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Traditional aluminum alloys have a mature industrial system, but their properties are still constrained by factors such as precipitation behavior, the grain boundary state, solidification defects, and residual impurities. This paper systematically reviews the microstructure formation, strengthening mechanisms, and performance regulation laws for major wrought and casting aluminum alloys. It also compares the characteristics of different alloy systems in terms of strength, ductility, corrosion resistance, fatigue performance, and manufacturing stability. The analysis shows that the development focus for traditional aluminum alloys has shifted from single performance improvement to multi-performance balance and precise control of the microstructure. With the increase in the proportion of recycled raw materials, the importance of impurity tolerance and the controllable transformation of second phases has further increased. At the same time, CALPHAD, physical models, and data-driven methods provide new means for alloy composition and process optimization, but their effectiveness still needs to be verified in actual components and engineering conditions. This paper can provide a reference for microstructure design, material selection, and performance optimization for the circular manufacturing of traditional aluminum alloys. Full article

In this paper, we experimentally investigated the integrated processing of high-iron Kazakh bauxites by reducing smelting of ore–coke–lime briquettes to produce an Fe-Al-Si metallic alloy, which is of potential interest for steel deoxidation, together with calcium-aluminate slag, which is of potential interest for alumina extraction. Briquettes containing bauxite, metallurgical coke (10–20 wt.%), and freshly calcined lime (10 wt.%, constant) were melted in a muffle furnace at a temperature of 1200–1450 °C. Complete separation of metal and slag was achieved at 1400–1450 °C, whereas at 1200–1350 °C, separation remained incomplete. Changing the coke/bauxite mass ratio in the charge from 0.125 to 0.286 increased the total content of metallic Si, Al and Fe in the recovered metallic product from 77.1 to 98.66 wt.%, according to X-ray fluorescence (XRF) analysis after two-stage magnetic separation; the metallic product obtained with a coke/bauxite ratio of 0.286 in the charge contained 72.8% Fe, 23% Al and 2.86% Si (with minor impurities of Ti, Mn and Cr), while the associated slag was represented mainly by CaO (59.5%) and Al2O3 (34.0%). These slag characteristics indicate its potential suitability for alumina extraction or as a filler for structural concrete. The proposed route represents a potentially low-waste alternative for processing high-iron bauxites that are poorly suited to the classical Bayer process, avoiding the direct formation of red mud and supporting Kazakhstan’s transition toward closed-loop bauxite processing. Full article

Fused silica–aluminum alloy dissimilar connections are in urgent demand in fields such as aerospace optoelectronic packaging, vacuum optical windows, and micro-electro-mechanical systems, yet the dramatic mismatch in thermal-expansion coefficient and thermophysical properties between the two materials has long been a bottleneck for reliable joining. Current ultrafast laser welding of such heterogeneous systems still suffers from prominent problems, including stringent optical contact requirements, high crack sensitivity on the fused silica side, and unclear coupling mechanism between clamping conditions and joint defects. This work systematically studies the joining process of femtosecond laser welding of fused silica and 6061 aluminum alloy dissimilar materials, focusing on the effects of scanning speed, pulse energy, scanning spacing, and fixture preload on the shear strength, microstructure, and elemental diffusion behavior of the joints. The results confirm that scanning speed and scanning spacing have a synergistic effect on heat input density; the magnitude of the fixture preload is a key factor determining the interfacial residual stress and crack sensitivity. By optimizing the scanning speed (6 mm/s) and combining it with a low preload and 140 μm scanning spacing, a high-strength heterogeneous joint with uniform elemental transition and no macroscopic cracks can be obtained. This study provides a detailed process-optimization approach for high-quality laser welding of dissimilar brittle/ductile materials. Full article

