ABSTRACT In laser‐directed energy deposition (LDED) of TiC/Ti6Al4V composites, a low content of micron‐sized TiC provides a good strengthening effect on hardness and strength, but the improvement in plasticity remains a challenge. By introducing synchronous ultrasonic impact treatment (UIT) into the LDED process, an ultrasonic‐assisted LDED (UA‐LDED) technique was adopted to fabricate 1 vol% and 5 vol% TiC/Ti6Al4V composites. The results show that the UIT effectively reduces the lattice mismatch between TiC and α‐Ti, as well as the average grain sizes of TiC, prior β‐Ti (β p ), and α‐Ti. The ultrasonic waves interacted with the molten pool via cavitation and acoustic streaming, which could break TiC grains, promote the nucleation of β p , and suppress the growth of TiC and β p . Moreover, the ultrasonic waves also interacted with the high‐temperature deposited layer, which affected the formation of α‐Ti. Massive α‐Ti (α m ) grains observed at β p grain boundaries indicate the occurrence of massive α‐Ti transformation. UIT facilitated the massive transformation of 1 vol% TiC/Ti6Al4V and promoted the equiaxed growth of α m in 5 vol% TiC/Ti6Al4V. The α‐Ti grains inside β p grains were refined by UIT, and dynamically recrystallized grains were found. The microstructure regulated by UIT provides higher microhardness and greater elongation for the composites, while the tensile strength decreases slightly for the 1 vol% TiC/Ti6Al4V and increases for the 5 vol% TiC/Ti6Al4V. After UIT, the maximum plastic elongation of 1% TiC/Ti6Al4V increased from 1.09% ± 0.39% to 2.32% ± 0.86%, and that of 5% TiC/Ti6Al4V increased from 0.17% ± 0.02% to 0.88% ± 0.07%.
ABSTRACT Aqueous zinc batteries hold great promise for large‐scale energy storage, yet their practical application is hindered by dendrite growth and interfacial side reactions on the zinc anode. Inspired by the industrially mature chromate passivation technology, this work reports an in situ construction of a chromium‐rich passivation layer (Zn@Cr) on zinc metal via a liquid‐solid interface reaction between zinc foil and sodium chromate solution. Systematic characterization reveals that the passivation layer is composed of crystalline Cr 2 O 3 with a dense and uniform structure. Electrochemical tests demonstrate that the optimized Zn@Cr‐2 anode enables over 1400 h of stable cycling in symmetric cells (1 mA cm −2 , 1 mAh cm −2 ) and achieves an average Coulombic efficiency of 99.37% in Zn‖Cu half‐cells. When coupled with a MnO 2 cathode, the Zn@Cr‐2||MnO 2 full cell delivers an initial capacity of 218.8 mAh g −1 at 1 A g −1 and retains 179.1 mAh g −1 after 950 cycles, exhibiting excellent rate capability and long‐term cycling stability. Further mechanistic analysis reveals that the chromium‐rich layer functions both as an “interfacial shield” and a “deposition guide”: it suppresses hydrogen evolution and corrosion side reactions while inducing preferential Zn deposition along the (002) plane, thereby enabling uniform and dense zinc nucleation and growth. This study extends conventional metal surface treatment technology to the protection of battery anodes, offering a new strategy for interfacial design in high‐performance aqueous zinc batteries that combines industrial feasibility with academic significance.
ABSTRACT The development of high‐performance and cost‐effective oxygen evolution reaction (OER) electrocatalysts is critical for the large‐scale deployment of green hydrogen technologies. Among various candidates, amorphous alloys have emerged as promising OER catalysts owing to their long‐range disordered atomic structures, high energy states, and abundant unsaturated coordination sites. However, their practical performance is constrained by limited structural tunability and relatively low electrical conductivity. In this study, a general strategy involving nanocrystal introduction followed by dealloying was developed to convert FeNi‐based amorphous alloy fibers into nanoporous/nanocrystalline/amorphous (N/N/A) multiphase alloy fibers. This strategy generates a hierarchical architecture in which the interior consists of coexisting nanocrystalline and amorphous phases, and the surface region features ultrasmall NiO nanocrystals (∼2 nm), abundant nanopores, and a residual amorphous matrix. The resulting N/N/A fibers delivered a low OER overpotential of 210 mV at 10 mA cm −2 and sustained stable operation for over 700 h at 50 mA cm −2 . The enhanced catalytic performance originates from the synergistic effects of enlarged surface area, enhanced surface reconstruction, and optimized electronic and coordination environments. Importantly, the generality and effectiveness of this strategy were validated across 10 different amorphous alloys, all of which exhibited consistent performance enhancement.
