As a fundamental pillar for fostering new quality productive forces, constructing a modern industrial system and safeguarding national comprehensive security, the new materials industry underpins the core competitiveness of high-end manufacturing and cutting-edge technologies. Today's global industrial landscape is undergoing profound restructuring driven by four pivotal forces：intensifying geopolitical competition, worldwide carbon peaking and carbon neutrality transitions, in-depth integration of digital and intelligent technologies, and targeted iteration of materials spurred by diverse downstream application scenarios. In parallel, artificial intelligence, big data and high-throughput computing are revolutionizing the traditional trial-and-error R&D paradigm of materials science, enabling data-driven material screening, inverse structural design and intelligent process optimization to drastically cut research cycles and experimental costs. This paper systematically sorted out the opportunities and structural risks confronting the global new materials industry, and thoroughly reviewed the strategic arrangements rolled out by the United States, the European Union, Germany, the United Kingdom, Japan and Russia in 2025 and 2026. U.S. tied new materials closely to national defense and technological security, launching special programs including Crystal Palace and Carbon Crunch for military advanced materials, and consolidated independent supply chains for semiconductor materials through the CHIPS and Science Act, alongside initiatives to supervise critical mineral resources and apply AI to accelerate material innovation. EU centered its strategy on European strategic autonomy and green transformation, advancing the Advanced Materials Act and the Critical Raw Materials Act to diversify mineral supply, developed circular materials and set global green trade standards. Germany, UK, Japan and Russia had also introduced targeted national plans respectively, focusing on technological sovereignty, digitalized material R&D, military-civilian integrated innovation, rare earth recycling and import substitution amid geopolitical sanctions. After years of policy support and technological accumulation, China had achieved remarkable breakthroughs in lithium battery materials, rare earth functional materials and general carbon fibers, with a batch of national key innovation platforms and specialized sophisticated enterprises cultivated. Nevertheless, prominent internal and external vulnerabilities persisted. Externally, fierce global technological competition and restrictive trade policies created severe "bottleneck" risks, as high-end photoresists, single-crystal superalloys, core manufacturing equipment and other strategic materials still relied heavily on imports, and China lacked sufficient discourse power in formulating international material standards. Targeting six core strategic fields with prominent security risks, this study proposed targeted development frameworks for self-reliant industrial construction. For micro-nano electronic manufacturing, it highlighted localized substitution of bottleneck materials such as photoresists and electronic specialty gases, alongside R&D of low-dielectric materials and wide-bandgap semiconductor supporting materials to match advanced packaging and high-performance chip demands. For aerospace, it advocated full-chain independent manufacturing of high-performance carbon fibers, single-crystal superalloys and ceramic matrix composites to satisfy extreme service conditions of hypersonic vehicles and reusable rockets. For robotics and sensors, priorities covered lightweight structural alloys, rare earth permanent magnets and flexible sensing materials to support bionic robots and precision perception systems. In advanced nuclear energy, the paper stressed breakthroughs in radiation-resistant cladding materials and low-activation structural alloys to support fourth-generation reactors and space nuclear power sources. For marine engineering equipment, corrosion-resistant high-strength steel and deep-sea functional materials were key to advancing polar vessels and offshore renewable energy infrastructure. To systematically resolve industrial security challenges, this paper put forward multi-dimensional countermeasures covering five core dimensions. First, innovation-driven development shall be strengthened via the new whole-of-nation system to tackle generic bottleneck technologies, improve the commercialization system of scientific achievements and optimize intellectual property management for strategic materials. Second, supply chain resilience would be reinforced through domestic mineral exploration, diversified cross-border resource cooperation, national strategic mineral reserves and digital risk early warning platforms. Third, an integrated standard system aligned with international norms shall be established to fill standard gaps in high-end materials and implement full-lifecycle quality traceability management. Fourth, a multi-level talent training matrix would be optimized through industry-university-research integration, performance evaluation reforms and market-oriented incentive mechanisms to address talent shortages. Fifth, the industrial ecosystem would be upgraded through targeted policy support for industrial clusters, intelligent production line transformation and low-carbon circular manufacturing to advance high-end, intelligent and green development simultaneously. In summary, the safety of the new materials industry constituted an indispensable foundation of national industrial and scientific security. Faced with sweeping global industrial reshuffling and fierce international competition, China must advance coordinated upgrades across technological innovation, supply chain robustness, standardization, talent cultivation and industrial ecology. The conclusions and suggestions of this research could provide theoretical reference and practical guidance for constructing an independent, controllable, safe and efficient new materials industrial system, consolidating the bottom line of national scientific and industrial security, and fueling the steady growth of new quality productive forces and the advancement of new industrialization.

