The application of advanced composite materials in aeroengines has become one of the key technologies for improving engine performance, reducing mass and enhancing fuel efficiency. This article reviews the current status and development of advanced composite materials in foreign aero-turbofan engines, with a focus on the application of polymer composite PMC materials such as epoxy resin and polyimide, metal matrix composite MMC materials such as titanium alloy and aluminum alloy, and ceramic matrix composite (CMC) such as silicon carbide and aluminum oxide in engine components such as fan casings, low-pressure compressors, high-pressure compressors, high-pressure turbines, low-pressure turbines and nozzles. By analyzing the application and research and development progress of foreign aircraft engines in matrix, metal matrix and ceramic matrix composite, this paper explores their advantages in improving thrust to mass ratio and temperature resistance performance. At the same time, this article also looks forward to the future development direction of various composite materials in aeroengines, including the research and development of new composite materials, optimization of manufacturing processes, and potential applications and development trends of various composite materials in future aeroengines.

Technological innovation in high-performance damage-tolerant titanium alloys for aerospace equipment stands as a core strategic pillar, enabling China’s aviation industry to achieve independent design of equipment structures, localization of key technologies, and leapfrog industrial development. This paper conducts a comprehensive review of the research status and technological advancements in damage-tolerant titanium alloys for aeronautical structures both domestically and internationally, and focuses on expounding the research breakthroughs and engineering application achievements of new high-performance damage-tolerant titanium alloys for aircraft structures by Beijing Institute of Aeronautical Materials. The study proposes that adhering to the core of “demand-driven, systematic development, and cross-generation research and development” is the fundamental path to promote the iteration of China’s new-generation aeronautical high-performance titanium alloy material technologies. To this end, by making breakthroughs in key technologies such as precise alloy composition design, high-purity and clean smelting, homogenization forming of large-sized bars, integrated processing of integral forgings, and multi-scale comprehensive strengthening and toughening, a backbone material system of titanium alloys for Chinese aircraft structures with independent intellectual property rights has been initially established, covering three series of damage-tolerant titanium alloys: medium-high strength and high toughness, high strength and high toughness, and ultra-high strength and high toughness. Meanwhile, to meet the dual requirements of lightweight and cost-effective aeronautical structures, a new type of medium-high strength and high toughness, low-cost damage-tolerant titanium alloy and its application technology have been successfully developed. This development achieves the collaborative optimization of strength and toughness and the optimal performance matching of three typical microstructures of the alloy, providing a new approach for the lightweight design and engineering application of aeronautical structures. Future research should further integrate cutting-edge technologies such as artificial intelligence-assisted material design and additive manufacturing, strengthen basic theoretical research and engineering verification, and lay a solid theoretical foundation and provide technical support for the further enhancement of performance and wide-scale engineering application of high-performance damage-tolerant titanium alloy materials in China.

The operating temperatures of hot-section components in advanced aero-engines continue to increase, accompanied by increasingly severe service conditions. Conventional thermal barrier coatings（TBCs）can no longer meet these demanding requirements, necessitating the development of new TBCs with higher temperature resistance and superior overall performance. This paper systematically analyzes the application requirements for new thermal barrier coating materials in advanced aero-engines, focusing on material composition, fabrication processes and microstructure. It elaborates on recent research progress in three types of novel TBCs: rare-earth-doped ZrO₂ coatings applied via atmospheric plasma spraying（APS）, rare-earth zirconate coatings produced by electron beam physical vapor deposition（EB-PVD）, and high-entropy ceramic coatings fabricated through plasma spray-physical vapor deposition （PS-PVD）. Compared to traditional double-layer structured yttria-stabilized zirconia（YSZ） TBCs, these new coating systems—based on rare-earth-doped ZrO₂, rare-earth zirconates, or high-entropy ceramics—exhibit lower thermal conductivity, enhanced thermal shock resistance, and superior resistance to calcium-magnesium-alumino-silicate （CMAS） corrosion. Through in-depth integration with processes such as APS, EB-PVD and PS-PVD, the performance of these coatings has been significantly improved, making them suitable for application in critical hot-section components like floating wall tiles and turbine blades. As breakthroughs continue to emerge in new materials, structures and processes, these advanced thermal barrier coatings are poised to provide crucial support for next-generation aero-engines, enabling them to surpass current temperature limits and achieve greater efficiency and reliability.

