With the increasing demand for energy storage， higher requirements have been put forward for the cycle life， capacity， working stability， and rate performances in batteries. Lithium-ion batteries （LIBs） are favoured for their excellent electrochemical performance and broad development prospects and have been widely applied in mobile devices， electric vehicles， and other fields. However， the bottleneck factors such as life decay and high cost have hindered the further promotion and application of LIBs. This article reviews the main factors affecting the cycle life decay of LIBs， including damage and gas production of positive electrode materials， as well as the consumption of active lithium caused by the repair of negative electrode solid electrolyte interface （SEI） membrane and the formation of lithium dendrites. Effective ways for scientific researchers to improve the life properties of LIBs in recent years， including the structural design of negative electrode materials and the control of SEI film stability， as well as ion doping and surface coating of positive electrode materials， are also summarized. Finally， the future development trends in this field from three aspects， such as multi-element doping， uniform coating new technology， and stable SEI film control are proposed based on the bottleneck issues in the development of lithium-ion batteries.

Sodium-ion batteries have garnered significant attention owing to their abundant sodium reserves， cost-effectiveness， and operational principles akin to lithium-ion batteries， exhibiting immense potential for large-scale energy storage applications. The advancement of sodium-ion batteries with rapid charge-discharge capabilities can effectively cater to frequency modulation needs in large-scale energy storage systems. As a pivotal component， the electrolyte in sodium-ion batteries plays a crucial role in electrode/electrolyte interface reactions and significantly influences the fast-charging characteristics of these batteries. This paper delve into the opportunities and challenges associated with fast-charging electrolytes in sodium-ion batteries. Furthermore， we discuss the intimate relationship between the fast-charging performance of sodium-ion batteries and the properties of the electrolyte， focusing on the electrolyte’s transmission characteristics and electrochemical stability. Lastly， we summarize the current development status of fast-charging electrolytes based on various solvent systems and propose a general design strategy. The comprehensive analysis presented in this paper offers valuable insights and guidance for the research and development of sodium-ion batteries with rapid charge-discharge capabilities.

In recent years，sodium-ion batteries have become a research hotspot in the world and are gradually moving toward industrialization. However，they still have shortcomings，including phase transition，structural degradation，and voltage plateau. Therefore，the development of positive electrode materials with better performance plays a crucial role in the capacity and energy density of sodium-ion batteries. This paper meticulously introduces three primary categories of positive electrode materials for sodium-ion batteries： transition metal oxides，polyanions，and Prussian blue. It elucidates the unique advantages of each material in diverse applications，acknowledges their inherent limitations，and presents a range of improvement strategies to address the challenges of low capacity and energy density. Additionally，by examining the investment trends and industrial layouts of sodium-ion battery positive electrode materials，this study analyzes the industrialization pathways and current development statuses of these three systems，summarizing the latest research advancements. Therefore，it is anticipated that with the ongoing maturation of theoretical foundations and industrial advancements，sodium-ion batteries will rapidly develop，and gradually integrate into daily life.

Lithium-ion batteries have been a crucial and indispensable energy storage system in the energy technology. Developing Li-ion batteries with high energy density，extended cycle life，and cost-effectiveness is a central challenge. Silicon material，distinguished by its impressive theoretical capacity of 4200 mAh·g^-1 and low price，has emerged as a promising candidate for negative electrode material. However，its substantial volume expansion，reaching up to 300% during charging and discharging cycles，poses a formidable commercial hurdle. To date，three generations of silicon-carbon negative electrode materials have undergone iterative development. This review focuses on three generations of silicon-carbon negative electrode materials fabricated via the CVD method. The material structure design，experimental methodologies，reaction mechanisms，and material properties are analyzed. The strengths and weaknesses of these three generations of preparation techniques are summarized，and insights into the future direction of silicon-carbon negative electrodes in Li-ion batteries are provided.

With the rapid development of modern technology，there is an increasing demand for energy storage systems that can operate stably in extreme environments，especially in cutting-edge fields such as unmanned aerial vehicles，electric vehicles，and deep-sea exploration. Lithium-ion batteries，due to their high energy density，long life，and lack of memory effect，have become an ideal choice to meet the energy needs in these extreme environments. However，harsh conditions such as extreme temperatures，impacts，and pressures pose serious challenges to the performance and safety of batteries. This article reviews the failure behaviors and mechanisms of lithium-ion batteries in various extreme environments in recent years，focusing on the changes in the internal material structure of the batteries，lithium ion transport，and electrochemical reactions to explore the internal material failure mechanisms of lithium-ion batteries under various extreme conditions. Finally，the article summarizes the main measures to improve the performance of lithium-ion batteries in extreme environments. It is hoped that these studies can guide the design of more durable and efficient lithium-ion batteries in the future，promoting the development of lithium-ion batteries in a wider range of fields.

Different crystal forms of manganese dioxide （MnO₂） are synthesized using KMnO₄， MnSO₄·H₂O， （NH4）₂S₂O₈， and hydrochloric acid as raw materials by precisely controlling the temperature and duration of a hydrothermal reaction. The structure and morphology of the materials are characterized using XRD， SEM， and TEM. The results show that the synthesized MnO₂ nanoparticles display different microscopic morphologies depending on their crystal forms. A comparison of their electrochemical performances indicates that δ-MnO₂， due to its unique flower-like structure， provides many reaction sites， leading to superior performance compared to other crystal forms of manganese dioxide. At a current density of 2 A/g， δ-MnO₂ achieves a capacity of 623.48 mAh/g after 1400 cycles. The kinetic properties of the MnO₂ electrode are investigated using cyclic voltammetry， electrochemical impedance spectroscopy， and constant current intermittent titration techniques. It reveals that δ-MnO₂ exhibits a higher Li⁺ diffusion rate.

