Al-Li alloys are promising fuels for composite solid propellants due to their high energy density and favorable combustion characteristics. However, their application is limited by poor storage stability and inadequate interfacial adhesion. This study presents a novel dual-layer synergistic coating strategy using fluorinated alkylsilane (FAS) and polydopamine (PDA) to improve the interfacial stability of Al-Li alloys and the mechanical performance of Al-Li alloy-based propellants. The Sequential chemical deposition of FAS hydrophobic layer and PDA adhesive layer onto Al-5Li alloy particles was successfully accomplished and uniformly covered. The interfacial adhesion and wettability are increased by introducing catechol groups, which addresses the problems caused by FAS coating. Thermal analysis revealed negligible weight loss (<= 0.191 %) from organic coating decomposition, indicating minimal impact on energy density. Mechanical testing showed that the fracture stress of propellants containing Al-5Li@FP particles was significantly improved to 1.593 MPa, and even surpassed those with pure aluminum, which was 1.263 MPa. Combustion experiments further showed a significant enhancement in the burning intensity of the modified alloy powders. This study achieves synergistic improvement of stability and interfacial adhesion in Al-Li alloys via a rationally designed PDA and FAS bilayer interface. Thereby offering an innovative pathway for developing high-performance solid propellants.

Additive manufacturing has attracted considerable attention as an effective strategy for producing high-performance titanium alloy systems in both scientific research and industrial applications. The relationship between heat-treatment temperature, α-phase evolution, and mechanical performance was comprehensively evaluated in double-wire arc directed energy deposition (D-WADED) fabricated TC17 alloy (Ti–5Al–2Sn–2Zr–4Mo–4Cr), with particular emphasis on annealing and solution conditions. Annealing within the α + β phase region (600–700 °C) improved the homogeneity of the α phase; however, α phase coarsening led to a pronounced reduction in strength. High-temperature annealing in the β phase region (950 °C) induced severe α-phase coarsening and elemental segregation, resulting in a substantial decrease in ultimate tensile strength (UTS) to 798.69 MPa. High-temperature solution treatment (900–950 °C) followed by aging produced extremely coarse α phase and finely dispersed secondary α phase (αS), accompanied by elemental segregation which compromised ductility and resulted in a UTS of 1042.28 MPa, hardness of 617.20 HV, and elongation (El) of only 5.75% for the specimen treated at 950 °C. In contrast, after solution treatment in the α + β phase region followed by aging, a dual-scale bimodal matrix comprising lath-shaped primary α phase (αP) and finely dispersed αS was obtained. The optimal combination of UTS and El was achieved at a solution temperature of 850 °C (1091.73 MPa and 12.60%, respectively), representing the most favorable heat-treatment window and a significant improvement over the as-deposited condition (1022.00 MPa and 11.16%, respectively).

As the key heat storage and transfer medium in concentrated solar power (CSP) systems, molten salts’ thermophysical properties, such as thermal conductivity, specific heat capacity, and thermal stability, critically determine the systems energy conversion efficiency and economic viability. However, conventional molten salts suffer from low thermal conductivity and limited energy storage density, restricting their application in high-temperature thermal energy storage. Recent advances show that doping with nanoparticles, such as Al2O3, CuO, and SiO2, can significantly improve these properties. Nevertheless, systematic studies on quaternary molten salt systems remain scarce. In this work, we focus on the quaternary eutectic salt H15 (15 wt

Lead-free CuSnBi alloys exhibit significant potential in heavy-duty bearing applications, but Bi segregation in traditional powder sintering and casting processes severely affects the mechanical properties of the material. This study employed wire-arc additive manufacturing (WAAM) to fabricate CuSnBi/steel bimetallic composites and systematically examined their microstructure and mechanical performance. The results show that, owing to the inherent rapid solidification characteristics of WAAM, the average grain size of the CuSnBi layer is refined to 23.48 μm, and fine Bi phases are homogeneously distributed between dendrite arms as isolated spherical particles ranging from 1 to 3 μm. Concurrently, FeCu interdiffusion at the bimetallic interface establishes a strong metallurgical bond, with a bonding strength reaching 241.7 MPa. These findings demonstrate that WAAM not only overcomes the Bi-segregation problem but also offers a practical and scalable route for producing high-performance copper-based bearing materials.