Aerospace equipment materials demand an ultra-high level of safety and reliability, with fatigue performance being one of their core performance metrics. Traditional fatigue prediction methods rely heavily on extensive experimental tests, which are associated with high costs and long development cycles, thus failing to meet the requirements of modern aerospace engineering for efficient and accurate performance evaluation. In recent years, machine learning has exhibited remarkable potential in the fatigue life prediction of aerospace materials. This work presents a systematic review of the research progress in this field, with a focus on mainstream models and modeling workflows. It clarifies the core ideas and key research findings of both pure data-driven methods and physics-integrated approaches, and centers on the role of physical information embedding in enhancing model accuracy, credibility, and interpretability. Moreover, the paper critically discusses the existing limitations, including insufficient information mining in terms of data dimensions and complex failure mechanisms, inadequate model interpretability and low trustworthiness for engineering applications, as well as poor adaptability to complex service conditions. Finally, key research directions for addressing these limitations are highlighted, such as constructing standardized and highly reliable fatigue datasets, establishing a task-oriented automatic fusion mechanism for physical knowledge, and advancing fatigue life prediction at the level of structural components under complex service conditions.

Performance enhancement of advanced aero-engines sets a higher requirement for their overall structural lightweighting. Polymer-matrix composite (PMC) are one of the key materials to achieve aeroengine lightweighting. In recent years, focusing on the aero-engine cold-section parts, AECC Beijing Institute of Aeronautical Materials (BIAM) has systematically developed PMCs of high-toughness epoxy, high-temperature and high-toughness bismaleimide, high-temperature polyimide and high-toughness thermoplastic resins. This article introduces the foreign profile of PMCs for aero-engines and the demands of aeroengines for PMCs. Then, taking BIAM as the representative, domestic current status of PMCs for aero-engines and application are introduced. PMC development trend and emphasis for aero-engines are proposed. Overall, domestic PMC for aero-engines have made breakthrough in such aspects as high-temperature resistance, impact resistance, structure/function integration and integral fabrication technology, and have achieved batch application in such parts as fan blades, containment casings and outer ducts. For the needs of future aero-engines, PMC would focus more and more on the directions including thermal resistance enhancement, toughness improvement, structure integration, processing automation and intelligentization, full-life cost minimization.

Due to the sensitivity and complexity of the composition-process-microstructure-performance relationship, the research and development of high-performance titanium-based materials have long been constrained by the dual challenges of high-dimensional nonlinear optimization and high trial-and-error costs. As a highly pervasive disruptive technology, artificial intelligence (AI) is introducing a new research and development paradigm for the strategic field of high-performance titanium-based materials, shifting from experience-driven modes to dual-driven approaches supported by models and data. This review summarizes the latest research advances in artificial intelligence-enabled high-performance titanium-based material technology (AI+Ti), focusing on how AI provides innovative solutions targeting the inherent characteristics of high-performance titanium-based materials, including complex compositions, diverse phase transitions, narrow thermal processing windows, and strong path dependence of microstructure evolution. The main contents include breakthroughs achieved by AI in constructing high-precision phase diagram and performance prediction models, as well as realizing the inverse design from performance objectives to microstructures and further to composition and processing parameters; the intelligent upgrading from forming control to active regulation of microstructures and properties in key processes such as additive manufacturing and heat treatment; and the establishment of an in-service behavior prediction framework based on digital twins. On this basis, this paper further analyzes the core challenges in the AI+Ti field regarding data, models, verification and integration, and prospects future development directions such as physics-informed machine learning and autonomous experimental platforms. Finally, it discusses controversial issues involving knowledge representation, human-machine collaboration modes and engineering trust establishment, and elaborates on the future development trends of this field: (1) material performance prediction and multi-scale coupling under complex service environments; (2) intelligent coordination of full-process processing parameters; (3) the construction and iteration of specialized physics-informed perception models for titanium alloys. Beyond simple tool application, AI+Ti has evolved into a transformative revolution that enables in-depth understanding and ultimate mastery of the cognition and research paradigm for high-performance titanium-based materials.

Damage detection is a critical link of aviation equipment development, field operation and maintenance, which directly affects the development process and service safety of aircraft structure. In recent years, domestic and foreign scholars and scientific research institutions have carried out a lot of research works in the field of ultrasonic nondestructive testing. Based on this, this paper, guided by the needs of damage detection in the development and operation of aviation equipment, briefly analyzes the characteristics and requirements of typical structural damage of aviation equipment and in-situ detection. This paper focuses on summarizing the latest research progress of ultrasonic theories and methods, advanced detection sensor designs and special detection device research and development. Furthermore, incorporating new issues, ideas and directions emerging from technological research and engineering practice, this paper summarizes and forecasts the main challenges and future development trends in areas such as damage detection technologies for heterogeneous materials, transducer design methods for complex-shaped structures, and the equipment research and development and engineering application of new non-contact testing devices.

