Advanced materials technology is the forerunner in the development of high-tech aerospace equipment and the key foundational technology supporting the modern industry. It has penetrated into all aspects of national defense construction, national economy and social life, and has become a technological highland and national defense focus that countries all around the world are competing to develop. This article focuses on analyzing the current technological status and development trend of the advanced structural materials in the aerospace field, elaborating on the aspects of high-performance polymer and their composites, high-temperature and special metal structural materials, lightweight high-strength metals and their composites, and advanced structural ceramics and their composites. The analysis results show that the current development and production of aerospace structural materials in China still face various difficulties, such as too much follow-up research and imitation, lack of independent innovation, severe technological blockade, and technical bottlenecks need to be broken. Meanwhile, the prospects for future research and development are proposed, and the significance of establishing the complete technology system of production-learning-research-application is highlighted.

With the proposal of the "dual carbon”goals, using hydrogen as zero-carbon alternative fuel has become an important trend of the aviation industry in the future. In recent years, the hydrogen-fueled aero-engines have garnered significant attention. Superalloys are the most widely used materials in the hot section components of gas turbine engines. The purpose of this review is to provide reference for the research and development of superalloys for hydrogen-fueled aero-engines future use by understanding the effects of hydrogen-related environment on superalloys currently across various fields. Internal/external hydrogen environments, hydrogen permeation（charging）methods, measurement of hydrogen concentration/distribution or stable existence temperature, the influence of hydrogen on tensile strength, the impact of hydrogen on creep/stress rupture and fatigue properties, and the fracture mechanism of hydrogen embrittlement are described. The degradation factors of mechanical properties of superalloys with different composition, manufacturing process, original microstructure, alloying degree and different application fields under hydrogen-related environment are summarized. In general, mechanical properties tests in the external hydrogen environment exhibit more significant hydrogen-assisted mechanical degradations than that in internal hydrogen environments. Superalloys with higher alloying degree exhibit more pronounced hydrogen embrittlement, while the tendency of properties decrease（creep/rupture, fatigue and tensile）in hydrogen at elevated temperature is much less than that at room temperature. The prospects for the mechanical performance evaluation of current superalloys in hydrogen-related environments for hydrogen-fueled gas turbine and the development of new alloys suitable for hydrogen environments are provided. Hydrogen-fueled gas turbine aero-engines may encounter cryogenic temperature hydrogen environment for liquid hydrogen storage, hydrogen environment for cooling, high-temperature/high-pressure hydrogen environment for gas compression, and the impact of combustion products–water vapor（humid）at elevated temperature. Diffusion or permeation of hydrogen in superalloys, the embrittlement and corrosion of alloys in high-pressure hydrogen environments, oxidation and corrosion behavior in high-temperature humid environments, as well as the degradation and protection mechanism for alloys and coatings in the aforementioned multiple coupling environments shall be concerned. It is necessary to establish hydrogen combustion environment experimental facility that closely simulates service conditions to conduct research on the impact of hydrogen-related environment on superalloys and their components. It is also essential to establish a mechanical performance database and standards for currently used key materials in hot section components such as turbine blades and disks for hydrogen related environments, and properly develop new high-temperature structural materials suitable for hydrogen combustion conditions, which will provide support for the application of hydrogen fueled gas turbine aero-engines.

Propeller propulsion technology plays an important role in aviation field. Composite materials have the characteristics of high specific strength, high specific modulus, high damping, designability and so on. The use of composite material propeller blades can further improve the performance of propeller in terms of mass reduction efficiency, propulsion efficiency, corrosion resistance, noise reduction. Composite material propeller blades have become the general trend. Based on aircraft propeller blades and rotor blades, this paper aims to perform a brief review of the research achievements of aviation composite propeller blades at home and abroad, classifies and expounds the material systems, structural design and molding processes of aviation propellers. The key technical problems and the simulation research on manufacturing process of propeller at home and abroad are summarized. Finally, the future development direction of domestic composite propellers from the aspects of improving the material system, optimizing the structure design, deepening the process research and strengthening the engineering application of numerical simulation technology are concluded.

Ultra-high strength aluminum alloy has achieved extensive application in the nuclear, aerospace, and aviation industries because of its high specific strength and low density. The fifth generation of ultra-high strength aluminum alloy has been produced, and in comparison to the fourth generation’s 600 MPa level, its ultimate strength has been consistently redefined and increased from 650-700 MPa to 750 MPa or even 800 MPa. This paper reviews the history of the research on aluminum alloys with ultra-high strengths and introduces the current state of development both domestically and internationally. The key issues and recent research development are further explored, including computer simulation, thermal deformation, heat treatment, homogenization, melting, and casting, as well as composition design. Finally, combined with the development needs of future equipment and domestic technology status, it is pointed out that in-depth study of basic theory to solve the problem of comprehensive performance matching, the promotion and application of special materials in specific application scenarios are the development trend and important direction of ultra-high strength aluminum alloy.

With the rapid development of low-temperature fields such as deep space exploration, polar scientific research, low-temperature storage and transportation, the service conditions for low-temperature structural components are becoming increasingly stringent. Therefore, low-temperature materials have gradually become a research hotspot in the world. This article mainly summarizes the low-temperature performance and related mechanisms of common structural materials such as low-temperature steel, aluminum alloy, titanium alloy, aluminum matrix composites and resin matrix composites. The effects of different crystal structures, alloy types, alloying elements and other factors on the mechanical properties of structural materials such as low temperature strength, plasticity and toughness, and the mechanism of low temperature deformation, strengthening and toughening are concluded. The application and prospect of different grades of low-temperature structural materials in different fields at home and abroad are also briefly introduced. The future research prospect of low-temperature materials is put forward.