Organic functionalization of highly reactive metal powders is of great significance for chemistry and materials science yet remains a critical challenge. Herein, the interfacial self-polymerization cross-linking strategy based on boroxine chemistry is proposed to construct a functional dynamic covalent network on Al-Li alloy powders. The 4-hydroxyphenylboronic acid (HPBA) monomers undergo spontaneous dehydration and interfacial polymerization to form a trimer structure with boron-oxygen (B-O) dynamic covalent bonds in ethyl acetate solvent under vacuum and thermal conditions. During subsequent desolvation process, the HPBA trimer is further cross-linked through multimer and reactive phenolic hydroxyl groups. Dynamic B-O bonds in the boroxine structure endow the network with intrinsic self-healing capability. DFT calculation and AIMD simulation indicate that boron atoms in HPBA trimer undertake sp3 hybridization to form robust B-O-Al/Li covalent bonds with 200.167 kJ mol-1 adsorption energy. Desolvation can generate a controllable surface morphology for the network to efficiently block corrosive media transport. This organic functionalization strategy endows Al-Li alloy-based composite solid propellants with outstanding mechanical performance (2.342 MPa tensile strength) while improving the combustion heat of Al-Li alloy fuel to 30.648 MJ kg-1 with 3.2% enhancement.

To address the issues of excessive intermetallic compound growth and weak interfacial bonding strength in Al–Sn/steel composites, Al–Sn/steel and Al–Sn/Al bronze/steel layered materials were prepared by arc deposition technology. The influence of an Al bronze interlayer on the microstructure, mechanical properties, and tribological behavior of layered composites was systematically investigated. The results demonstrate that the introduction of an Al bronze interlayer optimized the interfacial structure and phase composition of Al–Sn layer. At the interface, Al–Al2Cu eutectic layer and Al2Cu intermetallic compound (IMC) layer formed, replacing the brittle Fe–Al IMC layer. Al–Sn layer remained primarily composed of α-Al solid solution, free β-Sn phase, and Al–Al2Cu eutectic structures. However, the eutectic content increased to 14.53

High-performance Al-based components with structural-functional integration are essential in modern industry, spanning lightweight designs, energy-efficient systems, and sustainable engineering solutions. In recent years, additive manufacturing (AM) of Al alloys and Al matrix composites (AMCs) has gained significant attraction in advanced engineering due to its potential for high performance and near-net-shape fabrication. Substantial scientific and commercial progress has yielded new AM-suitable advanced alloys and AMCs. This paper provides a dedicated review focusing on recent advances in advanced Al-based materials, particularly their material design strategies and high-value-added applications. This review first outlines Al-based materials and their AM opportunities, then comprehensively surveys recent progress in developing AMed Al alloys, including high-performance Al-Si alloys by processing control, modified wrought Al alloys and tailored Al alloys for AM. Furthermore, recent advances in AM of ceramic-particle-reinforced AMCs have been highlighted, emphasizing the pivotal role of reinforcements in enhancing printability and their influence on microstructural, mechanical, and functional characteristics. Industrial applications of AMed Al-based structures in high-end products are also presented. The review provides state-of-the-art knowledge on developing and applying high-performance Al-based materials by AM and discusses current challenges and future opportunities for advancing AM of these materials.

6xxx series Al alloys are widely used as raw materials for automotive electronic wiring harnesses. Beyond lightweighting and electrical conductivity, achieving an optimized synergy between strength and plasticity is essential. However, their ultimate tensile strength (UTS) and uniform elongation (UE) exhibit a pronounced trade-off during aging, typically manifesting as a "barb-shaped" relationship. To elucidate the origin of this peculiar behavior, a quantitative framework was developed by adopting the Kocks-Mecking-Estrin (KME) model to correlate macroscopic strength-plasticity evolution with microstructural changes in Al-Mg-Si wires across different aging states. Two key parameters, the dislocation multiplication parameter ΘⅡ and annihilation parameter n, were introduced to quantify dislocation activity. A macroscopic UTS-UE model was established to reveal the "barb-shaped" strength-plasticity relationship co-controlled by ΘⅡ and n during their aging-dependent variations. Furthermore, ΘⅡ and n were parameterized as binary functions of precipitate radius r and volume fraction fv, thereby quantifying how precipitate characteristics regulate dislocation storage and dynamic recovery. Overall, an integrated quantitative predictive framework linking microstructure, dislocation dynamics, and macroscopic mechanical properties was established with ΘⅡ and n serving as the bridge. The proposed approach provides a dislocation-dynamics-based paradigm for interpreting the "barb-shaped" strength-plasticity constraints in those precipitation-strengthened Al alloys.