The design life of turbine blades in heavy-duty gas turbines (HDGT) typically reaches tens of thousands of hours, operating under conditions characterized by high stress, prolonged thermal exposure and coupled hot corrosion induced by complex media such as high salt and high sulfur. This paper systematically reviews the current research status and development trends of directionally solidified columnar (DS) and single crystal (SC) nickel-based superalloys for HDGT applications. Firstly, the graded material allocation strategy of “high performance for high-temperature front stages and cost-effectiveness for low-temperature rear stages” is clarified, noting that the core design logic has shifted from seeking instantaneous ultimate strength to ensuring long-term microstructural stability. Secondly, the evolution of alloy compositional design is emphasized, analyzing the “low-Re design philosophy” characterized by reduced Re content, optimized W/Mo ratios and increased Cr levels to suppress the precipitation of topologically close-packed (TCP) phases and enhance environmental resistance. Furthermore, considering the massive scale of HDGT blades, the challenges in manufacturing large-scale components are discussed, specifically the thermal-solute-stress multi-field synergistic instability induced by scale effects and the “microstructure inheritance effect” of dendritic segregation on service performance. Finally, this review elucidates the multi-mechanism coupled evolution of creep, fatigue and environmental damage under long-term service conditions, and highlights the prospective engineering applications of repair and life-extension technologies in life-cycle management. It emphasizes that the core of future development lies in reconstructing the surface protection systems of large-scale blades and efficiently restoring the degraded internal microstructures, without compromising the structural integrity of the original single crystal or directionally solidified substrates. It is pointed out that breaking through the bottleneck of casting yield for large-scale complex blades and improving hot corrosion resistance under extreme environments are the core challenges currently faced. Future research should focus on the synergistic optimization of mechanical-environmental performance and physics-based life prediction models to support the development of next-generation high-parameter gas turbines.

High-temperature resistant ceramic matrix composites (HT-CMCs) have demonstrated immense application potential in aerospace, energy, and other extreme service environments, thanks to their outstanding attributes such as exceptional high-temperature resistance, high strength, low density, and excellent chemical stability. Traditional manufacturing processes are constrained in fabricating HT-CMCs with complex shapes and high performance. In contrast, additive manufacturing (AM) technology has paved a new way for the production of HT-CMCs with intricate structures, leveraging its unique capability of layer-by-layer construction. This technology substantially improves the functional properties and structural efficiency of materials by enabling the direct fabrication of complex internal features, like cooling channels. It also supports performance-oriented precise control and customized production according to specific service requirements, while significantly reducing material waste and effectively cutting down manufacturing costs. This paper focuses on the additive manufacturing technology of HT-CMCs. It introduces the technical principles and current application status of this technology, and places particular emphasis on expounding the latest research advancements both domestically and internationally in material system design, forming technologies, and process optimization for additively manufactured HT-CMCs. Furthermore, this paper sets out the future trends of additive manufacturing for HT-CMCs. In terms of material-process synergy, the focus is on overcoming the bottleneck of interface bonding in multi-material printing and developing composite processes to achieve multi-functional integration and gradient structures. Regarding the construction of intelligent systems, the aim is to establish a “digital control-real-time monitoring-parameter optimization” system and reduce trial-and-error costs through AI-based parameter adjustment. In the realm of modularization and circular manufacturing, the emphasis is on developing interchangeable standardized modules and innovating ceramic waste recycling technologies to enhance material utilization rates. All these endeavors are aimed at promoting its engineering application in cutting-edge fields.

