7075-O joint can withstand larger bending angles, displaying more thorough plastic deformation and superior forming performance. [ABSTRACT FROM AUTHOR]

Aluminum alloy plates are widely used to manufacture large-scale integral structure parts in the field of aerospace. During the forming and processing of aluminum alloy plates, different degrees of residual stress are inevitably produced. Fast and accurate detection of residual stress is very essential to ensuring the quality of these plates. In this work, the longitudinal critically refracted (LCR) wave detection method based on a one-transmitter and double-receiver (OTDR) transducer and the finite element simulation were employed to obtain the residual stress. Aluminum alloy plates with different deformation amounts were fabricated by rotary forging to obtain different residual stress states. Results reveal that the plate formed by rotary forging is in a stress state of central tension and edge compression. As the deformation increases from 20% to 60%, the peak residual tensile stress increases from 156 MPa to 262 MPa, and there is no significant difference in the peak compressive stress. When the deformation reaches 60%, the difference in the residual stresses at different depths is less than 13%, which indicates that the plastic deformation zone basically penetrates the entire longitudinal cross-section of the plate. The maximum deviation between measurement and FE is 61 MPa, which means the experimental data are in good agreement with the FE results. [ABSTRACT FROM AUTHOR]

Molecular and electronic structures of transoid and cisoid forms of oxodi(fluoroboron(III)) complex of phthalocyanine [O(FB)2Pc] in the ground and excited states were studied using DFT and TD DFT methods. The peculiarities of the electrochemical and spectral properties of the tetra-tert-butyl substituted complex existing in the transoid form in organic solvents and in acid medium were considered in comparison with 1:1 complexes formed by aluminum subgroup metals and boron(III) subphthalocyanine. Coordination of two boron atoms in the coordination cavity of the phthalocyanine macrocycle leads to its tetragonal distortion both in the cisoid and especially in the transoid forms and stabilizes the frontier π-molecular orbitals, especially the lowest unoccupied MO. This results in the bathochromic shift of the long-wave Q band and strongly facilitates the reduction of macrocycle occurring for the transoid form at −0.19 V versus Ag/AgCl in dimethylformamide (DMF). Spectrophotometric titration in CH2Cl2-CF3COOH medium showed that the basicity of the meso-nitrogens is decreased upon coordination of two boron atoms. Slow deborylation can occur either in a strongly acid medium (96% H2SO4) or in the presence of water in DMF. The absence of fluorescence and ability to generate singlet oxygen is explained by quenching of the excited state due to conformation flexibility of the macrocycle and inversion of the coordination center in the transoid form. [ABSTRACT FROM AUTHOR]