With the development of portable electronic devices and electric vehicles， the energy density of traditional lithium-ion batteries is approaching their theoretical limit. The research on lithium metal batteries with high energy density has been re-focused. However， the high reactivity of lithium increases safety risks and reduces energy density when excess lithium is used. Anode-free lithium metal batteries （AF-LMBs） have emerged as a solution. AF-LMBs possess high energy density and the lowest redox potential. But they have poor cycle life， limited active materials， and complex interfacial reactions. Improving the cycle stability of AF-LMBs is key to realizing the application of high-energy-density storage systems.This paper reviews the development of AF-LMBs and analyzes in depth the current challenges they face from four aspects： lithium dendrites， electrolyte stability， solid electrolyte interface （SEI）， and current collectors. These factors together affect the cycle stability， safety， and energy density of AF-LMBs. Finally， it is pointed out that the future research directions should focus on optimizing electrolyte formulations， designing artificial SEI layers， and improving current collector materials and structures. Meanwhile， paying attention to the volumetric energy density of batteries to meet the demand for compact and efficient energy storage systems in practical applications， thereby promoting the commercialization of AF-LMBs.

Two metal-organic frameworks （MOFs）， Ce-UiO-66， and Zr-UiO-66， are synthesized using cerium ammonium nitrate （Ce（NH₄）₂（NO₃）₆） and zirconium tetrachloride （ZrCl₄） as metal salts， and 1，4-benzenedicarboxylic acid （H₂BDC） as the organic linker. The crystal structure and morphology of the MOFs are characterized by powder X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The MOFs-modified functional separators are prepared by loading Ce-UiO-66 and Zr-UiO-66 onto one side of commercial Celgard PP separators via vacuum filtration. The electrochemical performance of lithium-sulfur batteries is assembled and tested. The results show that the Ce-UiO-66 modified separator batteries demonstrates optimal electrochemical performance. At a rate of 0.2 C， the initial discharge capacity reaches 1047 mAh·g^-1， with a capacity retention rate of 77.5% after 200 cycles and Coulombic efficiency approaching 100%. Under various current rates， the Ce-UiO-66 modified cells deliver discharge capacities of 1281， 945， 768.1， 673.2， 604.7 mAh·g^-1 at 0.1， 0.2， 0.5， 1， 2 C， respectively. When returning to 0.1 C， the capacity recovers to 951.6 mAh·g^-1 with a capacity retention rate of 74.3%. The above results demonstrate that the redox-active Ce₆-oxo clusters in Ce-UiO-66 can effectively catalyze the conversion reactions of lithium polysulfides （LiPSs） and enhance the redox kinetics. Furthermore， Ce-UiO-66 possesses abundant defects and unsaturated coordination sites， which can effectively anchor LiPSs， mitigate the shuttle effect， and further enhance the electrochemical performance of batteries.

Separator modification represents a prevalent approach to inhibiting lithium dendrite growth and enhancing battery safety. In this study， lithium metal serves as the negative electrode， LiFePO₄ as the cathode， and a graphene coating modified polypropylene separator is employed. Lithium batteries are assembled and undergo rigorous testing， including cycling tests， rate capability tests， electrochemical impedance spectroscopy （EIS） measurements， and morphological analysis of the lithium negative electrode before and after cycling. The primary focus is to investigate the influence of positioning the graphene coating towards either the cathode or the negative electrode on battery performance. Cycle performance results indicate that when the graphene coating faces the negative electrode， the battery exhibits an initial discharge-specific capacity of 168 mAh/g at 0.2 C. After enduring 500 cycles， the discharge-specific capacity remains stable at 154 mAh/g， yielding a capacity retention rate of 91.67%. EIS analysis further reveals that the battery with the graphene coating oriented towards the negative electrode exhibits decreased interfacial resistance and improved reaction kinetics. Moreover， the surface of the cycled lithium negative electrode remains smooth and uniform， devoid of significant lithium dendrite formation. Consequently， lithium batteries configured with the graphene coating facing the negative electrode demonstrate superior cycle performance and heightened safety.

Prussian blue analogous compounds （PBAs） have emerged as promising candidates for cathode materials in next-generation sodium-ion batteries （SIBs）， attributed to their inherent thermodynamic stability， expansive ion intercalation/deintercalation pathways， abundant electrochemically active sites， as well as their adjustable chemical compositions and elemental ratios. However， the electrochemical performance of these materials is frequently compromised by crystal defects and high levels of crystalline and interstitial water content. This review delves into the structure of PBAs， categorizing them from both single-electron and two-electron perspectives. It examines the prevalent challenges faced by PBAs， systematically reviewing existing typical modification strategies across six dimensions： crystallinity control， defect mitigation， morphology modulation， ion doping/substitution， component optimization， and carbon coating/compositing. Furthermore， it offers insights into the current status of PBAs in transitioning from laboratory research to industrial applications. Looking ahead， this paper anticipates the development of PBAs in the realm of SIBs， expecting them to advance from the laboratory stage to industrialized applications through advancements in materials engineering and surface science.

In recent years， with the proposed goals of “carbon peaking” and “carbon neutrality”， the rapid development of new energy electric vehicles has led to a soaring demand for lithium ion batteries （LIBs）. However， the widespread use of LIBs inevitably results in a sharp increase in the number of retired batteries， making the efficient recycling and reuse of these waste batteries an urgent issue. LIBs are categorized into four main types： ternary lithium ion batteries， lithium iron phosphate lithium ion batteries， lithium cobalt oxide lithium ion batteries， and lithium manganese oxide lithium ion batteries. Among them， lithium iron phosphate lithium ion batteries stand out for their extensive applications and high recycling potential. Currently， the recycling of waste lithium iron phosphate lithium ion batteries primarily focuses on the recovery of valuable elements from cathode materials， high-value reuse of materials， and the recycling and functional development of anode materials. This paper provides a comprehensive review of recent advances in the recycling and reuse of lithium iron phosphate lithium ion battery materials， highlighting processes such as pyrometallurgical and hydrometallurgical recovery， the regeneration of cathode materials and their innovative applications in catalysts， as well as the reprocessing of waste anode graphite and the preparation of graphite-based functional materials. Finally， combined with the current technical level， the recycling and utilization of lithium iron phosphate lithium ion battery materials are summarized， and it is pointed out that the future direction of lithium iron phosphate lithium ion battery materials recycling should highlight the trend of optimization classification and recycling strategy， innovative recycling technology， comprehensive recycling， in-depth research on recycling mechanism， and optimization of electrode material design. At the same time， the challenges of future recycling technology are complex battery composition， irregular battery shape， electrolyte processing problems， and low recovery rate.