As a new type of high-temperature lightweight structural material, Ti₂AlNb alloy is regarded as one of the most promising candidates to replace nickel-based superalloys for significant weight reduction in critical high-temperature components of aero-engines. At present, the development of Ti₂AlNb alloy has reached a mature stage, and its application in aero-engines is accelerating. Therefore, the demand for transitioning the properties of the material from laboratory scale to actual structural service performance is becoming increasingly urgent. This paper systematically reviews the research status and development of the application performance of Ti₂AlNb alloy in aero-engines. Based on a summary of the development progress of the alloy, material selection analysis, and current application status in engines, the application pathway of “static components first, then rotating components” and its typical potential application objects are identified. Furthermore, the requirements and key research tasks for evaluating the structural application performance of Ti₂AlNb alloys are systematically outlined from the perspectives of engine structural integrity requirements, needs for strength and life analysis methods and tools, and the establishment of a comprehensive material application evaluation system. Subsequently, taking the combustor casing structure as an example, the current research status of the structural application performance evaluation of Ti₂AlNb alloys in aero-engines is elaborated in detail. Finally, based on the current research progress, future directions for advancing the material selection and structural application performance evaluation of Ti₂AlNb alloys are proposed: future efforts should focus on real engine service conditions, systematically conduct performance evaluations under multi-factor coupled environments, establish quantitative microstructure-property correlation models and develop material-structure-performance integrated design methods, so as to provide solid support for the engineering application of Ti₂AlNb alloys in critical components such as combustor casings.

Traditional ultrasonic automated non-destructive testing is a great challenge in the inspection of aviation components with complex surfaces. Complex surfaces can interfere with the formation of the focus in the sound beam, and the waveform transformation generated when the sound beam is incident is more complex. All these will lead to a decrease in the ultrasonic testing capability and a significant reduction in the obtained echo signal-to-noise ratio. Under the background of intelligent manufacturing, the development of rapid and low-cost manufacturing of aviation components has been seriously restricted. The paper analyzes the ultrasonic propagation of complex surface media, and summarizes the technical difficulties of automatic ultrasonic detection of complex surface components. The paper also describes the development status of three kinds of automatic ultrasonic imaging detection of complex surfaces, which are based on flexible phased array ultrasonic probe, ultrasonic C-scan imaging detection based on industrial robot and phased array ultrasonic imaging detection for complex surfaces. The advantages and limitations of three kinds of automated ultrasonic imaging detection are analyzed, and the challenges faced by various ultrasonic imaging technologies are reviewed. The key technology to break through the automatic ultrasonic imaging detection of complex aerospace components under the background of intelligent manufacturing is proposed. The paper introduces the future technical requirements for the development of advanced imaging algorithms for automated inspection and the intelligent recognition and classification of defects in the ultrasonic testing of complex aviation components. The key detection technologies based on digital twin detection path planning and the design and manufacture of massive channel phased array ultrasonic sensors, which are urgently needed to be broken through under the background of intelligent manufacturing, have been proposed.

The rapid progress in aerospace engineering places an urgent demand for advanced structural materials that exhibit outstanding mechanical properties under ultra-high temperature operating conditions. While recently developed refractory high-entropy alloys (RHEAs) hold promising application prospects, they are still confronted with challenges, including room-temperature brittleness and elemental segregation, which present significant hurdles in manufacturing processes. Additive manufacturing (AM) technology offers distinct advantages in fabricating RHEAs, such as suppressing elemental segregation, refining microstructures, and enabling the production of components with complex geometries, thereby revealing the substantial research potential. This paper firstly introduces the main technical methods for AM-fabricated RHEAs. Subsequently, it systematically summarizes their microstructural features, elemental distribution patterns, and phase composition characteristics, along with an overview of their mechanical performance at both room and elevated temperatures. To address critical process challenges, such as cracking and porosity in AM-produced RHEAs, we not only review recent research achievements but also propose innovative strategies that combine composition optimization and grain boundary engineering to enhance the AM process. Finally, this paper makes prospects for further enhancing the room-temperature plasticity and high-temperature strength by introducing grain boundary strengthening elements or high-entropy ceramic strengthening phases through additive manufacturing technology in the future, as well as for the preparation of large-sized RHEAs complex components by suppressing cracking and residual stress.

Thermal simulation compression tests are conducted on a new type of ultra-high strength and toughness TB17 titanium alloy using Gleeble-3500 thermal simulation testing machine under the conditions of deformation temperature ranging from 795 ℃ to 895 ℃ and strain rate of 0.001 s⁻¹ to 1.0 s⁻¹. The microstructure and plastic flow behavior of the alloy during hot deformation are analyzed, and a constitutive model of flow stress is established. The results show that the flow stress of the alloy increases rapidly with the increase of strain, then decreases slightly, and finally tends to be stable. Partial dynamic recrystallization occurs in the alloy, dominated by dynamic recovery, and the slight decrease in flow stress is related to the partial dynamic recrystallization of the alloy. Dynamic recrystallization volume fraction of the alloy is not higher than 40%, and the dynamic recrystallization mechanism is mainly dominated by the bowing mechanism. A constitutive model based on the Arrhenius equation is constructed, and the deformation activation energy Q value of the alloy at the temperature of 795-895 ℃ is obtained as 205.48 kJ/mol. The model has high prediction accuracy, with average error δ_avg of 3.987% and correlation coefficient R of 0.9972. The construction of this model provides an accurate prediction for the flow stress of TB17 titanium alloy during hot deformation and also offers a reference for the establishment of high-precision constitutive models for other alloys.