Focusing on the issues of poor compatibility and interfacial instability of Al-Li alloy powders in composite solid propellants, this study develops a composite coating system composed of trimethyl phosphate (TMP), methoxy polyethylene glycol (mPEG), and paraffin wax (WAX) (denoted as TPW) to regulate the particle surface interface. The coating structure and composition are characterized by TEM, ToF-SIMS, and XPS. The results indicate that TPW forms a relatively continuous and uniform interfacial layer on the particle surface. This interfacial structure improves the compatibility between Al-5Li and typical propellant components, namely hydroxyl-terminated polybutadiene (HTPB) and ammonium perchlorate (AP), stabilizing the thermal decomposition behavior and improving the mechanical performance of the propellant. Meanwhile, the combustion heat of the powder does not decrease significantly after coating, and it shows excellent combustion response characteristics. With this interfacial structure in place, a practical balance can be achieved among compatibility, structural integrity, and energy output, offering a new approach for applying Al-Li alloy powders in composite propellants.

Aluminum (Al) particles are widely used as energetic additives in propellants, pyrotechnics, and explosives due to their high energy density and ability to enhance performance. However, the agglomeration of Al during combustion can reduce efficiency, often causing the performance of metalized propellants to fall significantly short of theoretical expectations. Consequently, elucidating the detailed combustion behaviors and underlying mechanisms of Al particles is critical for the design and enhancement of high-performance propellants. The highly transient nature of propellant combustion, accompanied by violent reactions and intense luminescence, makes capturing its internal dynamics particularly challenging. This study integrates in-situ high-speed synchrotron X-ray phase-contrast imaging with combustion experiments at motor conditions to systematically investigate the combustion of Al particles within a hydroxyl-terminated polybutadiene (HTPB)-based solid composite propellant. Experiments were conducted at environmental pressures ranging from 1.2 to 5.1 MPa. We examine the effects of pressure on combustion properties, Al agglomeration, particle size distributions, and the nucleation and explosion of bubbles within molten Al particles. Key phenomena such as droplet oscillation, bubble coalescence, and explosion are analyzed. Our results reveal that internal bubbles nucleate at the liquid metal-oxide interface and remain confined to this interface during subsequent growth, coalescence, and explosion. A comprehensive model of Al particle combustion is proposed, outlining both general and pressuredependent behaviors. These findings not only advance the fundamental understanding of Al combustion in propellants but also provide critical insights for controlling particle behavior and designing high-performance metalized solid composite propellants.

Due to the high energy density and affordability, Al is widely used in energetic materials. However, the agglomeration of Al particles during combustion significantly decreases propellant combustion efficiency. With reduced agglomeration and higher combustion enthalpy, Al-2.3Li alloy presents a promising alternative. In this study, we prepare propellants with various Al-2.3Li concentrations and examine their thermal behaviors using TGA/DSC and an oxygen bomb calorimeter, as well as combustion kinetics through a CCD line-scan camera, high-speed photography, fast X-ray imaging, and condensed combustion products (CCPs) analyzed with SEM and a laser diffusion system. Compared to pure Al, Al-2.3Li shows higher combustion heat and efficiency, with a shorter ignition delay and a notable decrease in the D50 of CCPs. The evolution cycles of bubbles within molten Al/Al-2.3Li droplets were observed using high-speed synchrotron X-ray radiography. The agglomeration pathways of Al and Al-2.3Li differ significantly, and their combustion mechanisms were elucidated. This work demonstrates that Al-2.3Li is a high-energy-density metallic fuel candidate with superior combustion performance in AP/HTPB propellants, offering an approach for binary alloy alternatives. The use of fast X-ray imaging to capture agglomeration processes provides a deeper sight for studying AP/HTPB propellant combustion mechanisms.

In recent years, lithium-ion batteries (LIBs) have garnered extensive attention and are recognized as a mature electrochemical energy storage (EES) system. However, their stability and efficiency are primarily confined to room-temperature conditions, with performance significantly deteriorating at temperatures below 0 degrees C or above 60 degrees C. While extensive research has been conducted on LIBs under specific temperature ranges, a systematic and integrative review addressing the comprehensive electrochemical challenges and material innovations across an ultra-wide temperature spectrum remains lacking. This gap hinders the development of reliable energy storage solutions for critical applications such as electric vehicles in extreme climates, renewable energy grids, and deepspace exploration. This review systematically examines the advancements in wide-temperature LIBs, analyzing the impact of temperature on key performance-related parameters, including reaction kinetics and charge transfer resistance. It highlights the challenges LIBs face in extreme thermal conditions while exploring recent progress in material innovation and design strategies aimed at enhancing battery performance across varying temperature ranges. The findings from these studies offer valuable insights to propel the advancement of LIB technology, addressing the demands of harsh and dynamic climatic conditions