Lithium-ion batteries quickly occupy the absolute leading position in the secondary battery market because of their high energy density and long cycling life. However，battery thermal runaway frequently causes fire accidents，so battery safety research is of great importance and urgency. Separator as one of the key components of the lithium-ion battery plays a crucial role in the safe operation of the battery. The development of high temperature resistant separators with excellent properties，such as high mechanical strength，low thermal shrinkage，and good self-extinguishing，can significantly enhance the safety of batteries at high temperatures. This paper systematically reviews the latest research progress in the development of high-temperature resistant separators for lithium-ion batteries，including the modification of commercial polyolefin separators and the structural and performance studies of three common high-temperature resistant separators （polyacrylonitrile，polyvinylidene fluoride，and aramid fiber）. The characteristics parameters of separators，such as thickness，porosity，ionic conductivity，and thermal shrinkage，are summarized. Finally，the future development direction and opportunities of high-temperature resistant separators are prospected.

Continuous silicon carbide fiber reinforced silicon carbide （SiC_f/SiC） ceramic matrix composites are considered as the most promising advanced materials in the fields of hot end components of aviation turbine engines and thermal protection structures of novel aerospace aircraft due to their excellent comprehensive properties， such as light weight， high strength and toughness， high temperature resistance， and oxidation resistance. In this paper， the preparation technology of the four elementary components of SiC_f/SiC composites， such as SiC fiber， interphase， SiC matrix，and environmental barrier coating （EBC）， has been systematically reviewed， and the bottleneck problems of SiC_f/SiC composites in the future development have been proposed. The current third-generation SiC fibers possess a near stoichiometric C/Si ratio and have excellent high temperature stability and mechanical properties. The structure and oxidation resistance of interphase plays a decisive role in the mechanical properties of SiC_f/SiC composites in harsh service environments. The research frontiers are to develop novel interphases that matches SiC fiber and has excellent oxidation resistance，achieving continuous and uniform preparations of such interphases. PIP， CVI and RMI techniques are commonly employed to prepare SiC_f/SiC composites， but a single technique no longer meets the performance requirements of the composite. Hence， a hybrid technique such as the hybrid CVI-PIP technique has been employed to manufacture SiC_f/SiC composites， through which processing parameters， microstructures， and mechanical properties have been widely investigated. Environmental barrier coatings are used as a barrier to prevent SiC_f/SiC composites from corrosion and degradation by external corrosive environments. Based on the third generation Si/Yb₂Si₂O₇ EBC system， highly reliable and long life-span environmental barrier coatings can be prepared by supplementing Si sources and self-healing cracks， thereby greatly improving the service life of SiC_f/SiC composites components. To achieve a wider application of SiC_f/SiC composites， further research work should be carried out in areas such as the structural design of composite components， low-cost manufacturing， development of new anti-oxidation interphases， development of novel EBCs with anti-peeling off and anti-cracking natures， failure analysis and life prediction of composite.

As new energy vehicles proliferate and energy storage systems scale up， lithium-ion batteries confront market risks stemming from resource scarcity and price volatility. In this context， sodium-ion batteries have emerged as a promising alternative， leveraging their abundant resources to potentially complement lithium-ion batteries in large-scale electrochemical energy storage and low-speed electric vehicles. Despite the rapid surge in sodium-ion battery research and the onset of commercialization initiatives globally， several market and technological prerequisites persist， posing challenges compared to the well-established lithium-ion battery system. This article provides a concise overview of sodium-ion batteries from a commercialization perspective， tracing their development history and current industry standing. It delves into the core positive and negative electrode materials， costs， and application prospects within the existing sodium storage electrode material systems. Additionally， the article presents a forward-looking analysis of future opportunities and challenges， aiming to guide further advancements in the sodium-ion battery industry.

Sodium iron phosphate （NaFePO₄， NFP）， a cathode material renowned for its stable three-dimensional structure and high theoretical specific capacity of 154 mAh·g^-1， stands out as a pivotal component in sodium ion batteries. NFP exists in two distinct crystal structures： triphylite and maricite. The triphylite variety boasts a long lifespan and high reversible capacity， yet its structural thermodynamic instability poses challenges for conventional synthesis methods. Conversely， the maricite structure is stable but exhibits electrochemically inert characteristics due to the absence of cationic transport channels. Both structures suffer from low conductivity and sluggish reaction kinetics， hindering their industrial applications. This paper delves into the characteristics of these two crystal structures and summarizes various synthesis methods， including solid-state， hydrothermal， displacement， and electrospinning， as well as modification techniques such as crystal structure regulation and material surface modification. Additionally， it identifies the key challenges faced by NFP cathodes and presents potential solutions， while also outlining future research directions.

Polytetrafluoroethylene （PTFE）， as a special engineering plastic， has many advantages such as excellent self-lubricating properties， good chemical stability， and a wide range of operating temperatures. However， its core disadvantages are poor wear resistance and easy wear， which seriously shorten its service life. Starting from the structural characteristics of PTFE molecules， this article takes the transfer film theory as the main thread to deeply analyze the friction and wear mechanism of PTFE and the research and development process. It summarizes the tribological modification methods of PTFE， analyzes the common methods of surface modification， filling modification， and blending modification， compares the internal mechanisms of these three types of modification methods， and summarizes the development trend of composite modification. Finally， based on recent research achievements and existing problems in the research process， the research direction of PTFE tribological modification is discussed， some suggestions on the quantitative study of transfer film， the industrial feasibility of multimode type collaborative composite modification， the selection and application of modification system under actual working conditions are given.