Superalloys are predominantly employed to crucial aviation hot-end components such as turbine rear casings, diffusers, and pre-swirl nozzles. The investment casting technology supersedes “casting + welding” forming approaches, which reduces the number of parts and processing procedures, offers improved reliability and mass reduction. Therefore, investment casting is a pivotal technology for aviation component manufacturing. However, the casting of complex thin-walled components encounters challenges with dimensional accuracy, impacting engine aerodynamic performance and assembly precision, which has become a bottleneck problem restricting the manufacturing quality of key structural components of aero-engines in China for a long time. This article reviews the current advancement in the dimensional accuracy control for superalloy investment castings at home and abroad. A forward-looking analysis and discussion on development trends are conducted, particularly focusing on digital and intelligent technologies. There is an urgent need to build a digital twin platform for investment casting in the future and to develop more advanced accurate, quantitative and intelligent prediction methods for dimensional deformation and die profile design theory.

The current research status of refractory high-entropy alloys（RHEAs） is reviewed, the composition design of RHEAs is described, and the effects of metal elements and non-metal elements on the structure and properties of RHEAs are summarized. In addition, the microstructure and mechanical properties of RHEAs under different preparation methods are described, and the strengthening mechanism of RHEAs matrix composites is discussed. The future development of RHEAs is prospected, and the following suggestions are put forward for its future research direction: enhancing of RHEAs by multiphase synergistic effects through the interface design between different phases; designing and optimizing the composition of RHEAs to develop RHEAs that are easy to process at room temperature; quickly screening the composition and microstructure of RHEAs by combining with high-throughput calculation methods; regulating and controlling the microstructure and structure of RHEAs by additive manufacturing technology; carrying out the configuration design of RHEAs matrix composites to balance the strength and plasticity of RHEAs matrix composites.

Heterocyclic aramid refers to a type of para-aramid containing aromatic heterocycles（usually benzimidazole units） in the main chain, which has excellent properties of lightweight, high strength and modulus, high thermal resistance and good solvent resistance. Compared to the typical aramid fiber Ⅱ, heterocyclic aramid exhibits superior mechanical properties and has been practically applied in the fields such as aerospace and bulletproof protection in China. However, similar to other organic fibers, the composite performance of heterocyclic aramids with resins is relatively low due to their inert surface, which limits their application in the field of advanced composite materials. This article from two aspects of surface modification and structural design, the design ideas, technical means and research results to enhance the composite performance of heterocyclic aramids in recent years are summarized, and the development trend of its application in the field of advanced composite materials is forecast, so as to provide assistance and reference for the interface design and improvement of interfacial adhesion of organic fibers.

With the improvement of thrust-to-weight ratio and other properties of future aero-engine, the high temperature mechanical property and structural stability of titanium alloy components are required. The limitation of traditional experiments in time and space scale has become increasingly prominent, and it is difficult to deeply study the microscopic transient phenomena and mechanisms. Moreover, the molecular dynamics（MD）calculation method takes the atomic/molecular model as the calculation object, on the basis of Newton classical mechanics and empirical parameters, the calculation efficiency is greatly improved compared with the quantum calculation method. Therefore, MD has become an important method to optimize the process parameters and calculate the microstructure properties of aero-engine titanium alloy. Based on an overview of the basic principle of MD computing space and time scale advantages, this paper reviews the relevant domestic and foreign achievements in the study of molding, microstructure characterization and performance testing of aero-engine titanium alloys by MD method in recent years, as well as representative conclusions that contribute to the improvement of high temperature resistance of aero-engine titanium alloys. Finally, the future prospect is discussed based on the demand for MD computing technology for aircraft engine titanium alloys, thus pointing out the challenges faced on the following aspects, including high-throughput composition design based on MD computing method, training molecular force fields for mature titanium alloy systems, and introducing the new ReaxFF（Reactive Force Field）into the study of combustion mechanisms.

Additive manufacturing provides a new way to develop high-performance superalloys and components. A γ′- strengthened CoNi-base superalloy suitable for additive manufacturing was developed, and a crack-free block material was prepared by optimizing the parameters of electron beam melting（EBM） technology. The experimental results show that the lowest porosity of the alloy is about 0.14% when the scanning speed is 2000 mm/s. The microstructures of the as-printed CoNi-base alloy are columnar grains growing along the <001> direction, the average grain width is about 235 μm, and the volume fraction of γ′ phase is about 30%. After hot isostatic pressing and solution aging treatment, the porosity of the alloy is further reduced to about 0.09% with unobvious change of columnar grains. The average size of γ′ phases is about （70±18）nm with the volume fraction of about （32±3.6）%. The results of room temperature tensile tests show that the additive manufactured γʹ-strengthened CoNi-base superalloy exhibits excellent strength and ductility, showing a good potential of industrial application.