Cryogenic medium pressure forming has been developed to form the complex-shaped tubular components, in which the needed shape and tube diameter directly determine the complex evolution of biaxial stress in bulging process. The superposition of biaxial stress and cryogenic temperature complicates the deformation behaviors, especially for the final fracture and bulging limit, which determine the forming quality of components. Therefore, the effects of tube geometry on failure orientation and fracture strain of Al-Mg-Si alloy tubes under cryogenic biaxial stress were elucidated, by utilizing cryogenic free bulging with different length-diameter ratios. The failure orientations and corresponding damage modes under different bulging geometric conditions were revealed. The influence mechanism of tube geometry and temperature on the failure mode was analyzed theoretically. A fracture model was established to predict the fracture strain in cryogenic bulging. The failure mode changes from circumferential cracking to axial cracking with the decreasing length-diameter ratio, owing to the stress sequence reversal induced by the significant nonlinearity of the stress path under a small length-diameter ratio. The failure mode can inverse under a larger length-diameter ratio of 1.0 at -196 °C because of the enhanced nonlinearity, which is promoted by the improved plasticity at cryogenic temperature. The established model based on the more accurate assessment of hardening ability during deformation can accurately predict the fracture strain with an average deviation of 10.6% at different temperatures. The study can guide deformation analysis and failure prediction in the cryogenic forming of aluminum alloy tubular parts. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Additive manufacturing for open-cell aluminum foam is attracting attention because the cell morphology determined by the characteristics of the aluminum foam can be accurately controlled according to the application. However, there are few reports on the additive manufacturing of closed-cell aluminum foams. Wire arc additive manufacturing (WAAM) is a low-cost additive manufacturing method and has potential for manufacturing closed-cell aluminum foams from a wire precursor. In this study, WAAM was used to produce closed-cell aluminum foam. The precursor round bar was obtained by hot-pressing a mixture of pure aluminum powder, 3 mass% TiH2 powder, and 1 mass% Al2O3 powder. After the precursor round bar with a diameter of 15mm was inserted into an A5052 aluminum alloy tube with an outer diameter of 19mm and inner diameter of 15.5 mm, the assemblage was swaged to a precursor wire measuring ϕ1.6 © 100 mm. The WAAM equipment was based on the torch of a TIG arc welding machine that moved under numerical control. Foam formation tests were carried out with the precursor wire at a torch travel speed range from 120mm/min to 620mm/min. An additive foaming test was also carried out using a precursor wire measuring ϕ1.6 © 100mm to investigate welding of the second layer to the first layer while the second layer was foaming. The density of the aluminum foam was measured by Archimedes' method to calculate the porosity. The aluminum foam samples were cut perpendicular to the long axis, and cross-sections were observed with an optical microscope. For the single-layer aluminum foam formed with a TIG arc, the maximum porosity of 60% was obtained at a travel speed of 320mm/min. A two-layer aluminum foam with a porosity of 18% and mean pore diameter of approximately 86µm was obtained in the additive experiment. The second and first layers were bonded without forming a boundary. These results indicate that closed-cell aluminum foam was successfully produced using WAAM. However, the viscosity of the base aluminum of the precursor wire must be high to obtain a high-porosity aluminum foam with WAAM. [ABSTRACT FROM AUTHOR]

CO2 reduction is appealing for the long‐term production of high‐value fuels and chemicals. Herein, using density functional theory (DFT) based calculations, we study the CO2 reduction pathway to formic acid using aluminum hydride and phosphine derivatives. Our primary focus is on aluminum hydride derivatives, aimed at improving the efficiency of the CO2 reduction process. Substituents with σ‐donating properties at the aluminum center are discovered to lower the activation barriers. We demonstrate how di‐tert‐butylphosphine oxide (LB‐O)/di‐tert‐butylphosphine sulfide (LB‐S)/di‐tert‐butylphosphanimine (LB‐N) work together with aluminum hydride to facilitate CO2 reduction process and generate in‐situ frustrated Lewis pairs (FLPs), such as FLP‐O, FLP‐S, and FLP‐N. The activation strain model (ASM) analysis reveals the significance of strain energy in determining activation barriers. EDA‐NOCV and PIO analyses elucidate the orbital interactions at the corresponding transition states. Furthermore, the study delves into the activation of various small molecules, such as dihydrogen, acetylene, ethylene, carbon dioxide, nitrous oxide, and acetonitrile, using those in‐situ generated FLPs. The study highlights the low activation barriers and emphasizes the potential for small molecule activation in this context. [ABSTRACT FROM AUTHOR]

In this study, special attention was given to the characterization of pits on the anodized aluminum alloy (Al–Zn–Mg–Cu) with an anodic aluminum oxide formed in tartaric sulfuric acid. Anodic polarization in 0.1 mol L−1 NaCl solution was used to initiate pitting corrosion in the anodized alloy. Pit characteristics, such as morphology and depth, were evaluated by using optical microscopy and optical profilometry, and scanning electron microscopy. The methodology adopted in this study revealed severe under‐film pitting due to highly occluded conditions and showed that the extent of the under‐film pitting is significantly greater than the size of pit mouth observed from the surface. [ABSTRACT FROM AUTHOR]