Silicon（Si）-based anodes are widely recognized as the most promising alternatives to conventional graphite anodes for lithium-ion batteries（LIBs）, owing to their ultrahigh theoretical specific capacity（4200 mAh·g^-1）, lowlithiation potential, abundant crustal reserves, low toxicity, and cost-effectiveness. However, their large-scale commercialization is severely hindered by two intrinsic challenges：1） drastic volume expansion（>300%）during lithiation/delithiation, which induces particle pulverization, electrode integrity degradation, and continuous rupture/reformation of the solid electrolyte interphase（SEI）films, thereby causing irreversible lithium-ion consumption； 2） extremely low intrinsic electrical conductivity（~1×10^-4 S·cm^-1）, which restricts ion/electron transport kinetics and thus degrades rate capability.To address these issues, early research efforts focused on nano-engineering of Si and the development of Si-based composites. Nanostructured Si can partially alleviate mechanical fracture by accommodating strain through size-dependent deformation mechanisms； however, it tends to agglomerate during prolonged cycling and exhibits excessive side reactions with the electrolyte, reducing the initial Coulombic efficiency（ICE）and cycling lifespan. Si/carbon（Si/C）composites design, which take advantage of the high electrical conductivity, chemical stability, and mechanical flexibility of carbon matrices, have emerged as a primary route toward commercialization. Nevertheless, challenges related to the inherently low conductivity of Si and inadequate interfacial bonding between Si and carbon remain unresolved. Against this backdrop, this review emphasized doping modification as a fundamental strategy to enhance the electrochemical performance of Si-based anodes. Starting from the lithium storage mechanism of Si—which stored lithium via an alloying/dealloying reaction to form various Li-Si alloys, with a theoretical maximum lithiation phase of Li₂₂Si₅ accommodating 4.4 Li atoms per Si atom—and its core limitations, we systematically analyzed the regulation mechanisms and functional effects of different doping approaches. These were categorized into three types：non-metallic （heteroatom） doping, metallic doping, and multi-element co-doping. Non-metallic doping（e.g., with B, P, N, or S）effectively modulated the electronic structure of Si-based materials, improved Li⁺ transport pathways, enhanced electronic conductivity, and promoted the formation of a more stable SEI layer. Metallic doping was subdivided into two categories：electrochemically inactive metals（e.g., Fe, Ti）, which enhanced electrical conduction and provided mechanical reinforcement to alleviate volume expansion, and electrochemically active metals（e.g., Mg, Ge）, which contributed additional capacity and helped accommodate volume expansion through synergistic alloying behavior. Multi-element co-doping（including non-metal/non-metal and metal/non-metal combinations）achieved synergistic optimization of multiple physicochemical properties, thus further enhancing conductivity, structural stability, and fast-charging performance. Finally, this review outlined future perspectives for doping modification technologies in Si-based anodes, including the exploration of novel co-doping systems to simultaneously address conductivity, volume expansion, and SEI stability； the optimization of doping processes for precise control over elemental distribution and concentration； and the integration of in-situ characterization techniques to deepen the understanding of the influence of doping elements on the lithium storage mechanism. This review aimed to provide fundamental theoretical insights and practical technical guidance for the development of high-energy-density and fast-charging Si-based anode materials, thereby accelerating their commercial adoption.

Thermal barrier coatings （TBCs） are advanced materials systems extensively applied in extreme environments, such as aeroengine hot-section components and gas turbines, due to their exceptional thermal insulation properties. These coatings typically consist of a ceramic top coat （TC） for thermal protection, a metallic bond coat （BC） to enhance adhesion and provide oxidation resistance, and nickel-based superalloy substrate. Despite their widespread use, the failure modes of TBCs under thermal cycling and mechanical stresses, mainlydelamination and spallation, are closely tied to the interfacial mechanical properties between eachlayers. Consequently, comprehensive and quantitative characterization of the interlaminar mechanical properties of nickel-based superalloy heterostructures with TBCs from room temperature to 900 ℃ is essential for offering valuable insights into the strength degradation patterns of these interfaces under realistic service conditions. To investigate the bond strength and interlaminar shear strength of TC/BC/superalloy substrate interfaces in TBCs, quasi-static simple tensile tests were systematically conducted over the temperature range from room temperature to 900 ℃. A controlled tensile load was applied to the coated specimens until failure occurred, allowing for the determination of the bond strength at the interfaces. The testing machine was equipped with a video extensometer, enabling non-contact real-time acquisition of displacement. The test specimens, prepared to ensure uniform coating thickness and adherence to standard specifications, were subjected to controlled tensile loading while being monitored for deformation and failure. A high-precision 4k industrial camera was positioned to capture detailed images of transverse crack propagation as well as the morphology of the fracture surfaces upon failureafter the experiments. This observational data provided valuable insights into the failure mechanisms and the nature of interfacial debonding. Additionally, to quantitatively assess the bond strength and interlaminar shear strength, the shear-lag theoretical model was employed. This model facilitated the development of an analytical method for interfacial stress transfermechanisms between the different layers of TBCs, allowing for the calculation of key parameters such as normal and shear stress distributions. Finite element analysis （FEA） incorporated with linear elastic constitutive theory was adopted to accurately represent the material behavior under tensile loading was also utilized to simulate the stress distribution within the coating and at the interfaces, providing additional validation and insights into the theoretical model. The results of the experimental studies revealed significant temperature-dependent variations in the interfacial mechanics of the multilayer hetero-structures of nickel-based superalloy with TBCs. The shear-lag theory analysis further quantified the bond strength and interlaminar shear strength of the top coat/bond coat/superalloy substrate interfaces in TBCs, confirming the theoretical predictions and providing a deeper and more nuanced understanding of the stress transfer mechanisms between the different layers. For BC/substrate interface, it was observed that the bond strength of the bond coat/substrate interface decreases markedly with increasing temperature. At 800 ℃, for instance, the bond strength exhibited a reduction of approximately 31.4% compared to its value at room temperature. This trend was attributed to the weakening of interatomic bonds and the potential for interfacial oxidation at elevated temperatures, which can weaken the interfacial adhesion. Similarly, TC/substrate interface demonstrated a comparable temperature sensitivity, with a notable reduction in interlaminar shear strength observed as the temperature rose. Particularly within 300~400 ℃, TC/substrate interface experienced a sharp decline in strength, with a 20% decrease recorded over this temperature interval. This behavior can be related to the thermal expansion mismatch between the top coat and the substrate. The high-resolution imaging provided by the industrial camera offered detailed insights into the crack propagation paths and fracture characteristics and donated a clear understanding of the failure mechanisms in TBCs. Cracks were observed to initiate at the interfaces and propagate transversely, weakening the structural integrity of the coatings and leading to eventual delamination and spallation of the coatings. Statistical methods were used to measure the average spacing of multiple cracks, and then the interfacial mechanical properties were quantitatively determined based on the shear-lag theory. The high-temperature experimental investigation of interface mechanical properties in multilayer hetero-structure TBCs, observed temperature-dependent variations in bond strength underscored the importance of considering thermal effects in the design and application of TBCs. The research contributes to the broader field of materials science by providing a deeper understanding of the failure mechanisms in TBCs and offering practical recommendations for improving their performance and reliability in extreme thermal environments. As aero-engine and gas turbine technologies continue to evolve towards higher operating temperatures and efficiencies, the knowledge gained from this study will be instrumental in advancing the development of next-generation thermal barrier coatings.