ABSTRACT The low energy density of sodium‐ion batteries (SIBs) remains a major barrier to their large‐scale deployment. Alloy‐based anodes represent a promising class of materials owing to their high specific capacity and low operating potential for sodium storage. However, their practical application is hindered by severe volume expansion upon cycling. A common strategy to mitigate this issue is the incorporation of inactive components. To systematically explore optimal composite ratios, we developed a high‐throughput magnetron sputtering method capable of simultaneously preparing Sn‐based anodes with varying types and contents of inactive components. Using this approach, Sn‐based anodes doped with Cu and Al were fabricated and screened. Among the compositions tested, Sn 87 Cu 13 showed the best overall performance. It delivered 796.73 mAh g −1 at 0.5 A g −1 while retaining ∼87.49% of its capacity over 200 cycles. Furthermore, this anode exhibited excellent rate capability, sustaining a specific capacity of 577.45 mAh g −1 at 2 A g −1 . Further analysis revealed that Cu doping significantly improves both the initial Coulombic efficiency and cyclic stability. These enhancements are attributed to Cu‐induced expansion of the (200) lattice plane of Sn, which mitigates volume changes during alloying with Na. Additionally, Cu reduces the Na adsorption energy, enhancing Na capture and overall electrochemical performance.
ABSTRACT Micro‐/nanoscale single‐crystal materials have garnered significant attention due to their unique size‐dependent mechanical and functional properties, with applications spanning diverse cutting‐edge fields. This review provides a state‐of‐the‐art overview of these materials, encompassing their synthesis methods, advanced mechanical and functional properties, as well as practical and emerging applications. A particular focus is placed on the fundamentally different deformation traits observed at such confined scales, specifically localized shear/slip banding, surface relief, and serrated stress‐strain response. Such deformation instabilities are ubiquitous yet often detrimental to the integrity, lifespan, and reliability of micro‐/nanodevices. We critically analyze the physical origins of these deformation phenomena, which are rooted in crystallographic constraints, thermodynamic considerations, size effects, and dislocation mechanics. Furthermore, we summarize recent research efforts aimed at mitigating these adverse effects through strategies such as optimizing crystal qualities and edge geometries, controlling deformation conditions, utilizing specific loading geometries and crystal orientations, alloying and precipitation, surface engineering, and employing in situ observation with feedback control. This review underscores the challenges and potential solutions in leveraging the exceptional properties and attributes of micro‐/nanoscale single crystals toward the development of robust next‐generation single‐crystal‐based miniature devices.
ABSTRACT Niobium‐based refractory alloys are promising candidates for high‐temperature aerospace structures, yet their limited ambient‐temperature ductility and poor processability remain major barriers to broader implementation. Here, Nb521 alloy was fabricated by laser powder bed fusion (LPBF), and the effects of processing conditions and subsequent hot isostatic pressing (HIP) on microstructural development and mechanical response were systematically examined. The as‐printed alloy exhibited a heterogeneous grain structure composed of columnar and equiaxed grains, together with pronounced solute segregation and dense dislocation substructures generated by rapid solidification. HIP promoted chemical homogenization, reduced the fraction of low‐angle grain boundaries, weakened the crystallographic texture, and induced a partial tetragonal‐to‐monoclinic transformation of dispersed ZrO 2 particles. These microstructural modifications led to a marked improvement in the strength‐ductility balance. In particular, after HIP treatment, the specimen fabricated with a laser power of 240 W and a scanning speed of 500 mm s −1 (LED = 480 J m −1 ) exhibited an ultimate tensile strength of 581.9 ± 2.98 MPa, a yield strength of 442.2 ± 8.66 MPa, and a tensile elongation of 22.3% ± 0.62%. Quantitative strengthening analysis indicates that the yield strength arises from the combined contributions of lattice friction, grain‐boundary strengthening, dislocation strengthening, and precipitation strengthening. The precipitation contribution is governed predominantly by Orowan bypassing, with an additional contribution from particle shearing, enabling simultaneous strengthening and ductility retention. These findings clarify the microstructural origins of the enhanced mechanical performance of LPBF‐processed Nb521 alloy and provide guidance for designing additively manufactured niobium‐based alloys with improved strength‐ductility synergy.