The male reproductive system is negatively influenced by Al exposure. Al represented a considerable hazard to men's reproduction capabilities. Amygdalin (AMG) and spirulina platensis (SP) have been considered to have a strong antioxidant and repro-protective activity; also, targeted drug delivery systems called niosomes improve the distribution of water-soluble medications like amygdalin and spirulina. Current study targeted to determine the effectiveness of AMG and SP against negative reproductive impact resulted by aluminum chloride (AlCl3) toxicity. Sixty adult male albino rats were separated into 6 groups, including the control group, which received distilled water; AlCl3 group, which received AlCl3; AMG+AlCl3 group, which received AlCl3+AMG; AMGLN+AlCl3 group, which received AlCl3+amygdalin-loaded niosomes; SP+AlCl3 group, which received AlCl3+SP; and SPLN+AlCl3 group, which received AlCl3+spirulina-loaded niosomes. All treatments were orally gavaged daily for 5 weeks, and rats were weighed weekly. At the termination of the experiment, some males (three from each group) were used for fertility traits via mating thirty virgin rat females (in a ratio of 1:2 and 2:3 male:female, respectively) followed by recording of birth weights and litter size (number of pups per each female) at birth to assess males' reproductive capability. Other males were euthanized for collection of serum, epididymal semen samples, and tissue samples for biochemical, sperm evaluation, gene expression, and histopathological measurements. There are a considerable number of negative impacts of AlCl3 on male fertility clarified by declined serum testosterone levels; an increased oxidative stress (MDA, TAC); deteriorated semen quality; down-regulation of CYP11A1, StAR, and HSD-3b gene expressions; and testicular tissue degenerative changes. In addition, litter size (number of pups per each female) and birth weights of pups obtained from mated females were affected. AMG and SP treatments, either in niosomal or conventional form, alleviated the AlCl3 negative effects by reducing oxidative stress; increasing testosterone levels; improving semen quality; upregulating of CYP11A1, StAR, and HSD-3b gene expressions; and reducing degenerative changes of testicular tissue. Besides, negative reproductive effect was diminished as observed by changes in the litter size (number of pups per each female) and birth weights of pups obtained from mated females. AMG and SP treatments (either in niosomal or conventional form), ameliorated the AlCl3 negative effects as they possess powerful antioxidant activity, as well as they have the ability to improve the reproductive activity of affected males. [ABSTRACT FROM AUTHOR]

Aqueous aluminum ion batteries (AAIBs) have drawn considerable attention due to their intrinsic safety, cost‐effectiveness, eco‐friendliness, and high theoretical capacity of aluminum. Currently, suitable anode materials are crucial for the development of high‐performance AAIBs. For the first time, a hydrophilic (ZnCr2O4) and hydrophobic (PVDF) layer modified zinc anode paired with an aluminum‐based aqueous electrolyte to construct a high‐performance aluminum–zinc hybrid ion battery. The Hydrophilic ZnCr2O4 layer of anode endows the battery with low polarization by boosting the pre‐desolvation and deposition kinetics of aluminum/zinc ions. Meanwhile, the hydrophobic PVDF layer suppresses water‐induced corrosion of the anode. The synergistic effect of the hydrophilic and hydrophobic layers of the anode stimulates the battery to exhibit unprecedented cycle life (> 6000 cycles) and considerable discharge capacity (280 mAh g−1), compared to the batteries proposed in previous works paired with aluminum alloy anodes and aluminum‐based aqueous electrolytes. This novel anode provides powerful backing for the development of long‐life and high‐capacity aqueous polyvalent ion batteries due to its low cost and simple fabrication process. [ABSTRACT FROM AUTHOR]