The rapid advancement of industrialization and urbanization in recent years has significantly intensified global environmental challenges. Among these, nitrogen oxide （NO_x） emissions stand as a key factor contributing to environmental issues such as acid rain, photochemical smog, stratospheric ozone depletion, and the greenhouse effect. As NO_x emissions continue to rise with global industrial output, the development of effective control and reduction technologies has become an urgent priority. Selective catalytic reduction （SCR） technology, particularly ammonia-based SCR （NH₃-SCR）, has emerged as one of the most efficient methods for removing NO_x from flue gases. In this process, NH₃ serves as a reducing agent to selectively convert NO_x to harmless N₂ and H₂O over a solid catalyst. Therefore, the catalyst is essential for lowering the activation energy, enhancing the reaction rate and selectivity, while expanding the reaction temperature window. In the quest for advanced catalysts, metal-based metal-organic frameworks （MOFs）, composed of metal ions or clusters with organic ligands, have attracted increasing attention as potential SCR catalysts due to their unique pore structures, high specific surface areas, and controllable chemical environments. MOFs provide a large number of active sites for reactions, effectively improving catalytic reaction efficiency. Incorporating transition metals such as manganese （Mn）, copper （Cu）, and iron （Fe） endows MOFs with outstanding redox properties, making them promising candidates for catalytic NO_x removal. Furthermore, the modular nature of MOFs allows for precise structural tuning, enabling the design of tailored catalysts for gas-phase reactions such as NH₃-SCR. Despite these advantages, most of MOF catalysts are sensitive to moisture. During real flue gas treatment processes, they are frequently exposed to high-humidity environments, which can lead to MOF deactivation, commonly referred to as the “water poisoning” phenomenon. This is primarily attributed to the hydrolysis of metal-ligand coordination bonds, the collapse of the MOF framework, or the blockage of active sites by water molecules. Such drawbacks severely limit the long-term stability and industrial applicability of MOF-based catalysts. To overcome these limitations, researchers have delved into the mechanisms underlying MOF water poisoning and developed effective strategies to enhance water resistance. This review systematically summarized recent advances in water-resistant modification techniques for transition metal-based MOF denitrification catalysts in NH₃-SCR applications. Three main strategies were discussed. The first involved introducing hydrophobic functional groups onto MOF surface or organic ligands to repel water molecules and prevent hydrolytic degradation. The second focused on strengthening metal-ligand bonds through ligand selection or secondary metal doping to enhance the stability of the coordination framework. The third employed surface protection techniques, such as coating MOF particles with hydrophobic polymers or constructing core-shell structures, to physically isolate the active core from moisture. Specifically, for Mn-based MOFs, researchers had devoted efforts to optimizing pore structures and regulating metal ion distribution, thereby preventing pore blockage by water molecules, enhancing water resistance, and increasing the availability of active sites. Additionally, the introduction of a second metal （such as Fe or Ce） could strengthen the coordination framework and enhance catalytic synergistic effects, while the incorporation of hydrophobic groups could protect active sites from moisture. Cu-based MOFs had been successfully modified by forming hydrophobic coatings or integrating hydrophobic polymers, effectively mitigating structural degradation under humid conditions. For Fe-based MOFs, doping with other metals or surface hydrophobic modification had further improved their inherent thermal stability and redox capabilities, enabling them to maintain high activity and structural stability in moisture-rich environments. This review systematically analyzed the mechanisms of water-induced deactivation, summarized modification strategies, and delved into the structure-performance relationships of transition metal-based metal-organic framework denitrification catalysts. These insights provided a solid foundation for the rational design of next-generation MOF catalysts with enhanced water resistance, catalytic efficiency, and long-term durability. Looking forward, the development of durable, high-performance MOF catalysts would play a pivotal role in advancing NH₃-SCR technology, reducing NO_x emissions, and promoting clean air and sustainable development. This review aimed to offer valuable references for the design and application research of future water-resistant denitrification catalysts.