Fe/Cr substitution in α-Al₁₂(Fe,Cr)₃Si₂-type intermetallic particles was investigated using first-principles calculations combined with the Debye–Grüneisen model over 0–850 K at zero external pressure. To examine Fe/Cr mixing within the α framework, 238-atom hP238 cells were modeled at x_Cr = 0, 0.239, 0.500, 0.739, and 1.000. At 0 K, static mixing enthalpy was negative at x_Cr = 0.239 and 0.500 but became slightly positive at the highest sampled intermediate Cr fraction, x_Cr = 0.739. The x_Cr = 1.000 model served only as a hypothetical hP238 endpoint. At a homogenization temperature of 813 K, configurational entropy favored Fe/Cr mixing, while the vibrational contribution was positive and partly offset this effect. The resulting mixing free energies were −11.0 and −6.0 meV/atom for x_Cr = 0.239 and 0.500, respectively, and +7.6 meV/atom for x_Cr = 0.739. The results show that low-to-intermediate Cr substitution, including near-equiatomic Fe/Cr occupancy, is thermodynamically favorable within the α framework, whereas the sampled Cr-rich intermediate composition is unfavorable relative to the two modeled hP238 end members. Full article

This paper presents a preliminary safety assessment of the liquid deuterium premoderator container developed for the AlSUN ultra-cold neutron source, integrated into the thermal column of the WWR-K reactor. Analytical calculations were conducted to evaluate the container’s response under three categories of hypothetical accident scenarios: (1) reactor power control and cryostat cooling failures, (2) breaches in the vacuum insulation, and (3) a stoichiometric deuterium–air detonation as a beyond-design-basis residual-risk bound. Key thermodynamic parameters—including temperature and pressure evolution—were tracked in each scenario to characterize the transient system behavior. The resulting profiles were then used to estimate mechanical stresses on the container walls, considering the thermomechanical properties of the materials used in its construction. Special attention was given to the structural integrity of Aluminum Alloy 5056, assessing its performance under extreme thermal and mechanical loads. These findings support the selection of Aluminum Alloy 5056 and inform future, more comprehensive studies employing advanced simulation tools. Full article

Electrified mobility regulations and lifecycle emissions targets have increased the demand for lightweight structural materials in vehicle architectures. Bioinspired composite materials offer microstructural configurations that alter conventional trade-offs among specific stiffness, crash energy absorption, and manufacturing energy requirements. This review evaluates the translation of biological structural archetypes including nacre, bamboo, cortical bone, and lotus leaves into load-bearing and functional automotive components. Quantitative benchmarks of continuous natural-fiber laminates, bio-cellular lattices, and mycelium-based acoustic cores are compared against high-strength steel and aluminum alloys. Key mechanical and functional metrics, including specific energy absorption (ranging from 35 to 48 kJ kg⁻¹ for bioinspired crash structures), dynamic loss factors, and Cassie-Baxter superhydrophobic surface stability, are evaluated alongside high-throughput manufacturing routes such as high-pressure resin transfer molding (HP-RTM) and additive manufacturing. Methodological parameters for ISO 14040/14044-compliant Life Cycle Assessment (LCA) are synthesized, emphasizing component-level functional units over gravimetric mass equivalence. Furthermore, operational boundaries, specifically hygrothermal interfacial degradation, matrix glass transitions (T_g < 120 °C), and multi-axial loading sensitivity, are systematically outlined to define design limits for automotive deployment. Full article

Conventional design paradigms for vehicle underbody armor face an inherent trade-off: enhancing blast protection invariably incurs a prohibitive weight penalty. Here, we investigate a mechanical pre-stressing strategy for high-strength steel V-shaped vehicle underbody structures. A conventional V-shaped baseline structure was first subjected to a 6 kg TNT blast test, and the measured response was used to validate the numerical model. Based on the validated numerical model, four mass-equivalent (100 kg) configurations were subsequently compared numerically under escalating threats (2~8 kg TNT): pre-stressed steel, homogeneous steel, and all-metallic honeycomb sandwich panels (comprising high-strength steel face sheets and an aluminum alloy core) with both positive and negative Poisson’s ratios. The numerical results predict that the pre-stressed steel configuration exhibits the smallest maximum permanent floor deformations among the four configurations, with values of 22 mm, 46 mm, 131 mm, and 208 mm under 2, 4, 6, and 8 kg loads, respectively. Mechanistically, we reveal that for V-shaped geometries, residual-stress-induced stiffening and geometric arching are profoundly more effective than core crushing in controlling global bending, while the auxetic steel-faced aluminum honeycomb offers only marginal improvements over its conventional counterpart. This study offers a potential pathway for overcoming the weight–protection trade-off in underbody armor design. While the numerical predictions are encouraging, direct experimental validation of the pre-stressed configuration remains necessary prior to practical application. Full article