The precipitation behavior of secondary α phase and mechanical properties of high strength TB9 titanium alloy were investigated during single aging and duplex aging. The alloy phase constitution was analyzed by XRD, and the microstructure was observed by optical microscopy and scanning electron microscopy. The evolution characteristics of the microstructure with aging temperature were mainly analyzed. The room temperature tensile properties and fracture toughness were tested. The research results indicate that during single aging, secondary α phase exhibits serrated and layered precipitation. With increasing aging temperature, the size of α phase increases, and the content of layered α phase increases. The strength at 430 ℃ aging is lower and the plasticity is higher. The strength at 470 ℃ aging is the highest. With increasing aging temperature, the strength first increases and then maintains at the similar level. During duplex aging, most of secondary α phases precipitate in a serrated shape within the grains. With increasing aging temperature, the size of α phase increases, the tensile strength first increases and then decreases, reaching a maximum of 1542 MPa. The tensile strength of duplex aging is significantly higher than that of single aging, which is mainly due to the combined strengthening effect of second phases near grain boundaries and intragranular α phases with serrated shape.

The miniaturization and lightweight development of aerospace systems have raised higher requirements for the strength and ductility of power shaft materials. In order to develop maraging steel with the strength exceeded 3 GPa, an experimental maraging steel with high contents of Co, Ni, and Mo elements was designed. Its chemical composition is 4Ni-15Co-9Mo-0.86Ti-0.35Al-Fe. Through the high-temperature and large-scale plastic deformation with forging ratio greater than 10, the grains were refined as much as possible. Combining with pre-stretching deformation and cryogenic treatment followed by aging treatment, the tensile strength of the experimental steel reached 3.076 GPa, with the elongation at break of 5.5%, exhibiting excellent strength and plasticity. The analysis and characterization of the microstructures indicated that the lath martensitic microstructure with high dislocation was formed in the experimental steel, and obtained extra fined grains with the average grain diameter of 0.47 μm. TEM and 3DAP results show that a large number of Ni₃（Mo, Ti）precipitates is distributed in the matrix, with the average precipitate diameter of 6-7 nm. Precipitation strengthening, grain refinement strengthening and dislocation strengthening are the main strengthening mechanisms, which ensure an ultrahigh strength over 3 GPa of the experimental steel, while the extremely fine submicron grains also ensure the good ductility of the steel.

In view of the shortage of conventional design methods of pressure curve in the anti-gravity precision casting and taking the structural characteristics of the casting with variable cross-sections into account, automatic calculation of cross-sectional areas was implemented for the casting and gating system by the secondary development of CAD software, and quantitatively describing the variable feature of cross-sections of casting was realized. Based on Bernoulli and flow conservation equations, the relationship between the filling pressure and the rising speed of metal liquid level was deduced. A new design method of pressure curve based on the automatic calculation of cross-sectional areas of the casting was proposed. The simulation results of anti-gravity casting for nickel-based superalloy demonstrate that, compared with the pressure curve of the conventional design method, the new curve can reduce the peak value of filling speed from 0.611 m/s to 0.439 m/s at the minimum cross-sectional area, the falling range of which is 28.15%. It meant that the new method can effectively avoid the shock and splash of liquid metal, meanwhile, shorten the filling time, then the filling process is fast and stable. The hydraulic experiment and pouring experiment show that the new pressure curve has a smoother filling liquid level and can effectively avoid casting defects. Therefore, it proves the effectiveness of the new pressure curve design method and provides a basis for rational design of anti-gravity pressure curve.

The room temperature tensile properties and elevated temperature tensile properties of peak aged Al-Cu-Mg-Ag hub forgings after different heat exposure temperatures and heat exposure time were tested, and the thermal stabilities of the forgings at different temperatures were compared and analyzed. The results show that Al-Cu-Mg-Ag forgings exhibit good thermal stability. After exposure at 150 ℃ for 1 to 100 h, there were no significant changes in room temperature tensile properties and elevated temperature tensile properties. Short time heat exposure at 150-200 ℃ for 1 h does not reduce the overall performance, but the strength of Al-Cu-Mg-Ag forgings decreases with the increase of heat exposure temperature and the extension of heat exposure time. After 100 h of exposure at 200 ℃ and 250 ℃, the room temperature yield strength remains 61.1% and 37.2 %, and the room temperature tensile strength remains 77.8% and 60.8%, the elevated temperature yield strength remains 61.6% and 42.8%, and the elevated temperature tensile strength remains 67.5% and 47.6%, respectively. The main precipitates of Al-Cu-Mg-Ag forgings are Ω phase and θ′ phase. Under the experimental conditions of K_t=1 and R=0.1, the room temperature fatigue limit after 200 ℃/10 h heat exposure is 278 MPa, which is 10.6% lower than the fatigue limit of 311 MPa before heat exposure.

High strength Ti-5Al-3Mo-3V-2Zr-2Cr-1Nb-1Fe（Ti-5321） alloy is a new type of high strength tolerance titanium alloy designed and developed to meet the demand of high performance titanium alloy for new generation aircraft in China. Ti-5321 alloy with equiaxed microstructure（EM）, basket-weave microstructure（BW） and fine basket-weave microstructure（F-BW）was obtained by forging and heat treatment, and the tensile properties and fatigue crack growth behavior were studied. Fatigue crack propagation mechanisms in Paris and unstable propagation regimes were revealed by analyzing the microstructures and fracture morphology using optical microscopy (OM) and scanning electron microscopy (SEM). The results show that the samples with EM, BW and F-BW exhibit the excellent fatigue crack propagation resistance with the tensile strength of 1200 MPa. The sample with F-BW presents the highest fatigue crack propagation resistance in Paris and rapid growth regimes, while the sample with EM presents the lowest fatigue crack propagation resistance. In F-BW, the crack mainly propagates through and along α phase. Crack tends to propagate across colony oriented for （$ \bar{1} 011$）<$ {1}2\bar10 $> pyramidal slip and propagates along colony oriented for （$10 \bar{1} 0$）<$1 \bar{2} 10$> prismatic planes.