As a high-performance copper-based alloy, CuCrZr alloy is widely used in electronic information, rail transit, aerospace, and other fields due to its excellent mechanical and thermoelectric properties. However, traditional preparation processes such as casting and extrusion face urgent needs such as improving production efficiency, shortening process flow, and reducing production costs. Although additive manufacturing technology can achieve near-end forming at the component level, due to the high reflectivity and rapid heat dissipation characteristics of copper alloys to infrared lasers, the improvement of tissue density and process stability faces important challenges. The rapid solidification and plastic deformation in twin-roll casting technology are carried out simultaneously, which is helpful to realize the synergistic improvement of microstructure and properties, and has outstanding advantages such as high efficiency, short process, and low energy consumption. It can provide the possibility for high efficiency and a short process of continuous forming of CuCrZr alloy. However, the high temperature deformation behavior of CuCrZr alloy after solidification is still unclear, and there is a lack of theoretical guidance for equipment load evaluation and process parameter control. The twin-roll casting process has high temperature and low strain rate, but the existing research on the flow behavior of CuCrZr alloy mostly focuses on the high strain rate conditions below 850 ℃, where the flow stress close to the liquidus is small, and the test is very difficult. Based on the Arrhenius model, the functional relationship between the flow stress, strain rate, and deformation temperature of the material can be established, which can describe the flow behavior of the material during high temperature deformation. However, the material parameters α, n, Q, and lnA are simplified by the average value, and the variation with the deformation temperature and strain rate is not taken into account, which cannot meet the prediction requirements of the high temperature flow behavior of the near liquid phase. It is urgent to improve the accuracy of the constitutive model, guide the optimization of the roll-casting process window, and reduce the process exploration cycle. To explore the flow behavior of CuCrZr alloy under high temperature conditions, the high temperature compression properties of CuCrZr alloy were tested by Gleeble-3800 test equipment at deformation temperatures of 650~950 ℃ and strain rates of 0.01~10 s^-1. The activation energy and material parameters were regarded as functions of temperature and strain rate. The high temperature flow stress model of CuCrZr alloy based on parameter parameter-compensated Arrhenius equation was established. The predicted values of the model were in good agreement with the experimental values. The correlation coefficient r and the average absolute relative error（AARE）were 0.99617 and 4.2%, respectively. To explore the suitable twin-roll casting process window, the peak stress at the deformation temperature of 650~1050 ℃ was predicted based on the constitutive model. At the same time, based on the predicted peak stress, the change law of peak stress at different deformation temperatures and strain rates was compared and analyzed. In the twin-roll casting process, the molten pool was narrow and closed, accompanied by high-temperature solidification and plastic deformation, which made it difficult to detect the temperature of the casting zone. The outlet temperature of the casting zone was usually used as one of the key detection indicators. The cast-rolling zone's outlet temperature determined the material's deformation resistance, which ultimately affected the twin-roll casting process. Therefore, this paper used the outlet temperature of the hot rolling deformation zone as the key parameter for analysis. Based on the outlet temperature parameters of the hot rolling deformation zone, this paper calculated the variation law of rolling force corresponding to the outlet temperature under different parameters. Based on the above analysis, the variation law of the predicted deformation resistance was summarized. The results showed that when the deformation temperature was greater than 910 ℃, the change of the deformation resistance was relatively stable. When the deformation temperature was lower than 910 ℃, the deformation resistance would increase rapidly with the decrease of the deformation temperature and the increase of the strain rate. The law could provide a theoretical basis for the selection of mechanical parameters and process optimization of twin-roll casting equipment. Finally, CuCrZr alloy strip was successfully trial-produced based on Φ160 mm×150 mm twin-roll casting equipment. The grain distribution characteristics of the molten pool in the cast-rolling zone were obtained using an electronic universal material testing machine, Optical microscopy（OM）, Scanning electron microscopy（SEM）, and other characterization and testing methods. The tensile strength of CuCrZr alloy strip reached 431 MPa by room temperature tensile test, and the tensile strength met the medium evaluation of DIN 17666-1983 standard. The results showed that the microstructure and compactness of CuCrZr alloy strip by twin roll casting were good, which proved the feasibility of short process near net shape forming of CuCrZr alloy by twin roll casting technology.