Lithium-based batteries （LBBs） are widely used in portable electronic devices and electric vehicles， serving as a pivotal component in both current and emerging energy storage technologies. Lithium-sulfur batteries are considered as the ideal choice for the next generation of high-energy density batteries due to their high energy density （2600 Wh·kg^-1）. Due to the unique long chain structure and high adhesion force of polymer materials， it shows excellent performance advantages in the application of lithium-sulfur battery binder. This paper reviews the latest research progress and application prospect of polymer materials in improving the safety and stability of lithium batteries. The application of polymer materials in modified separators， solid state electrolytes， binders and flame retardants for LBBs is mainly discussed. In addition， the inhibition ability and mechanism of polymer artificial solid state electrolyte interface film and solid state electrolyte on dendrite growth are introduced， and the flame retardant property of polymer and its mechanism as solid state electrolyte are pointed out. Finally， based on the excellent plasticity and chemical controllability of polymers， the potential of high ionic conductivity and interface stability achieved by molecular design in LBBs energy storage is prospected.

Multi-wire arc additive manufacturing technology has the advantages of low cost and high efficiency， especially high flexibility in composition design and regulation， and has become the mainstream technology for the preparation of large-scale complex metal structural parts. Multiple wires （same or different） are fed at the same time to realize in-situ alloying in the molten pool. This method provides a feasible path for the preparation of advanced metal materials with complex compositions. This paper discusses the research progress of multi-wire arc additive manufacturing in the preparation of traditional materials such as high-performance titanium alloys， aluminum alloys， and stainless steels， as well as advanced metal materials such as functionally graded materials， high-entropy alloys， and intermetallic compounds. The problems of uneven microstructure， anisotropy of mechanical properties and insufficient forming accuracy of multi-wire arc additive manufacturing components are discussed. The development directions of multi-wire arc additive manufacturing process window， multi-process coupling， and forming process monitoring and control system are proposed， which provide a theoretical basis for the improvement and development of the multi-wire arc additive manufacturing process.

Zirconia toughened alumina （ZTA） ceramics exhibit excellent mechanical properties compared to single-phase Al₂O₃ and ZrO₂ ceramics， demonstrating broader application prospects in high-end industrial fields such as electronics， biomedicine， and semiconductors. This paper reviews the toughening mechanism of ZTA ceramics and summarizes recent research progress， both domestic and international， on three aspects： powder preparation， sintering methods， and the introduction of the third phase. It focuses on analyzing the role of third-phase incorporation in ZTA ceramics through the use of various sintering techniques and processing methods. Finally， it points out that the nano-structuring of powders， fine control of advanced sintering techniques， and exploration of the microstructure through third-phase modulation are key directions for future research.

A comprehensive long-term aging study has been conducted on the third-generation nickel-based single-crystal superalloy DD10 at temperatures of 900 ℃ and 1050 ℃. This investigation systematically analyzes the microstructural evolution disparities between dendrite regions， as well as the evolution of the distribution characteristics of the γ' phase and TCP phase under various aging conditions. The results indicate that during aging at 900 ℃， the γ' phase undergoes gradual coarsening and growth with increasing aging time. Conversely， at 1050 ℃， the γ' phase coarsens rapidly and retains a cubic shape after 100 h of aging. The trend of γ' phase coarsening and growth is consistent between dendrite regions， with minimal difference in the average size of the γ' phase within these regions under the same aging duration. Quantitative statistical analysis reveals that the coarsening of the γ' phase aligns with the Lifshitz-Slyozov-Wagner （LSW） model. Following aging at 1050 ℃ for 500 h or more， the γ' phase within the dendritic core adopts an irregular shape， and stress within the dendrites leads to the formation of a valuated structure in the γ' phase between dendrites， with the valuation direction coinciding with the primary dendrite growth direction ［001］. During aging at both 900 ℃ and 1050 ℃， TCP phase precipitation between dendrites is minimal， whereas the TCP phase volume fraction within dendrite stems increases significantly with increasing temperature and time. After aging at 1050 ℃ for 2000 h， the TCP phase volume fraction reaches 8.25%. Compositional analysis suggests that the TCP phase is likely the μ phase. Equilibrium phase diagram calculations confirm the precipitation of the μ phase in the alloy at the experimental temperatures， and TTT curve calculations indicate that the time required to precipitate the same volume fraction of μ phase is longer at 900 ℃ compared to 1050 ℃.

Aqueous zinc-ion batteries （AZIBs） have emerged as a highly competitive and promising new energy storage technology due to their high safety， high theoretical specific capacity， low cost， and simple fabrication process. In recent years， vanadium-based oxide materials have been widely used as cathode materials for AZIBs due to their high theoretical capacity， diverse valence states， and high electrochemical activity. However， challenges such as low electronic conductivity， structural instability， slow kinetics， and complex energy storage mechanisms hinder their further development and application in AZIBs. Recently， with the continuous optimization of electrode materials and the in-depth exploration of electrode reaction mechanisms， researchers discover that defect engineering strategies can effectively address these issues and enhance the electrochemical performance of vanadium-based oxide cathode materials. This review summarizes the zinc storage mechanisms of vanadium-based oxides， explores the research progress of applying defect engineering strategies to vanadium-based oxide cathode materials in aqueous zinc-ion batteries， discusses and summarizes the reasons for the improvement in zinc storage performance， and provides prospects for future research directions in defect engineering. The aim is to promote the development and practical application of high-performance zinc-ion batteries.