This investigation used aluminium, magnesium, iron ore tailings, and low-carbon steel. Iron ore tailings (5–30 wt% Mg and 50 μm in size) in an aluminium matrix formed the anode. In 0.5 M NaCl solution, the weight loss, corrosion rate, and electrochemical properties were measured. Samples A to E have corrosion rates of 0.43, 0.28, 0.36, 0.08, and 0.11 mm/yr, respectively. SEM/EDS examination revealed the presence of elemental Al, Mg, O, and Si in the anode. The XRD patterns indicate intermetallic compounds such as iron nitride (Fe3N), aluminium silver (Ag-Al), and manganese zirconium (Mn2Zr). In samples A, B, and C, Al and Mg formed a protective coating on the anode, while C and Si reduced passivation and released electrons to protect the steel. IOTs and Mg in the aluminium matrix improve the anodic corrosion resistance. The observed improvements in corrosion resistance highlight the potential of these sacrificial anodes for practical applications in corrosion protection systems. [ABSTRACT FROM AUTHOR]

Lap joining of an aluminum AA6082-T6 plate and a UHSS steel plate coated with an Al-Si layer was performed using Probeless Friction Stir Spot Welding (P-FSSW). The dwell time and rotational speed were controlled in the range of 10–15 s and 1000–1500 rpm, respectively. For all the samples, thermo-mechanical deformation occurred solely within the upper AA6082 plate. A refined grain structure was formed in the aluminum plate close to the surface. The dwell time was responsible for the intensity of the material flow, resulting in stirring between the Al-Si layer and the aluminum plate at 15 s. The microhardness distribution corresponded to the microstructure features. [ABSTRACT FROM AUTHOR]

Aluminum alloy 6082-T6 is an important material for manufacturing the outer skin of high-speed trains, and laser shock forming can realize the rapid forming of complex-shaped plates. In order to improve the efficiency of the simulation modeling of laser shock forming for aluminum alloy 6082-T6, Python scripting language was used for the secondary development of Abaqus. A plugin was utilized to simulate and analyze the laser shock forming process of aluminum alloy 6082-T6. The coordinates of the plate after laser impact molding were measured using a coordinate measuring machine to calculate the arc bow height of the plate. The accuracy of the simulation model was verified by comparing with the simulation results. The deformation characteristics of plastic strain and arc height of aluminum alloy 6082-T6 under different laser process parameters were analyzed. The simulation plugin has a concise interface, high operability, and accurate results with the other parameters unchanged. When the laser energy is 5 J, 6 J, and 7 J, the corresponding arc heights are 5.9 mm, 6.6 mm, and 7.2 mm, respectively. As the thickness of the sheet increases, the deformation changes from concave at 1 mm to convex at 2 mm, 3 mm, 4 mm, and 5 mm. As the spot size increases from 1 mm to 5 mm, the transmission mode of the shock wave gradually changes from spherical wave to planar wave, and the arc height of the sheet increases from 4.6 mm to 8.2 mm. With the increase in the spot overlap rate, the impact area accumulates residual stress, and the arc height of the sheet is 5.7 mm, 6.6 mm, 7.3 mm, and 8.5 mm, respectively. The secondary development of ABAQUS 2021 using Python 3.6 scripting language has improved the efficiency of simulation modeling and provided reference for rapidly predicting the deformation characteristics of aluminum alloy 6082-T6 under different laser process parameters. [ABSTRACT FROM AUTHOR]

Currently, 1060 aluminum alloy is widely applied in the electronics industry, construction, the aerospace field, traffic engineering, decorations, and the consumer goods market for its good chemical, physical, and mechanical properties. In general, excellent processing property is necessary and important for the manufacturing of complicated panels. In this paper, a special 2D ultrasonic vibration incremental forming method is designed to improve its plasticity and mechanical properties. Three kind of processing methods, including traditional single-point incremental forming, longitudinal ultrasonic vibration incremental forming, and 2D ultrasonic vibration incremental forming, are used for the flexible manufacturing of cones and cylindrical cups of 1060 aluminum alloy sheet. Then, micro-hardness tests, residual stress tests, and scanning electron microscopy tests are carried out to probe the changes in micro-structure and mechanical properties and to analyze the effects of different types of ultrasonic vibration on the plasticity and fracture characteristic of 1060 aluminum alloy. It is proven that 2D ultrasonic vibration facilitates the improvement of plasticity and surface qualities of 1060 aluminum alloy better than the other two processing methods. Therefore, the novel 2D ultrasonic vibration incremental forming process possesses substantial application value for the flexible and rapid manufacturing of complicated thin-walled component of aluminum alloy. [ABSTRACT FROM AUTHOR]