Lithium （Li） metal anodes possess significant advantages in enhancing battery energy density due to their high theoretical specific capacity （3860 mAh·g⁻¹） and low potential （–3.04 V （vs. SHE））, meeting the requirements for high-energy-density batteries in the field of energy storage materials. Meanwhile, solid-state electrolytes （SEs） have become a research hotspot in the field of high-energy-density storage due to their outstanding advantages, including high safety and high energy density. Among them, sulfide solid-state electrolytes （SSEs） perform particularly well. Their ionic conductivity can approach that of liquid electrolytes （>1×10⁻³ S·cm⁻¹）, and they exhibit excellent mechanical properties. When matched with Li metal, they demonstrate good chemical stability. However, the growth problem of Li dendrite seriously restricts the further development of Li metal batteries. On one hand, Li dendrite triggers the decomposition reaction of electrolytes, generating a series of by-products. This not only reduces the stability of the electrolytes but also severely damages their chemical properties. On the other hand, Li dendrite has extremely strong penetrating power, which can cause cracks in the electrolytes and eventually penetrate them, leading to battery short circuits and posing significant safety hazards. Therefore, how to effectively inhibit the growth of Li dendrites remains one of the important challenges in the field of Li metal batteries. To address this issue, this study innovatively proposed to construct a mixed ion-electron conductive （MIEC） interfacial layer between SSEs and Li metal and systematically explored the mechanism by which this interfacial layer inhibited the growth of Li dendrites. Through precise regulation of the ionic and electronic conductivity properties of MIEC, it revealed that when the content of Super P （SP） was 1%, the electronic conductivity could be successfully optimized to 1.8×10⁻⁸ S·cm⁻¹ while maintaining high ionic conductivity. The performance of the symmetric cell prepared based on this had been significantly improved. The critical current density had been greatly increased to 1.6 mA·cm⁻², and it could stably cycle for up to 2800 h at a current density of 0.5 mA·cm⁻². In-depth analysis of the mechanism showed that 1%SP composite material constructed a three-dimensional ion-electron migration network in the interfacial layer, precisely optimizing the concentration distribution of Li ion migration and effectively inducing uniform deposition of Li ions. Analyses of the interfacial layer using X-ray diffraction （XRD） and scanning electron microscopy （SEM） confirmed that MIEC not only exhibited good contact performance but also showed a state of uniform Li metal deposition. In addition, the results of in-situ electrochemical impedance spectroscopy tests indicated that it could significantly reduce grain boundary impedance and effectively improved the charge transfer kinetics, making the electrochemical reactions inside the battery more efficient and stable. X-ray photoelectron spectroscopy （XPS） analysis further confirmed that MIEC still maintained high chemical stability after cycling, fully demonstrating the reliability of this interfacial layer. In the full-cell performance tests, the cell assembled with 1%SP interfacial layer exhibited excellent performance. Under the same rate test conditions, it showed higher discharge specific capacity, reaching 203 mAh·g⁻¹ at a rate of 0.1C. More importantly, at a rate of 1C, the full cell could stably cycle 1000 times with a capacity retention rate as high as 79.7%, fully demonstrating its excellent interfacial stability. In conclusion, this study successfully achieved a uniform distribution of the electric field by balancing the ionic/electronic conduction characteristics at MIEC between the electrolyte and Li metal, effectively inhibiting the nucleation and growth of Li dendrites. The research results provided new technical approaches and theoretical bases for the development of Li metal batteries and were expected to promote the widespread application of Li metal batteries in the field of energy storage.

In recent years, electrochemical energy storage has undergone significant advancements, with lithium-ion batteries gaining widespread application in various electronic devices and the automotive sector. As a critical component of battery architecture, conventional liquid electrolytes are predominantly organic solvents, which introduce safety concerns such as leakage and volatilization. In contrast, solid-state electrolytes have garnered considerable attention due to their enhanced safety, superior interfacial contact, ease of processing, and numerous other advantages. Solid-state polymer electrolytes have been shown to exhibit excellent flexibility and ease of processing. These advantages can enhance the poor interfacial contact between the electrolyte and the electrode. It has led to their emergence as a key focus area in research related to lithium metal batteries. However, the deficiencies of low ionic conductivity of polymer electrolytes, reduced mechanical properties after conductivity increase, and low lithium-ion mobility number limit its practical application. So many scholars have devoted themselves to the study of improving the ionic conductivity of polymer electrolytes. Solid-state batteries have a long history of development and many advantages. Lithium-ion batteries are highly efficient energy storage devices, but due to the limited capacity of the anode graphite, there is a need for high-energy-density batteries, which has led to a resurgence of interest in lithium metal batteries. Solid electrolytes can be divided into inorganic solid electrolytes, organic polymer electrolytes, and composite polymer-based electrolytes. While organic polymer electrolytes possess numerous advantageous characteristics, their low level of ionic conductivity has restricted their development and application. However, analyzing the studies on the ionic conduction mechanism of polymer electrolytes, it can be seen that the widely accepted mechanism is that ion transfer is achieved by the jump of lithium ions between coordination sites on the polymer chain segments and the movement of lithium ions along with the polymer chain segments. In addition, a series of research models for the mechanism have been proposed by many scholars. Currently, most researchers tend to believe that the ion transport process mainly takes place in the amorphous region. It has been established that increasing the ambient temperature results in the formation of an amorphous region within the electrolyte, thereby facilitating the movement of polymer chain segments and enhancing ionic conductivity. Consequently, the primary considerations for the design of polymer electrolytes with high ionic conductivity are the reduction of crystallinity, the decrease of glass transition temperature, and the promotion of ionic dissociation. Polymer solid electrolytes comprise a dual composition, incorporating lithium salts and polymer matrices. In this configuration, the lithium salt fulfils the role of a carrier. The electrolyte's conductivity, being of an ionically conductive nature, is primarily influenced by the lithium salt's dissociation and the flexibility of the polymer chain. Therefore, the judicious selection of a polymer matrix becomes imperative. The most common substances used as polymer matrix are poly （ethylene oxide） （PEO）, polyacrylonitrile （PAN）, polyvinylidene fluoride （PVDF）, and other polymers, each of which has its own advantages and disadvantages. The high crystallinity of PEO is not conducive to Li⁺ conduction at room temperature, so the main direction of thinking to improve the lithium ionic conductivity of PEO-based electrolytes is to reduce the crystallinity of PEO. While PAN has good mechanical strength and a wide electrochemical window, it is very incompatible with lithium electrodes, and a serious passivation reaction occurs after contacting with a lithium metal anode. The PVDF-based polymer electrolyte has a polar lithiophilic group C-F so it can dissolve lithium salts. But as a semi-crystalline polymer, it is difficult to achieve high ionic conductivity, hexafluoropropylene is introduced into the PVDF chain segment to reduce the crystallinity of PVDF itself.However, the presence of spherical particles in the PVDF-HFP-based polymer electrolyte results in a gap in the middle, thus hindering lithium-ion transport. PMMA is a lightweight and transparent polymer with low interfacial impedance between the gel electrolyte and the lithium electrode prepared on its substrate, but it suffers from low ionic conductivity at room temperature. In addition to these popular groups, there are also polycarbonate groups, silicone groups, and others. The paper focuses on the research progress of modification strategies such as interfacial optimization, construction of frameworks, and addition of fillers in different polymer matrices to compensate for the shortcomings of various polymer matrices. This review concluded with a summary of the various polymer electrolyte preparation methods, including solution casting, phase transition, in-situ polymerization, ultraviolet curing, and electrostatic spinning. Different preparation methods also had a certain effect on the ionic conductivity. There were some problems of poor interfacial contact and residual solvent side reactions brought by the non-in-situ polymerization method. The in-situ polymerization method could solve these problems by injecting the liquid precursor solution into Li-ion battery and then initiating the polymerization of the precursor solution in a specific environment. Finally, the future research directions were analyzed in the light of the future development of solid polymer electrolytes, and the application needed in lithium metal batteries：in-depth study of the ionic conduction mechanism in solid polymer electrolytes； improvement of ionic conductivity； interface engineering breakthroughs； and solid-state battery industrialization exploration.