The AlSi10Mg alloy samples were successfully prepared by laser powder bed fusion（LPBF）. The effects of three kinds of heat treatment process, namely 130 ℃/4 h aging treatment, 236 ℃/10 h annealing treatment, and 540 ℃/1 h solid solution treatment on the microstructure of the AlSi10Mg samples were investigated. After heat treatment, the evolution of coefficient of thermal expansion（CTE） and thermal conductivity of the AlSi10Mg alloy in the temperature range from room temperature to 400 ℃ was examined. The results show that spherical Si particles are precipitated within the aluminum matrix, while the complete network-like eutectic silicon structure is retained after aging treatment. After annealing, the network-like silicon structure is disappeared completely, and spherical Si particles are uniformly distributed within the matrix. After solution treatment, large blocky Si particles with the sizes from 1 μm to 3 μm appear. The thermal properties of the AlSi10Mg alloy have been improved significantly after heat treatment compared to the as-printed state. In particular, the CTE of alloy subjected to annealing is 1.64×10⁻⁵ ℃⁻¹ to 2.1×10⁻⁵ ℃⁻¹ within the temperature range from room temperature to 400 ℃, the average thermal conductivity is 179.6 W·m⁻¹·K⁻¹, the performance is superior to ageing and solution treatments.

The high temperature deformation behavior of vacuum powder forging FGH95 alloy was studied by Gleeble-3800 thermal simulation testing machine. The hot compression test was carried out at the deformation temperature of 1090-1170 ℃ and the strain rate of 0.01-10 s⁻¹. The flow stress-strain curves under the corresponding conditions were obtained. The effects of deformation conditions on the microstructure evolution of vacuum powder forging FGH95 alloy were analyzed by EBSD. After considering the influence of temperature, strain rate and strain on the flow behavior of the alloy, the Arrhenius equation was selected to establish the constitutive model of vacuum powder forging FGH95 alloy, and the parameters of vacuum powder forging FGH95 alloy were obtained. The relationship between material parameters and strain was fitted and the obtained constitutive equation was verified.The results show that the flow stress of FGH95 alloy prepared by vacuum powder forging process decreases with the increase of temperature and increases with the increase of strain rate. The size of recrystallized grains in the deformed microstructure decreases with the increase of temperature and increases with the decrease of strain rate. The error between the predicted value and the experimental value of the flow stress of the vacuum powder forging FGH95 alloy is 6.33%, and the predicted value is in good agreement with the experimental value.

Flaw tolerance performance of TC4 alloy was investigated for helicopter transmission systems design. The impact pit flaws and scratch flaws were investigated by fatigue specimens with same flaw depth for flaw tolerance design, and high-cycle fatigue S-N curve tests were conducted. The results show that both scratch flaws and impact pit flaws significantly reduce the fatigue limit of the TC4 titanium alloy. The scratch flaw has a higher flaw influence factor（K_flaw） of 2.29 compared to the impact pit flaw’s K_flaw value of 1.75 under the same flaw depth conditions. Fracture surface analysis provided laws of the fatigue crack initiation and propagation associated with these flaws. Scratch flaws mainly exhibit multiple sources, with crack initiated at the root of the scratch, while the characteristics of fatigue crack initiation for impact pit flaws vary with the applied stress. Multiple sources are observed under high stress lever, with crack initiated on the surface of the pit, while under low stress, the crack initiates at a subsurface of the pit.

High Mach flight has put forward more stringent requirements for the material and structure design of new generation of high-speed vehicles. This paper reviews the application of ceramic matrix composites（CMCs） in the structural design of aircraft from the aspects of selection, application, and evaluation, and then the future development direction is put forward to provide reference for aircraft ceramic matrix composite structure design. The selection criteria and corresponding preparation methods of CMCs in different application scenarios are comprehensively reviewed, the typical applications of CMCs in aircraft structures are systematically introduced, and the evaluation criteria and ground test methods of the materials under near-service conditions are analyzed. To order to meet the future demands of aircraft, it is necessary to integrate computer-aided optimization technology and innovative preparation methods to enhance the temperature resistance and fatigue performance of CMCs. Developing highly reliable, long-life joining techniques and integrated design solutions will fully leverage the advantages of these materials. Additionally, in-situ characterization techniques under multi-physical field coupling need to be developed to obtain the performance evolution behaviour of CMCs in actual use, providing a reliable basis for the lightweight structural design of aircraft.

Radiation environments such as galactic cosmic rays, solar cosmic rays and radiation belts produce various space radiation effects on the components and astronauts, threaten the normal operation of spacecraft and life and health of astronauts. Material shielding is currently one of the most effective radiation protection measures and plays an important role in ensuring the smooth progress of aerospace missions. The research progress of space radiation shielding materials in different scenarios for three typical objects: components, astronauts, and aircraft platform protection is reviewed in this paper. Also the development direction of space radiation shielding materials such as metal composite materials and polymer materials is explored.