The hydrolysis of aluminum (Al) in pure water is regarded as a greatly promising strategy for on-demand hydrogen supply due to the high energy density of Al and the operational simplicity of the process. However, its precise reaction mechanism remains poorly understood. Here, we report an efficient smelting method to fabricate AlGaIn alloy sheet and elucidate the atomic-scale reaction pathways of the hydrolysis process. Spherical aberration correction electron microscopy, X-ray absorption fine structure, and in situ scanning electron microscopy reveal that AlGaIn alloy sheet shows a typical layered structure with rich grain boundaries and is composed of a uniform reactive surface AlGa film, AlGa1 single-atom alloys, and highly ordered In atom clusters. An optimized AlGaIn alloy sheet demonstrates excellent hydrolysis performance at room temperature when directly immersed in pure water without prior pulverization. Ambient-pressure x-ray photoelectron spectroscopy and density functional theory (DFT) calculations confirm that the hydrolysis reaction is initiated at the active sites on the reactive AlGa film and is further accelerated by a cooperative catalytic effect of AlGa1 single-atom alloys and highly ordered In atom clusters. In particular, In clusters mainly facilitate water dissociation, while AlGa1 single-atom alloys are responsible for enhancing *H combination and Al spillover.

Aqueous zinc-ion batteries represent a promising technology that offers energy storage due to their inherent safety, cost-effectiveness, and environmental benignity. However, the aqueous zinc-ion batteries are plagued by severe challenges, manifesting as uncontrollable zinc dendrite proliferation, competitive hydrogen evolution reactions (HER), and electrode passivation, which synergistic failure modes severely degrade electrode reversibility and cycling stability. To mitigate these issues, convenient thermal evaporation deposition was used to engineer a high-purity nanoscale tin coating on a conventional zinc anode. The engineered Sn interphase featuring highly oriented crystallographic planes and strong interfacial adhesion to the Zn substrate confers exceptional electrochemical compatibility. This tailored interface promotes morphologically homogeneous zinc ions deposition by regulating nucleation kinetics, mitigates dendritic growth via interfacial stabilization, and markedly enhances anode cycling reversibility by suppressing competitive reactions. The assembled symmetric cell demonstrates exceptional stability, sustaining zinc plating/stripping for over 2800 h under significantly reduced voltage hysteresis of 34 mV. By addressing the critical interfacial challenges of dendrite growth and competitive reactions, our work provides a reliable Approach to enhance the cycling stability of aqueous zinc battery anodes.

Lithium-ion batteries (LIBs) suffer from pronounced capacity fading, curtailed cycle life, and increased safety risks under low-temperature conditions, primarily due to the intrinsic limitations of conventional electrolyte systems in regulating interfacial chemistry and ion transport. In this work, we report a molecular-level electrolyte design strategy that fundamentally reconstructs the Li+ solvation environment by incorporating the high-donornumber solvent N-methylpyrrolidone (NMP). The strengthened Li+-solvent coordination effectively suppresses the co-intercalation of propylene carbonate (PC) into the graphite anode while concurrently inducing the formation of a robust, ionically conductive solid-electrolyte interphase (SEI), thereby markedly enhancing interfacial stability under extreme temperatures. Moreover, the synergistic use of dual Li salts, LiTFSI and LiDFOB, further optimizes interfacial chemistry and accelerates ion-transport kinetics, where LiTFSI enhances bulk ionic conductivity and LiDFOB stabilizes interfaces to promote fast Li+ diffusion. Comprehensive experimental characterizations, combined with theoretical calculations, unambiguously demonstrates that the engineered electrolyte delivers superior electrochemical performance across an extensive temperature range from -30 to 60 degrees C. Notably, the LiCoO2//Li cell maintains a high initial discharge capacity of 125.2 mAh g-1 after 100 cycles with a capacity retention rate of 85.5%. In comparison, the LiNi0.8Mn0.1Co0.1O2//graphite cell exhibits an excellent capacity retention of 100.2% (122.5 mAh g-1) after 50 cycles at 0.05 C and -30 degrees C, electrolyte design strategy for developing next-generation wide-temperature batteries.