Aluminum alloys are widely used in fields such as aerospace due to their excellent mechanical properties, corrosion resistance, and low density. The high strength of aged aluminum alloys is attributed to the formation of nanoscale metastable precipitates during the aging process. To address the challenge that conventional aged aluminum alloys suffer from severe coarsening of nano-precipitates at elevated temperatures, leading to a sharp decline in high-temperature performance, researchers have discovered that the addition of Mg and Ag to Al-Cu binary alloys leads to the formation of Ω phase, which exhibits excellent thermal stability. This not only enhances the room-temperature mechanical properties but also significantly improves the high-temperature mechanical performance. The orderly distribution of Ω phase on the {111}_α plane has garnered significant attention in materials science. Its formation mechanism, structural characteristics, and influence on alloy properties remain hot topics of ongoing research. In recent years, with the development of advanced characterization techniques such as spherical aberration corrected transmission electron microscope （AC-TEM）, three-dimensional atom probe tomography （APT）, and in-situ electron microscopy, significant progress has been made in the study of the atomic-scale structure and precipitation behavior of Ω phase, further deepening the understanding of its formation, evolution, and strengthening mechanisms. This paper reviewed the research progress of Ω phase in Al-Cu-Mg-Ag alloys, focusing on discussions in the following five aspects. Firstly, the precipitation behavior of Ω phase was analyzed. There were two main mechanisms for the precipitation of Ω phase. It was currently widely accepted that Ω phase nucleated directly from the aluminum matrix. Specifically, Mg and Ag atoms formed Mg-Ag atomic clusters in the early stages of aging, which subsequently combined with Cu atoms to precipitate and form Ω phase. However, an intermediate phase in the formation process of Ω phase had been observed in recent studies. This suggested that Ω phase might evolve from a precursor phase, Ω', providing strong support for an alternative viewpoint. Although the formation mechanism of Ω phase was still a matter of debate, the crucial role of Mg and Ag elements in the formation process of Ω phase was beyond doubt. The interactions of these elements not only affected the type and distribution of precipitates but also determined the microstructure and macroscopic properties of the alloy. Secondly, the composition and structure of Ω phase were investigated. The chemical composition of Ω phase was Al₂Cu, with a face-centered orthorhombic structure and lattice constants of a=0.496 nm, b=0.859 nm, and c=0.848 nm. The main controversy regarding the crystal structure of Ω phase focused on whether it was a variant of θ phase. Initially, researchers believed that the structure of Ω phase was different from that of θphase. However, with the development of aberration-corrected electron microscopy, it was found that the structure of Ω phase was a variant of θ phase. Unlike the interface structure of θ phase, Ω phase had a double atomic layer of Mg and Ag atoms at the phase interface, which significantly enhanced the overall stability of the phase structure. Thirdly, the thermal stability of Ω phase was studied. Ω phase exhibited excellent thermal stability, maintaining its size stability over extended periods at high temperatures. Its resistance to coarsening was superior to that of the conventional θ phase. However, as the temperature increased, the thickening rate of Ω phase accelerated, leading to a decrease in its stability. The thickening of Ω phase was mainly related to the formation of growth steps. It had been found that the formation of growth steps generated a coherent strain field, which made it difficult for coarsening steps to nucleate on Ω phase. When the service temperature was raised above 250 ℃, the increased number of coarsening steps accelerated the coarsening rate of Ω phase. Fourth, the interaction mechanism between Ω phase and dislocations was analyzed. The interaction mechanisms between precipitates and glide dislocations were mainly divided into two types：bypassing and shearing. The deformation behavior of Ω phase under room temperature tensile and creep conditions differed, but the primary deformation mechanism was shearing mechanism. In addition, this paper also explored the influence mechanism of the interaction between Ω phase and dislocations on the thickening behavior of Ω phase. Finally, this paper discussed the effects of microalloying elements on Ω phase. Microalloying elements could regulate the microstructure of the alloy by influencing the precipitation and coarsening behavior of Ω phase. By altering the number density and size of Ω phase precipitates, microalloying elements could significantly affect the properties of the alloy. Currently, the mechanisms by which microalloying elements influenced the precipitation behavior of Ω phase can be broadly categorized into the following three types：1） forming intermetallic compounds that inhibited the precipitation of Ω phase； 2） suppressing the precipitation of Ω phase while promoting the precipitation of θ' phase； 3） promoting the homogeneous precipitation of Ω phase. Moreover, relevant studies had found that the addition of Sc could induce an in-situ phase transformation of Ω phase during thermal exposure, resulting in a new phase with both high volume fraction and excellent thermal stability. Other microalloying elements also had the potential for similar interstitial ordering. Based on the current research progress, this paper provided an in-depth discussion and outlook on the potential future research priorities and development directions. The aim was to offer valuable references and insights for subsequent studies in this field, thereby promoting the further development and application of Al-Cu-Mg-Ag alloys.