A wire-based friction stir additive remanufacturing （W-FSAR） method is proposed to address large cracks and material loss in aluminum alloy components during production and service. The W-FSAR tools consist of a wire feeding device， a stationary sleeve， and a screw-structured stirring head. This method effectively fills and repairs 10 mm-width and 2 mm-depth groove defects in aluminum alloy components. The results indicate the repaired sample has high repair efficiency， smooth morphology， homogeneous microstructure， and excellent mechanical properties. The dynamic recovery and recrystallization processes refine the grain size to 1.59 μm. The ultimate tensile strength and elongation of the repaired samples are （410±8） MPa and （11.9±0.9）%， respectively， which increase by 26% and 159% compared to the worn-out specimens. There are numerous dimples on the fracture surface， exhibiting typical ductile fracture characteristics.

IC21 alloy， as a new Ni₃Al-based single crystal superalloy， has become an ideal material for manufacturing a new generation of aero-engine turbine guide vanes due to its high melting point， excellent high-temperature performance， and creep resistance performance. However， turbine guide vanes have complex structures， such as deep holes and deep and narrow slots， which are difficult to be processed efficiently by traditional machining techniques. Electrochemical machining has become the main method for processing such complex structures due to its advantages， such as no tool loss， high material removal rate， and no cutting stress and thermal effect. This paper focuses on the electrochemical dissolution behavior of IC21 nickel-based single crystal alloy in NaCl and NaNO₃ electrolytes. The electrochemical reaction characteristics of IC21 alloy in different electrolytes are analysed by linear scanning voltammetric polarisation curve measurements. In addition， the dissolution characteristics and selective dissolution phenomena of the alloy under different electrolytes and current densities are investigated by current efficiency measurements and surface micro-morphology analysis. It is shown that IC21 alloy exhibits typical passivation-super-passivation transition phenomena in both NaCl and NaNO₃ electrolytes， in which the oxide layer formed in NaNO₃ electrolyte exhibits higher stability. Current efficiency measurements show that the dissolution efficiency of IC21 alloy is more stable in NaCl electrolyte， and the dissolution efficiency in NaNO₃ electrolyte gradually decreases with the increase of the current density， which exhibits different characteristics from the traditional theory. The dissolution surface morphology analysis further reveals the existence of the selective dissolution phenomenon of IC21 alloy under ECM conditions， and its microscopic mechanism is discussed. Based on the above experimental results， a theoretical model of electrochemical dissolution of IC21 alloy under different electrolyte and current density conditions is established， which provides a theoretical basis for the development and application of ECM processes for IC21 alloy.

Lithium fluorocarbon batteries have gained widespread application in areas such as implantable medical devices， military application， sensors， wireless devices， and aerospace due to their high energy density， excellent safety performance， and low self-discharge rates. The performance of lithium fluorocarbon batteries is particularly critical in extending the service life of leadless pacemakers. This article reviews the strategies for enhancing the capacity and voltage of lithium fluorocarbon batteries. The following three aspects are mainly discussed：firstly， the advancement of high specific capacity and high voltage fluorocarbon， involving the optimization of carbon source structure， pre- and post-fluorination treatment， and control of fluorination methods； secondly， the development of high-performance electrolytes， including the use of low concentration lithium salts with solvents processing high donor number， as well as reactive lithium salts and solvents； lastly， the optimization of battery manufacturing processes， particularly focusing on thick electrode and electrolyte injection processes. A comprehensive analysis indicates that by meticulously modulating the structure of carbon sources， optimizing the proportion of fluorocarbon bonds， improving electrolyte formulations， and innovating process technologies， it is possible to develop lithium fluorocarbon batteries with higher capacity and voltage， thereby effectively enhancing the service life of leadless pacemakers.

In order to obtain NiTi alloy with excellent properties， dual-wire arc additive manufacturing technology is used to control the wire feed speed of Ni and Ti wires， and precisely adjust the atomic ratio and phase composition of Ni alloy. The results show that when the Ni/Ti atomic ratio is 8∶10 in the center of the longitudinal cladding passage， the deposited NiTi alloy is mainly composed of Ti₂Ni phase accompanied by a small number of Ti-rich particles， and the microhardness and compressive strength reach 560HV and 1600 MPa， respectively. When the Ni/Ti atomic ratio is 11∶10， the Ti₂Ni phase is included in the NiTi phase， and the irrecoverable strain of 1.6% appears in the cyclic compression process. When the atomic ratio of Ni/Ti is 15∶10， the cluster Ni₃Ti phase is formed in the NiTi phase， the longitudinal fracture strain is close to 40%， and the irrecoverable strain is only 1.2% after cyclic compression， showing good superelasticity. In addition， compared with the central region of the longitudinal cladding passage， the microstructures of the transverse lapping region of the samples with different Ni/Ti atomic ratios show obvious grain coarsening and component segregation， and the compressive strength and plastic deformation ability are significantly reduced.

The sulfonated branched polybenzimidazole （sb-PBI） membranes with theoretical sulfonation degrees of 30%，40%，50%，and 60% are prepared by reacting between synthesized branched polybenzimidazole and 1，4-butane sultone for application in all-vanadium flow battery （VFB）. Among them，the sb-PBI-50 membrane shows excellent vanadium ion resistance （9.34×10^-9 cm²/min），proton conductivity （2.05×10^-2 S/cm），and selectivity （2.20×10⁶ S·min/cm³）. The coulomb efficiencies （96.26%-98.35%），voltage efficiencies （73.50%-90.19%），and energy efficiencies （71.72%-86.82%） of VFB with sb-PBI-50 membrane are higher than those of commercial Nafion 212 membrane under the current density of 80-280 mA/cm². In addition，the VFB assembled with sb-PBI-50 membrane can stably carry out 1170 charge-discharge cycles at 140 mA/cm². The chemical structure and micro-morphologies can remain stable after long-term cycles，indicating that the sb-PBI-50 membrane has good application potential in VFB.