Liquid metal embrittlement is a phenomenon in which the mechanical properties of a metallic material are significantly reduced after contact with liquid metal, and the microscopic mechanism of this phenomenon is still controversial. The grain boundary penetration mechanism has recently been widely recognized, but the theory is still deficient. To refine the theory of grain boundary penetration, in this paper, the liquid metal embrittlement mechanism of aluminum by gallium is obtained by in situ EBSD, combining it with the fracture morphology features and comparing the differences of the microscopic feature changes and the crack evolution process during the in situ tensile process of embrittled and untreated aluminum specimens. The results show that the fracture elongation of aluminum decreased by 60% after being embrittled by liquid gallium at 80 °C for 40 min, and the gallium atoms entering the aluminum interior decreased the grain boundary cohesion while promoting dislocation emission. Combining the experimental results and previous studies, we divide the fracture of aluminum after liquid metal embrittlement into three stages, namely, the grain boundary penetration stage, the local fracture stage, and the integral failure stage.

The new generation of cast Al-Cu-Li alloys offers a benefit in both high strength and stiffness, while the ductility of these alloys is generally poor, restricting their application in aerospace industries. In this work, the cast Al-CuLi alloy micro-alloyed by Ti, Zr, and Sc was prepared by argon-shielded metal mold casting. The as-cast alloy possesses the complete equiaxed grains which exhibit good resistance to coarsening during solution annealing treatment. The microstructure including secondary phase, grain size, and precipitates were characterized by SEM, EBSD, and TEM, respectively. We find that the using of rare earth element Sc combined with its dragged effect on precipitation kinetics at 120 degrees C can optimize the strength-ductility balance of the cast Al-Cu-Li alloy. The alloy yields evident heterogeneous nucleation of " delta '+theta' " precipitates with delta ' phase wetting outside theta ' layer around Sc-clusters when aged at 120 degrees C for 100 h. Those fine precipitates result in an improved work-hardening capability compared to the coarse " T1+delta '+S' " precipitates forming at 160 degrees C aging process. Applying those principles to the new cast Al-Cu-Li alloy, a combination of mechanical properties with tensile strength at 482 MPa and elongation at 6.0 % has been achieved.

Aluminum-lithium alloy powders receive extensive concern as metal fuel in propellants for high heat value and coefficient of combustion. However, the presence of highly active metal lithium leads to the instability of alloy powder, limiting its application in propellants. Herein, the fluorination-energetic modification is developed to solve the activity problem of aluminum-lithium alloy (Al-5Li, Li 5 wt%) powders and increase their energy level. The first fluorinated layer is constructed by fluorosilane and epoxy silane coating to achieve the modifiable and functional aluminum-lithium alloy (Al-5Li@FS). Afterwards, the energetic layer is coated on Al-5Li@FS surface by glycidyl azide polymer (GAP) to obtain the fluorination-energetic composite powders (Al-5Li@FSG). The microstructural and chemical composition characterizations of Al-5Li@FSG are performed by SEM, FTIR, XPS, TEM, and TOF-SIMS. TG-DSC results show that the coated alloy powders can exhibit excellent thermal properties with remarkably enhanced exothermic enthalpy and thermal weight gain. The Al-5Li@FSG shows significantly improved combustion performances with reduced ignition delay time and repressed agglomeration phenomenon. Furthermore, hydrophobicity, water-reactivity, and compatibility with propellant components are also well modified of the Al-5Li@FSG. This work provides a guideline for preparing aluminum-lithium alloy powders with remarkable stability, excellent combustion performance, compatibility, and high energy level.

The development of solar-driven photothermal materials for efficient wastewater treatment remains a significant challenge. Herein, we have designed and synthesized a series of FeMnCo-based high-entropy alloy powders (HEAPs) with exceptional photothermal conversion, antibacterial properties and dye degradation capabilities. Under visible light irradiation, FeMnCoTiV HEAPs demonstrate a solar absorption efficiency of 85.6% across a broad solar spectrum range (200-2500 nm). This broad absorption range enables HEAPs to heat water to 45 degrees C, and completely degrade Orange II within 15 minutes. Furthermore, HEAPs effectively inhibit the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Theoretical calculations of the d-band density of states (d-DOS) attribute the wide absorption range and high efficiency to the optimized distribution of 3d electrons, particularly influenced by the high proportion of Ti and V states in the alloy. The distribution which correlated with d-d interband transitions indicated that the solar absorption properties could be controlled by adjusting elemental composition. These findings not only open additional pathways for wastewater treatment but also provide insights for the composition design and industrial applications of HEAPs.