With the rapid advancement of aerospace propulsion systems, the demand for high-performance materials capable of enduring extreme thermal and mechanical stresses in aeroengine components has reached unprecedented levels. Ti-22Al-25Nb （atom fraction） alloy, an orthorhombic titanium aluminide （Ti₂AlNb-based system）, has emerged as a leading candidate for next-generation high-temperature structural applications due to its exceptional combination of low density, high specific strength, superior creep resistance, and remarkable stability under prolonged thermal exposure. This alloy system primarily consists of three distinct phases：the ordered body-centered cubic （B2） phase, the hexagonal close-packed α₂ phase （derived from Ti₃Al）, and the orthorhombic （O） phase. However, the intricate interplay between phase transformations and microstructural evolution during thermal processing poses significant challenges in optimizing its mechanical performance. To address this, the present study systematically investigated the phase transformation and microstructure evolution of Ti-22Al-25Nb alloy under varying cooling conditions, with a focus on elucidating the nucleation mechanisms, growth behavior, and crystallographic orientation relationships of O phase with the parent phase. Specimens were subjected to controlled heat treatments at two critical temperatures （1060 and 980 ℃） followed by cooling at rates ranging from rapid quenching （water and oil） to slow furnace cooling. Phase identification and structural characterization were performed using X-ray diffraction （XRD） with Cu-Kα radiation. Microstructural features were analyzed via optical microscope （OM） and scanning electron microscope （SEM）. Crystallographic orientation relationships between the precipitated O phase and the parent phase （B2 matrix or α₂ particles） during the cooling process were resolved using electron backscatter diffraction （EBSD）. Macrohardness of the alloys were tested by using a macrohardness tester. The results indicated that the morphology of the precipitated O phase was significantly influenced by the cooling mode. When the alloy was cooled from a higher temperature （1060 ℃）, numerous acicular O phase precipitated formed in B2 matrix, along B2 grain boundaries, and around α₂ particles. The specimen cooled at higher rates, such as water quenching and oil quenching, showed retention of the high-temperature B2 phase, in which B2 phase was an ordered cubic phase, due to the window for phase transformation to form new α₂ phase was narrow and rapid cooling suppressed elemental diffusion, particularly of Nb elements. Moreover, the high niobium content in Ti-22Al-25Nb alloy decelerated diffusion processes and led to sluggish phase transformations. With the decrease of the cooling rate, such as air cooling and forced air cooling, the flocculent O phases consisting of numerous fine needle-like O plates gradually became the lamellar O phase. During furnace cooling, the grain boundary O phase became continuous and well-defined and the thickness and the length of acicular O phase changed greatly as well. The growth of lamellar O-phase structures developed a typical Widmanstätten structure in B2 grain. The formation of this microstructure was due to the fact that O phase had sufficient time for nucleation and growth at a slow cooling mode. In addition, Widmanstätten O phase precipitated directly from B2 phase maintained specific orientation relationships with B2 matrix, i.e., {001}O//{110}B2 and <110>O//<111>B2. When cooled from a lower temperature （980 ℃）, the increase of the phase boundary due to the presence of α₂ particles provided favorable nucleation sites for O phase, and the acicular O-phase initially precipitated aroundα₂ particles. The volume fraction and size of α₂ particles during water quenching and oil quenching were similar with the particles in as-received Ti-22Al-25Nb alloy slab since the solution temperature was lower than the forging temperature. Compared with rapid cooling following heated at 1060 ℃, B2 grain size was smaller at 980 ℃ due to the combination of low heating temperature and pinning effect of α₂ particle. During air cooling and forced air cooling, the acicular O lamellae were precipitated from B2 matrix, B2 grain boundaries and around α₂ particles. Similar to 1060 ℃ cooled samples, the fine needle-like O lamellae precipitated into flocculent clusters. As the cooling rate further decreased （furnace cooling）, the volume fraction of the floccular O phase precipitated in B2 grains and around α₂ particles greatly increased. Meanwhile, α₂ particles appeared to be decomposed and the precipitated rim-O phaseappeared in the periphery of α₂ particles. The rim O phase formed through a decomposition reaction of α₂→α₂ （Nb-lean） + O （Nb-rich） was controlled by a diffusional mechanism and maintain specific orientation relationship, i.e., {001}O//{0001}α₂ and <110>O//<11$\overline{2}$0>α₂, with the parent α₂ particles. Rapid cooling （water-quenching and oil-quenching） led to the lowest macrohardness values for both 1060 and 980 ℃ cooling conditions, attributed to the low strength of B2 phase. Aircooling and forcedair cooling enhanced alloy macrohardness due to extensive precipitation of acicular O-phase. However, partial dissolution of α₂ particles at higher temperatures （1060 ℃） reduced nucleation sites for O phase, resulting in lower macrohardness compared to 980 ℃ cooled samples. Furnace cooling drastically reduced macrohardness owing to the increased volume fraction and coarsening of lamellar O phase. In summary, macrohardness under different cooling modes primarily correlated with Ophase precipitation strengthening, and the alloy macrohardness reached a maximum value under aircooling.