This paper explores the application and development trends of artificial intelligence (AI) technology, particularly machine learning and natural language processing in the field of failure analysis. Failure analysis is a crucial method for ensuring the reliability and safety of equipment, and is widely used in aerospace, automotive manufacturing, electronic devices, and other fields. Traditional failure analysis methods often rely on expert experience, which is time-consuming and laborious. By integrating AI’s powerful data processing capabilities with traditional methods, the accuracy and efficiency of analysis have been significantly enhanced. In terms of failure mode diagnosis, AI can rapidly and accurately identify various fault modes and provide precise diagnostic results. In failure cause diagnosis, AI integrates data from multiple sources to uncover complex failure factors and potential causal relationships, improving diagnostic reliability. In failure prediction, machine learning can accurately forecast material lifespan and strength, reducing experimental time and costs. In failure prevention, AI offers new approaches to effectively reduce the risk of failure and lower product maintenance costs. The paper also looks forward the future development prospects of AI in failure analysis and highlights challenges and recommendations in the areas, such as data quality improvement, model optimization, interdisciplinary collaboration, and ethical and safety issues.

The aircraft engine is considered the “heart” of the aircraft. The development of advanced aircraft engines focuses on achieving a high thrust-to-weight ratio, high efficiency, low fuel consumption, and extended operational life. High-temperature functional coatings, such as thermal barrier coatings（TBCs）, thermal/environmental barrier composite coatings（T/EBCs）, and high-temperature stealth coatings, are applied to critical hot-end components of aircraft engines. These coatings play a significant role in enhancing the service performance, operational life, safety and reliability of the engine. Taking TBCs, T/EBCs, and high-temperature stealth coatings as examples, this paper provides a systematic overview of recent research progress in the design of high-temperature functional coating materials, coating preparation science and technology, and coating performance evaluation and characterization, both domestically and internationally, with a specific focus on the advancements made at Beihang University. Furthermore, challenges and development trends faced by new high-temperature functional coatings of advanced aircraft engines in the future are also discussed. In the future, the research focus of advanced high-temperature functional coatings will shift toward multifunctional composite coatings, enhanced adaptability to extreme environments, and improved process compatibility.

With the global energy transition and increasing environmental requirements, hydrogen-mixed gas turbines as a high-efficiency and low-emission energy conversion equipment has been widely concerned. This paper reviews the development status of hydrogen-mixed gas turbines domestically and internationally, analyzes the characteristics of hydrogen combustion in gas turbines, explores the impact of hydrogen combustion on complex components and the application of high-temperature materials, and analyzes the performance requirements for hot-end component materials operating under high temperature, high pressure, and corrosive conditions, as well as the main challenges and potential solutions in current material development. The effects of water vapor and hydrogen embrittlement during hydrogen combustion on gas turbine alloys and thermal barrier coatings are discussed in detail.Water vapor accelerates the oxidation and corrosion of alloys, leading to a decline in mechanical properties. Furthermore, hydrogen embrittlement significantly affects the toughness and durability of alloys, increasing the risk of crack propagation and fracture. In terms of the problems, future research should focus on multi-field coupling simulations and accelerated corrosion tests, considering the factors such as temperature, pressure, and different atmospheres to establish realistic environment simulators to evaluate alloy and coating performances. Additionally, the combined effects of hydrogen and water vapor on high-temperature alloys and thermal barrier coatings should be emphasized. This includes investigating the diffusion mechanisms of hydrogen in alloys, interactions with lattice defects, and the microscopic processes leading to hydrogen embrittlement. Building oxidation models in high-temperature water vapor environments, clarifying the dissociation and adsorption mechanisms of water vapor at high temperatures, the hydroxylation of protective oxide films Al₂O₃ and Cr₂O₃, and the growth behavior of non-protective oxides（e.g., spinel） are also essential.

High-entropy alloys（HEAs）have attracted considerable attention from the research community as a pioneering alloy design paradigm over the past two decades. They have fundamentally challenged traditional design paradigms and exhibited exceptional mechanical properties and functional characteristics, thereby positioning themselves as promising candidates for significant engineering applications in the future. Recent advancements have unveiled several alloy systems that demonstrate exceptional performance across diverse metrics, including low-temperature fracture toughness, high-temperature strength, impact resistance, radiation tolerance, and fatigue resistance. These qualities render HEAs highly attractive materials for research with substantial application potential in critical domains such as deep space exploration, deep-sea investigations, low-temperature superconductivity, and advanced nuclear energy technologies. This paper will briefly introduce the concept and classification of HEAs, and review the experimental progress of HEAs under various extreme conditions such as extremely low temperatures, high-speed impacts, and high nuclear radiation. We also summarize the strategies for enhancing the strength and toughness of HEAs, and extract the deformation mechanisms and physical and chemical properties of HEAs under different extreme loads. It is foreseeable that the main development direction of HEAs will be to form microscopic fluctuations in chemical composition and construct multi-scalestructural ordering efficiently through fine adjustment of the selection and proportion of alloying elements and optimization of heat treatment processes. For comprehensive studies on HEAs subjected to extreme loads, it is essential to explore their microscopic deformation mechanisms further while proposing innovative strategies designed to address inherent trade-offs between strength and toughness. The integration of state-of-the-art simulation techniques combined with advanced characterization methods will be crucial for improving research efficiency while providing insights into microstructural behavior. Additionally, tailored optimization approaches should be implemented for distinct advantageous systems and phase structures, particularly those capable of activating dislocation movements, twinning, phase transformations and incorporating novel processing methodologies such as additive manufacturing. Finally, conducting more realistic simulation experiments that closely replicate extreme environments along with generating relevant engineering data are vital steps toward accelerating the practical application of HEAs in challenging settings.