Renewable energy plays a crucial role in sustainable development amidst the global energy crisis. Hydrogen， owing to its high calorific value and environmental benignity， emerges as a promising energy source for the future. Hydrogen produced through water splitting boasts high purity， zero pollution during production， and recyclability， thereby holding vast potential. Platinum （Pt） stands out as an exceptional catalyst for the hydrogen evolution reaction （HER）. While commercial Pt/C exhibits high alkaline HER performance， its high cost， material instability， and scarcity hinder widespread adoption. Consequently， this study focuses on developing a high-performance， low-cost， and less-noble transition metal electrocatalyst for HER via water splitting. Utilizing the thermal decomposition method， the heterostructural RuO₂-NiO/NF electrode can be industrially produced based on heterogeneous interface engineering. Specifically， Ni（OH）₂ and RuO₂·H₂O precursors are applied to a nickel foam （NF） substrate using a binder， followed by heating at 450 ℃ for 3 h in air to facilitate precursor decomposition， thereby successfully preparing RuO₂-NiO/NF heterostructure electrocatalysts. The RuO₂-NiO/NF electrodes exhibit remarkable catalytic activity and stability in alkaline HER. Characterization， testing， and density functional theory （DFT） calculations reveal that the heterostructural interface formed by the binding of RuO₂ and NiO significantly enhances catalyst performance. At the interface， charge transfer results in the creation of dual active sites， enabling selective adsorption of different adsorbates at distinct active sites. This synergistically promotes the fundamental reactions of water splitting， leading to exceptional alkaline HER catalyst performance. Under a current density of 10 mA·cm^-2 in 1 mol·L^-1 KOH solution， an overpotential of 52 mV and a Tafel slope of 47.5 mV·dec^-1 are achieved. Additionally， the turnover frequency （TOF） at 100 mV reaches 0.342 s^-1， and a stable potential is maintained at a current density of 200 mA·cm^-2 after 100 h of stability testing. In summary， a heterostructure RuO₂-NiO/NF electrocatalyst has been successfully developed based on interface engineering principles， with a comprehensive investigation of its HER catalytic mechanism. This provides a novel perspective for constructing heterostructure catalysts based on Ni compounds and their application in electrocatalysis.

With the development of fields such as aviation， aerospace， and navigation， the service conditions for high-end equipment have become increasingly stringent， placing higher demands on the manufacturing industry. Additive manufacturing technology， also known as 3D printing technology， has significant advantages over traditional manufacturing techniques in producing complex shapes and structures， and it is expected to achieve specific location printing and structural printing with unique properties in three-dimensional space. Wire-based laser directed energy deposition （W-LDED） technology， as an important branch of additive manufacturing， has notable advantages such as high efficiency， high precision， and high material utilization， making it promising for applications in the manufacturing of high-end equipment. Despite the many advantages of W-LDED technology， there are still numerous challenges regarding the selection of process parameters， multiple thermal cycles， and the precise control and repeatability of the manufacturing process. The deposition quality and manufacturing stability are influenced by various factors， and addressing these current challenges is a key focus of research both domestically and internationally. Based on this， this paper provides a detailed introduction to the current research status of W-LDED technology from three aspects： process parameter optimization， deposition quality analysis， and microstructural composition control. It analyzes the impact of different parameters on forming quality and manufacturing stability， proposes optimization strategies， summarizes the current application scenarios of W-LDED technology， and presents ideas for the future development trends of this technology，including material innovation and the development of multifuctional composites，research on forming mechanisms，establishing predictive models for process-defect-microstructure property relationships， new hybrid additive/subtractive manufacturing methods，and the development of large-scale，high-precision，and multifuctional equipment.

As lightweight and high-performance structural materials， nano-Al₂O₃ reinforced aluminum matrix composites can achieve lightweight energy saving and emission reduction， and have broad application prospects in aerospace， automotive industry， shipbuilding， national defense， and 5G electronic communication. In this paper， high energy ball milling powder metallurgy method， ultrasonic assisted casting method， friction stir method， additive manufacturing method， in-situ reaction method and other nano-Al₂O₃ reinforced aluminum matrix composite preparation technologies are introduced. The effects of nano-Al₂O₃ reinforcement， the interface microstructure between the reinforcement and aluminum matrix， the size and content of the reinforcement， the grain size of the aluminum matrix，the dispersion of the reinforcement， and the microstructure design on the mechanical properties of nano-Al₂O₃ reinforced aluminum matrix composites are analyzed and summarized. The main strengthening mechanisms of nano-Al₂O₃ reinforced aluminum matrix composites and the coupling forms of each strengthening stress are also summarized. Finally， the future development direction of nano-Al₂O₃ reinforced aluminum matrix composites in the aspects of large-size preparation technology with high reinforcement volume fraction， heterogeneous configuration optimization， and the integration of high-strength and heat-resistant structure and function are prospected.

MXene， as a new class of two-dimensional（2D）materials， has garnered extensive research interest due to its excellent electrical conductivity， efficient photo-thermal conversion ability， and rich terminal functional groups. However， the susceptibility of MXene to oxidation and its relatively weak mechanical properties have limited its widespread use in various application fields. MXene-based shape memory composites not only enhance the anti-oxidation and mechanical properties of MXene but also endow the material with intelligent response characteristics in macroscopic 3D structures. These properties open new avenues for MXene applications in information transmission， energy conversion， electromagnetic shielding， and fire safety protection. This study aims to review the research progress in MXene-based shape memory composites comprehensively and deeply analyzes their preparation methods， shape memory mechanisms， and application potential， offering valuable references for further research and development， and application of these composites. Meanwhile， the future direction of MXene-based shape memory composites in terms of efficient preparation， performance optimisation， multifunctional development， and their potential stability enhancement and commercialisation challenges are analysed to effectively promote technological advancement and innovation in this field.