ABSTRACT Advanced metallic glasses, leveraging their ultrahigh strength, excellent corrosion resistance, superior soft magnetic properties and good biocompatibility, have gradually become indispensable strategic cornerstones in critical fields such as aerospace, electronic information and energy power. This unique combination of properties enables them to adapt to extreme service environments, demonstrating application potential far exceeding that of traditional crystalline alloys. With the continuous development of materials science, metallic glasses are rapidly advancing toward multicomponent designs. The combination and matching of multiple elements lead to complex and diverse changes in the correlation between composition and performance, forming an extremely vast exploration space. However, the traditional “trial‐and‐error” development model is struggling to keep up, not only consuming a large number of resources but also extending the development cycle to several years. It is difficult to meet the urgent demand of modern industry for new high‐performance materials. Against this backdrop, combinatorial materials science integrated with high‐throughput characterization technology has gradually emerged. Through parallel experimental design and rapid data collection, the material screening process that originally took years is compressed into weeks. This review focuses on the combinatorial development and high‐throughput evaluation technologies of metallic glasses, with particular emphasis on compositionally graded thin‐film libraries. Such libraries can achieve continuous gradient changes in composition on a single substrate, covering thousands of different alloy ratios at one time. The review systematically integrates high‐throughput testing schemes for four core properties. For mechanical properties, the hardness, strength, toughness and wear resistance can be accurately quantified via nanoindentation technology. In the characterization of soft magnetic properties, magneto‐optical Kerr effect was used to quickly obtain core parameters such as the saturation magnetic flux density and coercivity. For corrosion resistance, two strategies based on electron work function and interatomic bond strength were innovatively adopted to reveal the corrosion mechanism. In the evaluation of biocompatibility, through quantitative analysis of antibacterial activity, the inhibitory effect of materials on common pathogenic bacteria can be intuitively judged. Through these multi‐dimensional high‐throughput characterization technologies, this review has successfully established a complete basic paradigm for the high‐throughput development of metallic glasses. In addition, this review also prospectively outlines the future development direction of metallic glass development, the deep integration of artificial intelligence‐driven closed‐loop research and high‐throughput computation. In this model, machine learning algorithms can conduct in‐depth mining and pattern recognition of massive composition‐property data generated by high‐throughput experiments, and high‐throughput computation methods can reveal the intrinsic mechanism of composition regulating performance at the atomic level. This closed‐loop system of “theoretical prediction‐experimental verification‐data feedback‐model optimization” is promoting the development of metallic glasses from blind screening relying on experience to a new stage of rational design based on data and theory. Overall, this review not only systematically sorts out the scattered research results in the field of high‐throughput development of metallic glasses, but also provides a feasible technical path for the industry, facilitating the practical application of customized metallic glasses in actual production.
ABSTRACT Self‐supporting aluminum (Al) foil anodes offer the advantages of high energy density, simplified structural configuration, and low cost. However, their practical application is severely constrained by challenges such as low initial Coulombic efficiency, pronounced interfacial side reactions, and sluggish lithiation kinetics. To address these bottlenecks, this study proposes an in situ prelithiation strategy implemented during the cell assembly stage. By bringing Al foil into direct contact with a thin lithium foil during cell fabrication, a spontaneous alloying reaction occurs during the resting period under electrolyte mediation, directly constructing an in situ prelithiated Al (IPL‐Al) foil anode within the sealed cell. It is demonstrated that this process simultaneously constructs a dual‐functional interphase structure consisting of a nanocrystalline/ultrafine‐grained LiAl host and a thin, inorganic‐rich solid electrolyte interphase (SEI). This structure lowers the nucleation barrier for subsequent lithiation, provides fast mass transport pathways, and helps suppress continuous side reactions while maintaining interfacial stability. Benefiting from this synergistic interfacial structural regulation, IPL‐Al exhibits significantly enhanced reaction kinetics and structural stability compared to pristine Al foil. The IPL‐Al||LiNi 0.8 Co 0.1 Mn 0.1 O 2 cell delivers a reversible discharge specific capacity of 211.1 mAh g −1 at 1C, with a capacity retention of 82.2% after 400 cycles. Even at a high rate of 5C, it maintains 80.3% of its capacity after 400 cycles. Furthermore, the IPL‐Al||LiFePO 4 cell exhibits only 11.2% capacity decay after 500 cycles. This work demonstrates that in situ prelithiation during the assembly stage is an effective strategy validated in full cells, providing new insights for the design and application of high‐performance, copper‐free, self‐supporting metal foil anodes.
ABSTRACT To meet the escalating demand for high‐performance LiCoO 2 (LCO) cathodes, elevating the charging cut‐off voltage becomes highly imperative to achieve markedly enhanced specific capacities. However, high‐voltage operation is always accompanied by structural instability, notably deleterious bulk phase transitions and severe interfacial degradation. Herein, we propose a collaborative strategy that integrates a medium‐entropy (Mg, Eu, and W) doped bulk architecture with an in situ formed epitaxial entropy‐assisted MoB surface coating, which effectively suppresses the detrimental surface‐initiated structural degradation, enabling a robust, high‐voltage‐tolerant LCO cathode. The synergistic co‐doping of Mg, Eu, and W not only strengthens the structural framework without crack formation but also curtails lattice oxygen loss while accelerating Li + diffusion kinetics. Moreover, the in situ generation of an entropy‐stabilized MoB coating provides exceptional resistance against corrosion induced by electrolyte decomposition. Using this design principle, the LCO featuring surface‐to‐bulk synergistic modification is endowed with exceptional wide‐temperature‐tolerant electrochemical stability at a high voltage of 4.65 V, delivering an outstanding rate capability of 153.3 mAh g −1 at 5C and long‐term cycling stability with 84.4% capacity retention after 400 cycles. Our contribution hugely advances the high‐voltage LCO cathodes toward the practical commercialization of high‐energy‐density lithium‐ion batteries.