Aluminum alloys used in aircraft structures are susceptible to corrosion fatigue cracking under combined aggressive environments and cyclic loading, threatening structural integrity. Pure data-driven models often fail under distribution shifts, while single-physics-informed neural networks (PINNs) lack flexibility in complex conditions. This paper proposes a dual-physics-informed neural network (DPINN) that integrates Walker and Forman crack growth models into a deep residual network. The model adaptively fuses both physical formulas via a trainable weight α and predicts material constants. A hybrid loss function with α regularization ensures physically consistent predictions. Using comprehensive corrosion fatigue data covering eight aluminum alloys, we evaluate the model on an internal test set and, more importantly, on an independent external test set simulating real-world distribution shifts. We further investigate an incremental learning scenario where the model is sequentially fine-tuned with increasing fractions of the external set. Results demonstrate that DPINN rapidly rectifies initial distribution mismatch, crossing the engineering reliability threshold (R² > 0.90) at an early incremental stage, and achieves superior performance after fine-tuning, significantly outperforming both a single Walker-PINN and gradient boosting regressors. SHAP feature importance analysis identifies ΔK and stress ratio as dominant drivers, confirming mechanistic consistency. The proposed architecture offers a data-efficient and interpretable tool for corrosion fatigue crack growth prediction in aluminum alloy structures. Full article

In this study, an Al–20 wt.% Mg alloy was synthesized to systematically correlate its electrochemical behavior in synthetic seawater with the microstructural evolution induced by heat treatment at 190, 300, and 350 °C for 6 h. The samples characterized by SEM and XRD reveal a progressive morphological evolution of the β–Al₃Mg₂ intermetallic phase. The open circuit potential, the potentiodynamic polarization and the electrochemical impedance spectroscopy showed that this microstructural evolution increased the microgalvanic corrosion, promoting passive-film breakdown, and reducing charge-transfer resistance. The Al–20 wt.% Mg alloy treated at 350 °C exhibited the highest corrosion current density, associated with β–Al₃Mg₂. These results demonstrated that controlling beta-phase precipitation through heat treatment provides an effective approach to tune the electrochemical behavior of high-magnesium aluminum alloys. Full article

Metal-cutting operations can generate resource losses not only through the kerf itself but also through subsequent reworking, removal of altered edge material, and processing of workpieces that later prove unsuitable. This study develops and experimentally evaluates an automated eddy-current inspection system intended to characterize metal edges immediately after cutting. The system combines a miniature high-frequency eddy-current transducer, three-axis positioning, digital signal acquisition, and software-based processing. A clad D16AT aluminum alloy specimen with edges produced by laser cutting, cold sawing, and hot shearing was scanned. The air-to-metal transition profiles were described by a logistic function, yielding an electromagnetic transition coordinate xc, a transition parameter s, and the coefficient of determination R². The fitted xc values were 7.30, 8.76, and 8.93 mm for cold-sawn, laser-cut, and hot-sheared edges, respectively; s was 0.64, 0.59, and 0.67 mm, while R² was 0.961, 0.959, and 0.941. These quantities are interpreted as comparative electromagnetic descriptors and not as direct measurements of heat-affected-zone depth or defect probability. A scenario calculation based on the displacement of the electromagnetic transition relative to the geometric edge gave apparent material-removal indices of 0.192, 1.127, and 1.236 g per 40-mm edge. Under this explicitly model-based scenario, the laser-cut edge was 8.8% lower than the hot-sheared edge. Complementary measurements showed concordant ordering of the electromagnetic descriptors with roughness, burr height, HV0.1, altered-zone depth, conductivity, and removed-layer mass; the apparent and measured masses differed by 0.3–1.1% for this specimen. The results demonstrate that automated eddy-current mapping can differentiate edge states and provide structured data for routing decisions in resource-efficient and zero-defect manufacturing. Independent-specimen replication, fully traceable physical characterization, and production-scale validation are required before the descriptors can be used as acceptance thresholds or as direct estimates of actual waste. Full article