NiTi shape memory alloys （SMAs） have found widespread applications due to their unique superelasticity and shape memory effects. However， traditional manufacturing methods face challenges in fabricating complex geometries and precisely controlling the microstructure NiTi alloys. Wire arc additive manufacturing （WAAM）， with its layer-by-layer deposition characteristics， offers a novel solution for NiTi alloy fabrication. This paper reviews the research progress in WAAM NiTi shape memory alloys， with emphasis on the influence of process parameters on microstructure， phase transformation behavior， and mechanical properties. The advantages and disadvantages of different arc processes （such as gas metal arc welding， gas tungsten arc welding， and cold metal transfer） in NiTi alloy fabrication are analyzed， along with recent achievements in forming quality， phase transformation temperature control， and mechanical properties through WAAM technology. Particular attention is given to the significant microstructural heterogeneity and oxidation issues arising from high heat input， low cooling rates， and repeated thermal cycling during the layer-by-layer deposition process， which adversely affect mechanical properties and superelastic performance. To address these challenges， strategies including process optimization， active cooling， third element addition， and heat treatment are proposed to improve material homogeneity. Furthermore， this paper discusses the heterogeneous structure design of NiTi alloys with other metals， highlighting the potential of WAAM in fabricating multi-material composite structures for high-performance devices. While WAAM demonstrates advantages in fabricating complex geometries and multi-material structures， challenges remain regarding oxidation， element vaporization， and poor interlayer bonding. Future research should focus on heat treatment optimization and microstructural control， development of novel multi-metal composites， and exploration of innovative approaches to enhance interfacial bonding and oxidation resistance， thereby further improving NiTi alloy performance and expanding their application domains.

The Ti/Al dissimilar welded structure combines the high strength and corrosion resistance of titanium alloys with the lightweight and formability advantages of aluminum alloys， providing a broader range of options for product design and manufacturing. Meanwhile， this structure helps reduce component mass and cost， achieving lightweight design and structural-functional integration. Friction stir welding （FSW）， as a solid-state welding method， is one of the most suitable techniques for Ti/Al dissimilar joining. However， conventional Ti/Al FSW still faces challenges such as severe tool wear， non-uniform mechanical properties along the weld thickness， potential lack of penetration at the weld root， and difficulty in precisely controlling intermetallic compounds （IMCs）. This paper reviews the improvements proposed by researchers worldwide to address these issues， exploring various innovative processes to overcome the limitations of conventional Ti/Al FSW and achieve high-quality joints. It analyzes and compares the characteristics and applicability of different modified FSW techniques， including interlayer addition at the interface， application of auxiliary external fields， modification of joint configurations， and stationary shoulder FSW. The study further explores their roles and mechanisms in enhancing weld quality and optimizing interface properties， while systematically summarizing future research directions for Ti/Al dissimilar FSW. Finally， it is pointed out that future research should focus on further optimizing modified welding processes， improving process stability， and enhancing industrial feasibility to promote the engineering application of Ti/Al dissimilar welded structures.

In recent years， with the rapid development of aerospace technology， the requirements for engine thermal efficiency and light weight are getting higher and higher， resulting in the continuous reduction of the wall thickness of turbine blades. However， the reduction in wall thickness leads to decreased properties of the alloy material for blades， i.e.， the thin-wall effect. Therefore， the study of the thin-wall effect is of great significance to the safe and stable operation of turbine engines. However， the reasons and laws of the thin-wall effect are very complicated. Based on this， this paper reviews the influence of experimental conditions， surface states of materials， coatings， polycrystals， single crystals， and anisotropy of alloys on the thin-wall effect of alloy materials for blades， and summarizes three typical cases according to the mechanism and model of the thin-wall effect： the oxidative damage model， the oxidation-creep damage model and an analysis based on crack growth. Due to oxidation and the presence of hard and brittle phases， cracks are inevitably generated in the workpiece during service. Based on the crack growth analysis， it is shown that there is a significant correlation between crack growth and thin-wall effect， providing new insights for future research on thin-wall effects.

In light of the “rich coal，poor oil，and scarce gas” resource status in China，developing carbon electrode materials from coal can accelerate the transformation of clean and efficient utilization of coal and the realization of “dual carbon” goals. Herein，the porous carbon is synthesized from Shenmu bituminous coal via a one-step KOH activation strategy. The results indicate that the resultant carbon possesses a hierarchical porous structure with a surface area of 2094.5 m²·g^-1 and pore volume of 0.96 cm³·g^-1，abundant graphitized microcrystals，N/O co-doping，and excellent hydrophilicity. By employing as-fabricated carbon as cathode，2 mol·L^-1 ZnSO₄ aqueous solution as electrolyte，and Zn foil as anode，the assembled coin-type Zn-ion hybrid supercapacitors （ZIHSCs） exhibit a high capacity of 178.7 mAh·g^-1 at 0.1 A·g^-1 and retain 89.2 mAh·g^-1 by enlarging the current density 200 times to 20 A·g^-1，manifesting an eminent rate performance. Importantly，the maximum energy density and power density of ZIHSCs can reach 142 Wh·kg^-1 and 16854.9 W·kg^-1，respectively. Furthermore，the quasi-solid ZIHSCs based on the gel electrolyte of gelatin@ZnSO₄ also deliver outstanding electrochemical capability and excellent flexibility.

The 6061 aluminum alloy billets are subjected to solution quenching treatment under a solution heat treatment condition of 550 ℃ for 30 min. After quenching， the billets are artificially aged at 140 ℃ for 6 h to 18 h to obtain pre-hardening （PH） billets. The formability and mechanical properties of the pre-hardening 6061 aluminum alloy billets are evaluated using room-temperature Erichsen cupping tests and uniaxial tensile tests. Additionally， the stamping trials for hat-shaped beam components are conducted to verify the feasibility of this technique for engineering applications. The results show that the yield strength （YS） of the PH-12 h pre-hardening billets is 186 MPa higher than that of the O-temper billets， and the tensile strength （TS） is 215 MPa higher than that of the O-temper billets， while the elongation （EL） and cupping values are comparable to those of the O-temper billets. The PH-18 h pre-hardening billets exhibit a maximum tensile strength of 391 MPa after 10% deformation， significantly exceeding that of the T6-temper aluminum alloy， demonstrating that the pre-hardening billets possess excellent strength-ductility balance. Furthermore， the hat-shaped beam components formed from pre-hardening billets exhibit tensile and yield strengths superior to those of the T6-temper aluminum alloy.