Effective charge carrier‐selective contacts are a crucial component of high‐performance crystalline silicon (c‐Si) solar cells. Organic materials deposited via self‐assembly on the c‐Si surface are promising candidates for simplified, scalable, and cost‐effective processing of charge extraction layers. This study investigates the application of nPACz self‐assembled monolayers (SAMs), based on carbazole and phosphonic acid groups, where n (= 2, 4, or 6) is the aliphatic chain length, to facilitate electron extraction in c‐Si solar cells by tuning the work function of aluminum (Al) at the rear contact. So far, these SAM molecules are mainly applied as the hole‐selective layer in state‐of‐the‐art perovskite and organic solar cells, via anchoring on a metal oxide electrode. Here, by inserting 2PACz between amorphous silicon passivated c‐Si and Al, an electron‐selective contact with a contact resistivity of 65 mΩ cm2 is achieved and a power conversion efficiency of 21.4% with an open‐circuit voltage of 725 mV and a fill factor of 79.2% is demonstrated. Although the 2PACz displays some instability in this study, its initial performance is comparable to those achieved with conventionally used n‐type amorphous silicon. This study highlights the potential of solution‐processable organic SAMs in forming carrier‐selective contacts for c‐Si heterojunction solar cells. [ABSTRACT FROM AUTHOR]

Broad use of lightweight aluminium alloy parts in automobile manufacturing, aerospace, electronic communication, and rail transit is mainly formed through deep drawing process. Deep drawing friction is a key boundary condition for controlling the forming quality of aluminium alloy parts. However, due to the oxidation and adhesion tendency of aluminium alloys, the tribological situations of aluminium alloy deep drawing (AADD) system is more complicated than those of traditional deep drawing of steel sheets. Therefore, the study of AADD friction is essential for manufacturing high-performance aluminium alloy parts. Herein, aiming to provide a valuable reference for researchers in related fields, a comprehensive review of AADD friction is provided, including friction mechanism, influencing factors, friction measurement, friction model, friction simulation, and lubrication-free friction control. Finally, a brief conclusion and several current challenges were discussed. [ABSTRACT FROM AUTHOR]

Al-Cu-Fe-Ce quasicrystalline-reinforced 6061 aluminum matrix composites were prepared through hot press sintering and treated with a solid solution and aging treatments. The influence of the solid solution and aging treatments on the microstructure and mechanical properties of the composites was investigated by XRD, EDS, SEM, and TEM. The results show that using Al-Cu-Fe-Ce quasicrystalline intermediate alloy as the reinforcing phase increases the interfacial areas of the composites and enhances the grain boundary strengthening effect, which is conducive to the improvement of the mechanical properties of the composites. And through the solid solution and aging treatment, the β phase and the Al2CuMg phase belonging to the orthorhombic crystal system, as well as the β″ phase and a small amount of the β′ precipitated phase, were formed in aluminum matrix composites, and these precipitated phases all existed in the composites in a fine and uniform distribution, which ensured the consistency of the mechanical properties of the materials and improved the mechanical properties of the composites. Meanwhile, the deficiency of quasicrystalline particle-reinforced 6061 aluminum matrix composites in age-hardening was solved and the age-hardening capability of the composites was further developed. This method provides a feasible process route for the preparation of high-performance aluminum matrix composites. The application of this process is expected to improve the mechanical properties and durability of this composite and offer a more reliable option for the application of aluminum matrix composites in aerospace, transportation, and other fields. [ABSTRACT FROM AUTHOR]