Ti-6Al-4V（TC4）, as an excellent dual-phase titanium alloy, exhibits good thermal stability at high temperatures and possesses superior overall performance, leading to its extensive use in the aerospace industry. Due to the complex geometries and poor room-temperature formability of titanium alloys, hot forming processes are typically employed during manufacturing. However, TC4 alloy has a narrow hot working window, where the microstructure is highly sensitive to deformation parameters. The competition among deformation mechanisms such as dynamic recrystallization（DRX）, work hardening（WH）, and dynamic recovery（DRV）complicates microstructural evolution during high-temperature deformation. Therefore, investigating the effects of deformation parameters on microstructural evolution and corresponding deformation mechanisms is crucial. Traditionally, hot compression tests are used to evaluate alloy forming processes. However, in the complex process of hot stamping of intricate parts, tensile stresses may lead to accumulated damage, significantly reducing final mechanical performance. High-temperature tensile tests accurately reflect the stress state during material deformation. The tensile deformation behavior of titanium alloys differs in mechanism from hot compression, making it essential to elucidate the evolution of microstructure during high-temperature tensile deformation for a better understanding of mechanical property changes. Previous studies have indicated that high-temperature deformation of TC4 alloy involves complex microstructural changes such as processing hardening due to dynamic grain growth, deformation and high-temperature movement of intragranular dislocations, α→β phase transformation, globularization of lamellar α phase, dynamic recovery, and dynamic recrystallization. Consequently, material mechanical properties undergo intricate changes, necessitating exploration of TC4 titanium alloy's mechanical characteristics under different high-temperature conditions. The plastic deformation capability of the alloy fundamentally reflects the macro results of its internal microstructural deformation mechanism. A systematic study on the tensile deformation behavior of TC4 alloy within a broad temperature range for hot forming is currently lacking. Therefore, this paper conducted high-temperature tensile experiments at temperatures of 650, 700, 750, 800 and 850 ℃ with a strain rate of 0.02 s^-1, employing electron backscatter diffraction （EBSD） to analyze the tensile microstructure characteristics and deformation mechanisms of TC4 alloy post-deformation. The formation process of recrystallized grains was reflected by changes in orientation difference angles, and individual grains were selected to analyze the globularization process of lamellar structures. The phase diagrams and image quality maps were used to reveal α-β phase transformation of TC4 alloy. The results showed that：1） TC4 alloy exhibited different deformation characteristics during high-temperature tensile processes. With increasing deformation temperature, yield stress gradually decreased. At 650 ℃, yield stress increased with loading, peaks, and then rapidly decreased until fracture, exhibiting significant work hardening characteristics. At 700 and 750 ℃, yield stress reached a maximum early in deformation, followed by dynamic softening, indicating DRV characteristics. At 800 and 850 ℃, yield stress peaked early in deformation and then decreased gradually with increasing strain, where dynamic recrystallization played a dominant role, resulting in decreased strength and significantly increased elongation. 2） Fracture surface analysis revealed that at lower temperatures, dimples were smaller and deeper, with uneven distribution and presence of microcracks and numerous voids at fracture surfaces. As temperature increased, dimples became larger and shallower, indicating increased plasticity, consistent with macro trends in elongation. 3） During high-temperature deformation of TC4 alloy, significant differences were observed in microstructural morphology. At 650 ℃, primary α phase exhibited elongated distribution with relatively low equiaxed transformation. Local recrystallization occurred in grain boundaries of α-p phase, forming "necklace-like" recrystallized grains. As temperature rose to 700 and 750 ℃, dynamic softening did not fully dissipate energy from thermal deformation, leading to dynamic precipitation of lamellar α phase, with increased thickness of lamellar α phase with temperature rise. At 800 ℃, thinner α phase lamellae transformed into finer recrystallized grains, undergoing dynamic globularization process, with average DRX grain size approximately 1.04 μm. Increasing to 850 ℃, volume fraction of recrystallized grains increased, including those formed at α-p phase grain boundaries and globularization of lamellar α phase. Overall, with increasing tensile temperature, primary α phase tended towards equiaxial transformation, decreasing aspect ratio from 1.67 to 1.35, with grain size initially increasing and then decreasing. Low-angle grain boundaries（LAGBs）gradually transformed into high-angle grain boundaries（HAGBs）, with HAGBs content increasing from 11.7% to 36.1%, indicating enhanced DRX effects. High-temperature tensile process of TC4 alloy was controlled by multiple deformation mechanisms, primarily including DRV mechanism, DRX mechanism, α→β phase transformation, lamellar α phase globularization mechanism, and grain boundary sliding（GBS）mechanism. DRV and continuous dynamic recrystallization（CDRX）mainly controled flow softening process of TC4 alloy, with CDRX mechanism continuously transitioning from LAGBs to HAGBs. Discontinuous dynamic recrystallization（DDRX）phenomenon was observed even at lower temperatures（650 ℃）. α→β phase transformation was a critical factor in enhancing alloy plasticity, with decreasing volume fraction of α_p phase and increasing α→β phase transformation with temperature rise. Dynamic globularization of lamellar α phase initially occurred in thinner lamellar layers, eventually forming fine and uniform DRX grains.