The coarse Fe-containing intermetallics (IMCs) induced by excessive Fe levels seriously degrade the mechanical and corrosion properties of recycled aluminum alloys. Controlling the nucleation and growth behavior has been confirmed as effective in refining the Fe-containing intermetallics (IMCs) and enhancing the ductility of recycled aluminum alloys. In this work, the modification mechanism of Al–Ti–B in Al–2Fe alloy was systematically investigated by combining SEM microstructure, TEM characterization and DFT calculations. TEM observations reveal that TiB₂ particles are preferentially embedded within Al₁₃Fe₄ phases, forming coherent or semi-coherent interfaces, which act as nucleation sites and facilitate the refinement and uniform distribution of Fe-containing IMCs. Interface property calculation results show that the Al₁₃Fe₄ (620)/TiB₂ (01$\stackrel{\mathrm{-}}{1}$1) interface exhibits lower lattice mismatch (4.4%) and interface energy, indicating stronger interfacial bonding and higher interface stability. The electronic structure results showed that the enhanced interface stability is attribute to the pronounced charge redistribution. Stable interface structure reduces the heterogeneous nucleation barrier and promotes refinement efficiency of Fe-containing ICMs. This study provides theoretical guidance for the refinement of Fe-containing impurity phases and high-performance sustainable recycling of aluminum alloy scrap. Full article

Joining dissimilar lightweight metals, such as magnesium (Mg) and titanium (Ti), presents critical challenges due to their differing physical properties and limited mutual solubility. This research explores the potential of laser impact welding (LIW) to overcome these barriers by investigating the effects of aluminum (Al) content in Mg-Al alloys, interlayer integration, and the formation of intermetallic phases at the bond interface. Emphasis is placed on understanding how variations in Al composition and the inclusion of an Al interlayer influence the bonding mechanisms between Mg and Ti. Through detailed microstructural analysis and phase identification, this study characterizes the intermetallic phases present at the weld interface, examining their size, distribution, and location. The presence of an Al interlayer was found to significantly improve bonding success, promoting favorable interface morphology and minimizing detrimental intermetallic formation. These findings provide key insights into the underlying mechanisms enabling successful LIW of dissimilar lightweight metals and offer valuable guidance for industrial applications seeking to advance joining strategies in high-performance alloy systems. Full article

Friction stir welding (FSW) is a solid-state joining process widely used for aluminum alloys due to its low heat input, reduced distortion, and ability to produce high-quality joints. However, excessive tool forces generated during the welding process can increase machine loading, accelerate tool wear, and negatively affect the process efficiency. Therefore, understanding the relationship between welding parameters, tool forces, and the joint performance is essential for achieving high-quality welds while avoiding unnecessary mechanical loads. In this study, 4 mm thick AA5754 aluminum alloy plates were joined using the FSW process, and the feasibility of using tool force measurements for process optimization was investigated. A comprehensive experimental matrix consisting of nine different rotational speeds and ten different tool travel speeds was established based on preliminary studies and previous literature. During each welding operation, forces acting on the tool in the F_x, F_y, and F_z directions were continuously recorded. The welded joints were evaluated through tensile testing (Zwick Z300 universal testing machine, ZwickRoell, Ulm, Germany), hardness measurements, and microstructural characterization using scanning electron microscopy (SEM) (ZEISS Merlin scanning electron microscope, Carl Zeiss Microscopy GmbH, Oberkochen, Jena, and Göttingen, Germany). A Pearson correlation analysis and a two-way analysis of variance (ANOVA) were performed at a 95% confidence level to quantify the relationships and statistical significance of the process parameters. The results showed that F_z was the dominant force component during welding. The rotational speed had a statistically significant effect on the tensile strength, yield strength and hardness (p < 0.05), accounting for 99.39% of the total variation in hardness. For the mean tool force, both the rotational speed and the tool travel speed were statistically significant (p < 0.0001), contributing 38.48% and 47.16% of the total variation, respectively. The rotational speed also accounted for 81.55% of the variation in the maximum axial force. The Pearson correlation analysis showed a strong negative correlation between the rotational speed and hardness (r = −0.73), whereas the tool travel speed showed positive correlations with F_x (r = 0.61), F_z (r = 0.62), and the mean tool force (r = 0.68). Despite the increased tool loading associated with higher travel speeds, no corresponding improvement in the mechanical performance was observed. The results demonstrated that appropriately selected welding conditions produced joints with a yield strength and hardness exceeding 90% of the corresponding base material properties while maintaining relatively lower tool forces. SEM observations confirmed grain refinement in the stir zone. Overall, the combined correlation and ANOVA results demonstrate that real-time tool force monitoring can provide a quantitative basis for selecting FSW parameters that achieve an adequate mechanical performance while minimizing unnecessary machine and tool loading. Full article