The development of supersonic aircraft has created an urgent demand for heat-resistant aluminum alloy that can serve at the temperatures range from 300 ℃ to 500 ℃. However, the high-temperature mechanical properties of heat-resistant aluminum alloys are still unable to meet practical application requirements. Therefore, further research is needed from the aspects of material composition design and microstructure control to improve the comprehensive mechanical properties of heat-resistant aluminum alloys. In this paper, the research progress of heat-resistant aluminum alloys is reviewed from the aspects of microalloying design and eutectic alloys, and the development trend of heat-resistant aluminum alloys is prospected. The article first systematically introduces the development history and research status of Al-Sc, Al-Cu, Al-Si, and Al-Mg heat-resistant aluminum alloys, focusing on the microalloying design ideas of heat-resistant aluminum alloys, as well as the effects of transition metal elements and rare earth elements on precipitation phases, microstructure, and mechanical properties. Subsequently, the development status of heat-resistant eutectic aluminum alloys in Al-Fe, Al-Ni, Al-Ce, and Al-Si systems is comprehensively summarized, with a focus on the important role of rapid solidification technology and additive manufacturing technology in promoting the development of heat-resistant eutectic aluminum alloys. Finally, the main problems faced in the development and application of new heat-resistant aluminum alloys are analyzed, and the development trends of future research on heat-resistant aluminum alloy is discussed from the perspectives of data-driven composition design, high-throughput experimental verification, engineering application research, and standard system construction.

As the turbine inlet temperatures of aero engines continue to rise, there is an urgent need to develop a new generation of single-crystal superalloys and their thermal protective coatings for turbine blades. In order to meet the stringent requirements for the comprehensive performance of high-temperature structural materials in the complex service environments of aero engines, the intelligent design research of single crystal superalloys and thermal protection coatings has been gradually carried out at home and abroad in recent years under the promotion of material integrated computational engineering and material informatics. This paper reviews the latest research progress in the design of novel single-crystal superalloys and thermal protective coatings by utilizing multi-scale computational simulations and machine learning methods. The findings confirm that multi-scale computational simulations offer robust theoretical support for understanding the strengthening and toughening mechanisms of single-crystal superalloys, as well as the oxidation resistance and diffusion protective mechanisms of thermal protective coatings. Additionally, the study highlights the reliability and significant potential of machine learning in constructing intrinsic "composition-structure-property" relationship for high-temperature structural materials. This approach paves an intelligent and efficient new pathway for the rapid development of next-generation high-temperature single-crystal superalloys and thermal protective coatings.

Silicon carbide fiber-reinforced silicon carbide ceramic matrix composites（SiC_f/SiC） used in aero-engines are damaged or even failed due to the oxidation and corrosion by high-temperature and high-speed combustion gases. In this work, the gas generation device was used to simulate the complex gas environment in the aircraft engine, and the aviation kerosene mixed with liquid oxygen fuel in a certain proportion was ignited to form a high-temperature and high-speed combustion gas to assess the material. The oxidation test for 10 h and thermal shock test for 1000 cycles in combustion gas environment at 1200 ℃ were conducted on SiC_f/SiC composites respectively. And the protective effect of environmental barrier coating（EBC）on SiC_f/SiC composites was investigated. Uniaxial tensile tests were conducted on SiC_f/SiC composites and SiC_f/SiC-EBC composites after combustion gas environment assessment, and their fracture and cross-section micro-morphologies were observed by scanning electron microscopy. The results show that no significant oxidation of fibers and interphases is found in SiC_f/SiC composites and SiC_f/SiC-EBC composites after oxidation for 10 h in combustion gas environment, and their uniaxial tensile strength decreases by less than 2%. After 1000 thermal shock cycles in combustion gas environment, multiple micro-cracks are formed and oxidative corrosion of the interfacial layer occurs inside the SiC_f/SiC composites, and the uniaxial tensile strength decreases by 41.3%. The EBC coating can effectively protect the SiC_f/SiC composites from oxidation and corrosion of high-temperature gas, and the uniaxial tensile strength of SiC_f/SiC-EBC composites decreases by 16.6% after 1000 thermal shock cycles.

The types, preparation methods, thermal and mechanical properties of rare earth hafnate materials and their corrosion behaviors exposed to low melting point silicate（CMAS） and high temperature water vapor are summarized. The previous investigations indicate that the rare earth hafnates have the characteristics of low thermal conductivity, excellent high-temperature phase stability and good resistance to CMAS corrosion, which shows a favorable application prospect in the field of thermal/environmental barrier coatings（T/EBCs）. However, in order to overcome the limitations of a single-phase rare earth hafnate exposed to water vapor corrosion and CMAS, it is still necessary to carry out systematic studies on multi-rare earth components/high-entropy rare earth hafnate in the future, and further clarify the mechanism of influence of lattice distortion caused by components on physical and chemical properties of materials. Moreover, the coupled control method of thermal, mechanical and chemical properties of hafnate with integrated functions such as thermal protection, water vapor corrosion resistance and CMAS resistance and their corresponding material preparation processes should be explored.