Hybrid foams are a type of composite material created by combining two foam materials. They are preferred in many applications due to their lightweight, high strength, and ability to absorb more energy. In this research, a new hybrid foam was designed for use in sandwich cores of structural materials. The hybrid foam was formed by combining closed-cell aluminum foam and expanded polystyrene (EPS)-filled syntactic foam. The EPS-filled syntactic foams were produced with the conventional mold casting technique. Uniaxial compressive behaviors (0.5 mm/min) of layered hybrid foams consisting of EPS-filled syntactic foam with three different densities and closed-cell aluminum foam were investigated experimentally and compared with conventional single-foamed materials. These results exhibited that in general, layered hybrid foams outperform conventional single-foamed materials in terms of compressive strength. Moreover, the natural frequency and damping ratio of the layered hybrid foams were investigated by vibration tests under clamped-free and free-free boundary conditions and compared to conventional single-foamed materials. It was established that the vibration damping capacity of the layered hybrid foams improved compared to the closed-cell aluminum foam. Additionally, the microstructure of the conventional single-foamed materials was examined by SEM. In the outcome of the research, the experimental results showed that layered hybrid foam provides an opportunity to design lightweight cellular materials with effective mechanical properties. [ABSTRACT FROM AUTHOR]

The study examined the composition and forms of iron and aluminium oxides in benchmark soils of central southwestern Nigeria. Soils developed from distinct parent rock types, including coarse-grained granite and gneiss, fine grained biotite gneiss and schist, and the amphibolite complex which correspond to the parent rocks of the soils of Iwo (Typic Paleustults), Egbeda (Rhodic Kandiustults) and Itagunmodi (Typic Haplustults) Associations, respectively, were selected for the study. Notably, these soils collectively encompass approximately 60% of the total land area in central southwestern Nigeria. The less than 2 mm soil fractions were pre-treated with hydrogen peroxide to remove soil organic matter. Thereafter, oxides of Fe and Al were extracted using three different extractants: dithionite-citrate-bicarbonate (DCB) mixtures, acidified ammonium oxalate and sodium pyrophosphate solution. The quantification of Fe and Al oxides contents in the respective extracts were carried out using Inductively Coupled Plasma—Atomic Emission Spectrometry. The research findings indicated that the DCB extractable forms of Fe and Al oxides were more abundant compared to other forms of these oxides, and a substantial portion of these oxides within the soils existed in crystalline form. Among the soil series studied, Itagunmodi series exhibited the highest amount of DCB- and oxalate extractable Fe oxides, while Iwo series had the highest content of Fe and Al oxides extracted by sodium pyrophosphate solution. Importantly, the presence of Fe oxides were found to negatively impact the reactivity of SOM in the soils. [ABSTRACT FROM AUTHOR]

The heterogeneous structure of polymer and aluminum alloy is an effective way to meet the dual technical indicators of structural performance and lightweight design. Friction stir welding (FSW) is a solid-phase welding technology characterized by low temperature and large plastic deformation. It is basically not affected by the crystal structure and physical-chemical properties of materials and can realize polymer and aluminum alloy-specific materials quality connection. This paper presents a comprehensive review of the current advancements in FSW between polymers and aluminum alloys with a focus on optimizing welding parameters, joint formation, defect identification, and mitigation. The results showed that the most important details are that high rotation speed combined with low welding speed that is beneficial to increase welding heat input, improve joint forming and mechanical properties, and form aluminum riveting structure. Welding defects are the main reason for the low FSW performance of polymer and aluminum alloy heterogeneous structures. To improve the forming and load-bearing capacity of heterogeneous structures, welding tool structure design, surface pretreatment, and welding structure optimization can be utilized. [ABSTRACT FROM AUTHOR]

The characteristics of concentrator photovoltaic modules based on a 120 × 120 mm Fresnel lens with secondary concentrators in the form of hollow aluminum focons with internal mirror walls are studied. The optimal sizes and configurations of secondary concentrators are determined to increase the efficiency of focusing systems of concentrator modules. The maximum value of the allowable misorientation angle was obtained, equal to ±0.75°, corresponding to a power drop to a level of 90% relative to the maximum power value of the concentrator photovoltaic module at normal beam incidence. For a module with the most efficient focon 40 mm high and side face slope angles of 17°, the maximum efficiency of the module under laboratory conditions was obtained, equal to 35.15%. Under natural conditions, the efficiency value reached 33.8%. The results obtained correspond to the level achieved for the best foreign analogues. [ABSTRACT FROM AUTHOR]