7xxx series aluminum alloys exhibit high strength and low density; however, their high degree of alloying results in a pronounced hot-cracking tendency, making direct casting forming challenging. In this study, a rheo-squeeze-cast AA7075 alloy was investigated. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and room-temperature tensile testing were employed to systematically examine the effects of the solution treatment window on the microstructure and mechanical properties of the castings. The distinctive contribution of this work is the quantitative correlation of solution-time-dependent second-phase evolution and porosity with the tensile behavior of ECSC-assisted rheo-squeeze-cast AA7075. The results show that, with increasing solution treatment time, the intergranular eutectic phases gradually dissolved, and their morphology evolved from lamellar structures into fine rod-like features. When the solution treatment time was extended to 12 h, a small number of pore defects appeared in the microstructure. Under the conditions of solution treatment at 470 °C for 8 h followed by aging at 120 °C for 24 h, uniformly distributed Zn–Mg-rich aging precipitates were observed in the matrix, resulting in the best comprehensive mechanical properties, with an ultimate tensile strength, yield strength, and elongation of 498.1 MPa, 413.7 MPa, and 8.2%, respectively. The optimized heat-treatment condition provides a practical route for achieving a favorable strength–ductility balance in rheo-squeeze-cast AA7075 components. Full article

Polytetrafluoroethylene/Polyetheretherketone (PTFE/PEEK) corrosion-resistant coatings were prepared on the surface of 7075 aluminum alloy by the electrostatic powder spraying technique (EPST). To achieve a denser microstructure and improved hydrophobic properties, we introduced nano-CeO₂ to fill the coatings and analyzed the mechanism of its effect on the different coating structures. The corrosion resistance of the coatings was evaluated using NaCl immersion. The results indicate that nano-CeO₂ enhances the coatings by filling local defects and forming a denser microstructural barrier, thereby improving the hydrophobicity and corrosion resistance of the composite coatings. Additionally, the addition of nano-CeO₂ to the 20 µm PTFE/PEEK composite coating increases structural heterogeneity and pore defects, reduces coating densification, and facilitates the penetration of corrosive media, thereby weakening the barrier capability of the coating. However, in the 50 µm PTFE/PEEK/CeO₂ composite coating, nano-CeO₂ particles fill part of the pre-existing defects and improve coating densification, thereby increasing the resistance to the penetration of corrosive media through the coating. This enhanced barrier effect delays the contact of corrosive media with the substrate and improves the corrosion resistance of the coating. In this study, the 50 μm PTFE/PEEK/CeO₂ composite coating with a nano-CeO₂ content of 0.5 wt.% exhibited the best corrosion resistance, with a corrosion current density of 8.02 × 10⁻⁴ μA·cm⁻², while |Z|_0.01Hz remained above 10⁶ Ω·cm² after 720 h of immersion in NaCl solution. Full article