Magnesium alloy is widely used in the aerospace field due to its low density, high specific strength, high damping and good thermal conductivity. However, its low elastic modulus limits its reliable application in large thin-walled components. Aiming at the problem to improve the modulus properties of magnesium-based materials, this paper briefly introduces the main factors affecting the modulus of the alloy, compares the advantages, disadvantages and application scope of relevant calculation models such as equal stress-strain model, rule of mixture, Halpin-Tsai model and two-phase composite model, summarizes the current situation and progress of the research on the modulus properties of magnesium-based materials, and reviews the two major ways of modulus improvement of magnesium-based materials and the mechanism of performance improvement. Based on the integrated computational material engineering, the integrated development strategy of high-strength and high-modulus magnesium-based materials for atomic-lattice scale analogy high-modulus aluminum alloy development and machine learning assisted optimization experimental design is proposed.

Ceramic fiber sponge with low density, high specific surface area, high porosity, good thermal stability and good thermal insulation performance is expected to become one of the most promising commercial ceramic materials in the fields of heat insulation, flame retardant, water-oil absorption and energy conversion. This paper summarizes the direct assembly methods such as three-dimensional electrospinning, solution blowing spinning and centrifugal spinning, reviews the research progress in the production of ceramic fiber sponge by direct spinning method, analyses the problems of low production efficiency of ceramic fiber sponge, and proposes the future development directions of ceramic fiber sponge: （1）improve the production efficiency, reduce the production cost, and mass produce ceramic fibre sponge with controllable shape; （2）improve the high-temperature thermal insulation performance and promote the application of ceramic fibre sponge in the field of heat insulation; （3）improve the structural stability and produce ceramic fibre sponge with high elasticity, flexibility, and fatigue resistance; （4）research and develop ceramic fibre sponge materials with special functions such as light and electromagnetism, and expand the application range of ceramic fibre sponge.

The manufacturing process of composites is crucial for ensuring structural efficiency and application reliability of their products. Computer-based process simulation plays a significant role in improving the manufacturing quality of composite components and reducing the manufacturing cost. Traditional process simulation relies on physical and chemical mechanisms in manufacturing of composites with the mathematical equations solved by numerical methods such as finite element/finite volume analysis and computer-aided design methods e.g. computer graphics. At present, it has been widely used in simulations of the lay-up of reinforcements/prepregs, the infiltration flows of resin, the curing behaviours of thermosetting resin, the heat transmission and exchange, and the nonlinear mechanics including residual stress and curing deformation predictions. Recently, artificial intelligence（AI）technologies have rapidly developed, its technical basis machine learning（ML）, in combination with artificial neural networks（ANN）, has been used in the field of lay-up process of fiber reinforcements, liquid molding processes, and autoclave processes, which aimed for data mining and developing reduced-order models. The former can establish relationships between process conditions and the curing quality or mechanical properties of the composite parts, while the latter can improve computational efficiency of the process simulation. However, due to the complexity, immeasurability, and high cost of manufacturing fiber-reinforced resin matrix composites, at the beginning of the AI age, it is difficult to meet the requirements of ML only by relying on the amount of data obtained by experiments. Also, data-driven AI technology faces uncertain issues regarding the representativeness, generalisability, and interpretability of the models. Therefore, traditional process simulation based on physicochemical mechanisms can provide a large amount of reliable data for data-driven ML simulation, and then through AI, more quantitative models describing the composite process can be established to expand the computable scope of process simulation. At the same time, as AI technology enhances the computational efficiency, the process simulation that meets real-time requirements can evolve into digital twins（DT）of the composite manufacturing process, which can provide new technical support for reducing the composite costs and improving the scientific whole-life cycle management.

Thermoelectric materials can efficiently and cleanly convert between electrical and thermal energy, offering significant prospects in waste heat recovery and electronic cooling applications. Lead telluride（PbTe）materials were used in thermoelectric power sources for deep space exploration. Lead selenide（PbSe）, a homologue of PbTe, shows potential as a more abundant and cost-effective alternative for mid-temperature thermoelectric power generation. Recently, research in PbSe thermoelectric has shifted from mid-temperature power generation to near-room-temperature cooling, driven by the growing demand for Te-free thermoelectric cooling materials and devices. This paper reviewed the typical optimization strategies used in the research of p-type PbSe, summarized the key research progress in thermoelectric devices based on this material, and highlighted its significant development prospects. Finally, we provide a personal outlook on developing the near-room-temperature thermoelectric performance of p-type PbSe materials and manufacturing high-performance cooling devices, which includes integrating various optimization strategies, optimizing device assembly techniques, identifying suitable contact materials, and developing Te-free thermoelectric devices based on PbSe, with the goal of advancing their application in critical fields such as deep space exploration and laser cooling.