The compatibility of the wrought Al-Ca alloy with the element Fe was investigated in the present study. In this work, both the Al-Ca alloy and Al-Ca-Fe alloy were synthesized through melting, casting, heat treatment, and rolling. A new ternary Al-Ca-Fe eutectic phase, identified as Al10CaFe2 with an orthorhombic structure, demonstrated enhanced performance, as revealed by nanoindentation tests. Combining the results of the nanoindentation and EBSD, it can be inferred that during the rolling and heat treatment process, the divorced eutectic phases were broken and spheroidized, and the structure of the Fe-rich alloy became finer, which promotes the formation of fine grains during the process of dynamic recrystallization and effectively hindered the grain growth during thermal treatment. Consequently, the strength of the as-rolled Al-Ca alloy was improved with the addition of 1 wt.% Fe while the ductility of the alloy was maintained. Therefore, adding Ca into the high-Fe content recycled aluminum altered the form of the Fe-containing phases in the alloy, effectively expanding the application scope of recycled aluminum alloy manufacturing. This approach also offered a method for strengthening the Al-Ca aluminum alloys. Compared to the traditional approach of reducing Fe content in alloys through metallurgical means, this study opened a new avenue for designing novel, renewable aluminum alloys highly compatible with impurity iron in scrap. [ABSTRACT FROM AUTHOR]

In advanced solid-state manufacturing processes such as friction stir welding, the metal's temperature ranges from room temperature to the solidus temperature. The material strength in the temperature range is generally required for investigating the mechanical behaviors. In this communication paper, an analytical model is proposed for describing the thermal softening of aluminum alloys for room temperature to solidus temperature, in which the concept of temperature-dependent transition between two thermal softening regimes is implemented. It is demonstrated that the proposed model compares favorably to the well-known Sellars–Tegart model and Johnson–Cook model. The constants of the proposed model for nine typical engineering commercial aluminum alloys are documented. [ABSTRACT FROM AUTHOR]

The reaction of alkaline solution and metallic aluminum present in municipal solid waste (MSW) incineration bottom ash (IBA) generates hydrogen gas. Thus, it is crucial to characterize the metallic aluminum in IBA for its safe utilization and proper disposal. However, the inherent inhomogeneity of IBA, random distribution of metallic aluminum in IBA grains, presence of aluminum in compound forms, and lack of reliable quantitative characterization techniques pose significant challenges to the holistic understanding of metallic aluminum in IBA. This research aims to address these questions systematically and present a comprehensive understanding of metallic aluminum in IBA. A classification strategy based on mineralogical and particle size basis is adopted to minimize the inhomogeneity of IBA. Furthermore, the spatial distribution of metallic aluminum in IBA is studied through SEM/EDS of the IBA grains cross-sections of different particle sizes and mineralogical classes. Subsequently, a modified in-house designed collecting gas over liquid setup was developed for an easy and reliable quantitative characterization. The metallic aluminum content was the highest for 0.3–1.18 mm and lowest for < 0.3 mm range, and within a given mineralogical class, the metallic aluminum content decreases with decrease in particle sizes. The microanalysis of cross-sections of IBA grains showed that the aluminum is present as aluminum alloy formed during incineration or in oxide form, majorly in fine fractions (< 0.3 mm). The current study seeks to provide a complete picture of metallic aluminum distribution in IBA. [ABSTRACT FROM AUTHOR]