Radiation thermal protection coating based on rigid ceramic fiber insulation tile is a thermal protection system widely used in spacecraft， and improving its reusable performance such as emissivity， impact resistance， and thermal shock resistance has always been a research focus. This article reviews the research progress on the structural design and material improvement of radiation thermal protective coatings for rigid ceramic fiber insulation tiles under the background of diversified performance optimization. The structural design approach and composition adjustment ideas of radiation thermal protective coatings are analyzed， from single-layer dense structure to multi-layer gradient structure and scaly structure，and the advantages and existing problems of radiant thermal protection coatings with different structures are summarized. Finally， it is pointed out that multilayer gradient structure coatings， due to their comprehensive advantages of dense top layer and porous gradient structures and their adjustability， are still the mainstream of current research. In the future， radiant thermal protection coatings should further optimize the integrated design of thermal insulation， and conduct research on the impact of structure and composition on performance in service simulation environments.

The oxidation kinetics and microstructure of S30815 heat resistant stainless steel， both in its base material and welded joint， are analyzed at different service temperatures by the constant temperature oxidation method. High temperature oxidation kinetic curves are obtained by the mass gain method. The morphology， composition， and microstructure of the oxide films are studied by using scanning electron microscopy （SEM）， energy dispersive spectroscopy （EDS）， and X-ray diffraction （XRD）， respectively. The results show that under constant temperature oxidation conditions at 780 ℃， there is less mass gain and a relatively lower oxidation rate. The oxidation products are mainly Cr₂O₃， Fe₂O₃， and Fe₃Mn₃O₈， exhibit sheet， strip， and polyhedron shapes. At 880 ℃， the mass gain and the oxidation rate significantly increase. The oxidation product at this temperature comprises a mixed oxide of Cr₂O₃， Fe₃O₄， MnFe₂O₄， and Ni （Cr₂O₄）， which is mainly in thin strips and sheets. The oxidation kinetics curves of S30815 follow a parabolic rule. With the increase of oxidation time， the oxidation rate gradually decreases and eventually tends to be stable， showing a good oxidation resistance at high temperature. A larger amount of dense Cr₂O₃ oxide film is generated on the surface of the welded joint， exhibiting a lower average oxidation rate and better oxidation resistance compared to the base material.

This study investigates the dynamic compressive mechanical properties of three-dimensional woven carbon/carbon composites under both room temperature（25 ℃） quasi-static and from 25 ℃ to 900 ℃ dynamic compression conditions using both a materials testing machine and a split Hopkinson press bar device equipped for simultaneous high-temperature loading. The experimental results reveal that the strength of the composites is influenced by three key factors： fiber orientation， strain rate， and temperature. Specifically， under consistent strain rates and temperatures， the composites exhibit higher strength in the Z-direction compared to the XY-direction. As the strain rate escalates， the strengths of the composites in both the XY-direction and Z-direction increase， indicating a positive correlation with the strain rate. Upon heating from room temperature to 900 ℃， the strengths of both XY-direction and Z-direction composites initially rise， peaking at 600 ℃， and then gradually decline. Under both static and dynamic loading conditions， XY-direction composites undergo shear failure， albeit with a smaller shear fracture angle in the dynamic case compared to the quasi-static scenario. An increase in the strain rate results in a transition in the fracture mode of Z-direction composites， shifting from shear failure to a combination of matrix crushing and partial fiber fracture.

This paper proposes a non-isothermal solid solution-forging integrated hot forming process for 7075 aluminum alloy. After solid solution treatment， the aluminum alloy is directly placed into the mold for forging， then quenched and subjected to artificial aging treatment. The influence of water entry temperature and aging parameters on the microstructure and properties of 7075 aluminum alloy is studied under this process， through the construction of a temperature-time-property（TTP） curve. Additionally， machine learning techniques are integrated to optimize and match the key process parameters. The results reveal that the nose temperature of the TTP curve is 315 ℃， and the mechanical properties of the alloy increase with the increase of water temperature after aging， a double-peak phenomenon after non-isothermal forging and aging is observed. When the inlet temperature is 380 ℃， the optimal aging parameters are 115 ℃-26 h and the peak hardness is 182HV. After training， the prediction accuracy of the BP neural network model is 94.9977%. Experimental verification of the optimal process parameters predicted by the model shows that its prediction similarity is 96.9%. Compared with traditional forging processes， this process can achieve high mechanical properties than traditional forged T6-state 7075 aluminum alloy while reducing procedural steps and energy consumption.

The stability of micro-droplet ejection and size on-demand are important prerequisites for the direct preparation of bumps in chip packaging. The ejection experiment of SAC305 commercial lead-free solder is carried out by pulsated orifice ejection method （POEM）. The effects of the interaction of parameters such as the pulse waveform， the distance between the transmission rod and the orifice and the orifice， diameter on the ejection stability and particle size during the droplet ejection process are investigated. The surface morphology and microstructure， composition， and phase composition of the solder ball are analyzed. The results show that the stable ejection of droplets and the control of size-on-demand can be realized by coordinating the key process parameters. The deviation between the target particle size and the actual size is within 4%， which can meet the needs for the stable on-demand preparation of bumps. The results of temperature change during droplet solidification show that the cooling rate in the argon atmosphere is much lower than that in the helium atmosphere， so the microstructure is coarser. Combined with the above results， the bumps are directly deposited on the copper plate to form a metallurgical layer， which shows the feasibility of the technology and provides a new way for the direct preparation of bumps.