The dovetail of ceramic matrix composites（CMC）turbine blade is the key to the assembly and ability to withstand centrifugal loads of the blade. In order to study the mechanical behaviour of the blade dovetail prepared by the melt infiltration（MI）method under the tensile load in the radial direction of rotating, and verify the influence of the internal quality of the dovetail on its static tensile strength and failure mode, the CMC high pressure turbine dovetail element specimens were designed and fabricated, and a uniaxial static tensile test was conducted, the internal quality of the test specimens was scanned using non-destructive X-ray CT. The test process was monitored using DIC and acoustic emission method. The results show that the CMC dovetail is able to maintain in complete contact under uniaxial static tensile loads, and its static strength and failure are very sensitive to its internal quality, especially to the delamination defects. When there are no delamination defects in the dovetail, the damage generally starts from the neck and quickly spreads, the damage starting load is near the maximum fracture load, and the fracture surface is zigzag. When there are delamination defects in the dovetail, the fracture starts from the defects, and the delamination gradually spread and cause the fracture surface of the dovetail, the damage starting load is decreased by 99.05%, and the maximum failure load is decreased by 14.29% compared to the case of no delamination defects, and the fracture surface is consistent with the delamination defects.

The spot-welding defects of highly alloyed Ni-base superalloy GH4065A were investigated by using SEM and EBSD analysis methods. Effects of the welding defects on fatigue life and fracture behavior were studied by comparing thin plate samples with a central hole that were non-welded, densely welded and sparsely welded respectively. The results show that the lack-of-fusion defect, solidification crack and liquation crack are the main welding defects responsible for significant reductions in low-cycle fatigue life as well as combined low and high cycle fatigue life. These welding defects result in a transition of the fatigue crack initiation site from the inner surface of the central hole in the non-welded sample to the welding spot in the welded sample, leading to 44%-83% reductions in low-cycle fatigue life at 700 ℃/700 MPa. For the combined low and high cycle fatigue conditions（with a stress amplitude of 700 MPa for the low cycle loading part and 100 MPa for the high cycle loading part）, the welding defects not only alter the site at which fatigue cracks initiate, but also make the crack propagation mode more intergranular. This results in dramatic decreases of over 85% in the fatigue life of welded samples at both 600 ℃ and 700 ℃. Due to shorter distance between the welding spot and the central hole, densely-welded samples exhibit a slightly lower level of fatigue life under low-cycle loading conditions compared to sparsely welded samples. However, the fatigue life difference between them becomes negligible when subjected to combined low and high cycle loadings.

The Si/Mullite+BSAS/Yb₂Si₂O₇ tri-layer environmental barrier coating was prepared on the surface of the SiC substrate by atmospheric plasma spraying using solid-state sintering Yb₂Si₂O₇ feedstock. Scanning electron microscope （SEM）, energy dispersive spectrometer （EDS）, X-ray diffraction analyzer （XRD） and nanoindentation testing machine etc were employed to study the microstructure, phase composition, and mechanical properties of the coating. The results indicate that the powder is composed of 83% Yb₂Si₂O₇ phase and 17% Yb₂Si₂O₇ phase, the porosity of the Yb₂Si₂O₇ layer obtained by plasma spraying is （6.61±0.65）%, the bonding strength of the coating is （22.82±3.55）MPa and the fracture toughness of the coating is （1.98±0.12）MPa·m^1/2. Furthermore, the water-oxygen corrosion test results of the coating at 1350 ℃ show that the monoclinic phase contents of the Yb₂Si₂O₇ phase decrease first and then increase. The thermally grown oxide SiO₂ formed by high-temperature oxidation of the silicon bonding layer is compatible with Mullite+BSAS, and interdiffusion between Mullite+BSAS and Yb₂Si₂O₇ layers isn’t detected. Deterioration of the silicon layer is a major limiting factor in the lifetime of the coating.

With the advancement of space laser technology, laser systems are progressing towards shorter wavelengths, longer lifetimes, and higher orbits. It requires higher performance coatings that can withstand the damage caused by the harsh space environment, such as vacuum, high and low temperatures, proton radiation and Gamma-ray radiation. This paper reviews the development direction of the main space lasers at home and abroad. It also discusses the effects of the space environment on coatings during the development of space laser systems and the evolution mechanism of coating performance under service conditions. It presents the new advances in high-performance space laser coatings and provides insights into future development directions, such as gravitational wave detection in space and deep space exploration.

SiC_f/SiC composites were prepared by melt infiltration（MI）process, chemical vapor infiltration combined with precursor infiltration and pyrolysis（CVI+PIP）process and precursor infiltration and pyrolysis（PIP）process, respectively. The microstructures, compositions and properties of SiC_f/SiC composites prepared by different processes before and after water-oxygen corrosion at 1300 ℃ were characterized by scanning electron microscopy and its accompanying EDS and X-ray diffractometer. The results show that the distributions of oxygen elements of the fracture surface is obviously different in the composites prepared by different processes, and the phases after corrosion are closely related to the preparation processes. The strength retention rate and modulus retention rate of SiC_f/SiC composites prepared by MI process are 84% and 76% after water oxygen corrosion at 1300 ℃ for 50 hours. The strength retention rate of SiC_f/SiC composites prepared by CVI+PIP is 64%, and the modulus is increased by 6%. The SiC_f/SiC composites prepared by PIP process has a strength retention rate of 49% and a modulus increase of 17%. The composite materials prepared by MI process show oxidation mass gain, while the composite materials prepared by CVI+PIP and PIP process show oxidation mass loss, which are mainly related to its microstructures and compositions.