Shot peen forming is a process widely used to shape aircraft components such as wing skins, yet its fundamental working is still crudely understood. It is understood that a light conventional peen forming treatment applied uniformly over an initially flat plate will induce isotropic in‐plane stretching of the surface layer and will thus lead to a panel curving with identical curvatures in all directions. However, [1] made the startling observation that uniformly peen formed aluminium plates of different aspect ratios all bent along their laminating direction irrespective of the peening direction. This experimental result is counterintuitive because the residual stresses due to the lamination process are 1 order to 2 orders of magnitude smaller than those induced by the shot peen forming treatment. In the present study, we apply the eigenstrain theory to estimate the effect of the different sources of anisotropy on uniformly peen formed aluminium plates. Potential sources of anisotropy included the plastic anisotropy of rolled aluminium, nonequibiaxial initial stresses that redistribute when their equilibrium is disturbed by peening, the geometry of the specimens and externally applied prestress. For the alloy and peening conditions considered, we show that plastic anisotropy had no discernible influence on the resulting shape of the peen formed specimens. Initial residual stresses, on the other hand, caused slightly larger bending loads in the rolling direction of the alloy. Although the magnitude of these loads was approximately 30 times smaller than peening‐induced loads, it was sufficient to overcome the geometric preference for rectangular sheets to bend along their long side and cause all unconstrained specimens to bend along the rolling direction instead. Our analysis highlights the importance of the history of the material that is being peened. Residual stresses already present in the part before peening must be considered to ensure good simulation predictions. [ABSTRACT FROM AUTHOR]

The present study employed the ABAQUS numerical simulation method to analyze the forward flow forming of 7075 aluminum alloy tubes using power staggered spinning compression materials. Subsequently, a power staggered spinning experiment was conducted to analyze the microstructure and mechanical properties. The simulation results revealed that increasing the spinning temperature led to a decrease in the limit thickness reduction per pass while increasing range, as well as enhanced deformation along the wall thickness direction. At 400 ℃, favorable forming properties were observed with minimal plastic strain occurring in the inner layer when thickness reduction is below 10%. These findings indicate that an escalation in total thickness reduction resulted in refined and uniform grain distribution along the wall thickness direction, accompanied by improved hardness (up to 178.6 HV) due to synergistic effects from fine grain strengthening, strain strengthening, and dispersion strengthening induced by second particles. [ABSTRACT FROM AUTHOR]

The interaction of a titanium carbide nanoparticle with aluminum (100), (110), and (111) substrates is investigated within the density functional theory. The nanoparticle–substrate interaction energies are determined; the electron density distribution and the electron localization function between aluminum, titanium, and carbon atoms are analyzed. It has been established that the atoms in the upper layers of the aluminum (100) and (110) substrates are significantly displaced relative to their initial positions as a result of the interaction with the nanoparticle, whereas a minor displacement of atoms is typical for the (111) substrate. The interaction between aluminum and carbon atoms at the Al–TiC interface is due to the formation of covalent Al–C chemical bonds. The aluminum atoms forming carbide bonds do not form chemical bonds with titanium atoms. The aluminum atoms that are adjacent to the titanium atoms and are not involved in the formation of carbide bonds form metallic Al–Ti bonds. [ABSTRACT FROM AUTHOR]

In the present study, waste aluminum dross was used as reinforcement in the development of an aluminum-based composite. Waste aluminum dross in the form of a mixture of Al and Al2O3 was collected from aluminum industries. Microwave sintering technique was employed for the processing of composite material. The composite was developed with the constant 5 wt. % of aluminum dross powder. Maximum hardness, compressive strength, and tensile strength were found for the composition Al-5 wt. % aluminum dross powder—5 wt. % graphene composite. However, minimum porosity was found for the composition Al-5 wt. % aluminum dross powder—5 wt. % graphene composite. Uniform distribution of the reinforcement particles was observed for the composition Al-5 wt. % aluminum dross powder—5 wt. % graphene composite. XRD of the Al/aluminum dross powder/graphene composite showed the presence of Al, Al2O3, and Al4C3 phases. The fracture surface of the Al-5 wt. % aluminum dross powder—5 wt. % graphene composite was composed of a dendrite structure with micro-porosities. Dimples were also not observed from the tensile fracture surface morphology of Al-5 wt. % aluminum dross powder—5 wt. % graphene composite. [ABSTRACT FROM AUTHOR]