Single crystal superalloys exhibit excellent comprehensive properties and have been widely applied in advanced aero-engines. This paper reviews the development of single crystal superalloys from the aspects of strengthening mechanism and composition design, directional solidification and crystal growth, solid-state phase transformation and heat treatment and mechanical behaviour. Special emphasis is placed on the research progress of the high-performance, low-cost single crystal superalloys with independent intellectual property rights of China developed by Beijing Institute of Aeronautical Materials, and future development direction of single crystal superalloys are discussed.

Infrared thermal wave imaging detection technology has the advantages such as high efficiency, large detection area, and non-contact operation, making it widely used in the field of damage detection and evaluation of new materials in aviation and aerospace. This study introduces the principle, implementation approach and applicable conditions of typical infrared thermal wave imaging detection technology, covering various typical infrared thermal wave detection techniques such as pulse infrared thermal imaging, phase-locked infrared thermal imaging, frequency modulation thermal wave imaging, ultrasound assisted infrared thermal wave imaging, eddy current excitation infrared thermal wave imaging, and infrared thermal wave tomography imaging. In addition, the article also explores the current development status of infrared thermal wave non-destructive testing technology in the aerospace field, and lists practical application cases. Finally, this paper analyzes the main challenges faced by infrared thermal wave nondestructive testing technology and outlines its future development trends. The technology is evolving toward diversified excitation sources, intelligent detection, and deeper information integration: excitation sources will develop from single photothermal excitation to multi-physics collaborative excitation incorporating ultrasound, laser and electromagnetic methods; the detection process will integrate novel imaging technologies with artificial intelligence algorithms to achieve precise identification of subtle defects; information processing will leverage multi-source heterogeneous data fusion to overcome the limitations of single-technique approaches and enhance capabilities for quantitative defect detection and three-dimensional reconstruction.

Cast aluminum alloys are widely used in aerospace, automotive and other industries due to their excellent mechanical properties. However, traditional alloy design faces challenges such as vast composition space, high costs of trial-and-error experiments and difficulty in predicting the nonlinear relationship between composition and properties. This paper proposes a machine learning model that combines backpropagation neural networks, principal component analysis, and genetic algorithms for multi-objective property prediction of cast aluminum alloys. The model establishes the relationship between alloy composition and properties through the nonlinear mapping of backpropagation neural networks, reduces dimensionality via principal component analysis, and optimizes network parameters using genetic algorithms-thereby improving prediction accuracy and training efficiency. The results show that the optimized model has mean squared error of 36.28, correlation coefficient of 0.91, and mean absolute error of 2.44. In the experimental verification of ultimate strength, yield strength, and elongation after fracture, the error between experimental values and predicted values is controlled within the range of ±5%. This high prediction accuracy demonstrates the efficiency and reliability of the proposed model.

Materials and processes form the foundation of manufacturing development, especially for civil aviation products, whose design, verification and airworthiness certification are inseparable from the support of material data. Despite significant progress in domestic material and process technologies in recent years, material airworthiness certification of civil aero-engines still faces the challenges of insufficient verification data due to an incomplete material system and inadequate accumulation of historical data. The current primary contradiction is manifested as the conflict between the high requirements of civil aircraft airworthiness for materials/processes, the insufficient support capacity of the domestic material system, and the urgency of solving problems. This paper analyzes the core requirements of airworthiness regulations such as CCAR33.15 “Materials”, compares the current situation of domestic and foreign material/process airworthiness certification, and identifies gaps of China in material specification statistical validation, process control mechanisms, design allowable value generation and special processes. Combining practical issues in certification practice, a technology scheme based on national conditions is proposed. Relying on the national collaborative innovation mechanism, a five-dimensional implementation path of “Regulation interpretation-system collaboration-multi-party linkage-technical synergy-dynamic adaptation” is constructed. It promotes the improvement of enterprise material systems through type projects and accurately acquires verification data oriented toward design requirements. Practice shows that this scheme has promoted the completion of over 600 material and process tests, established more than 100 material specifications and over 1000 design performance curves, effectively supporting the type certification work. The research results provide technical references for improving the management of material/process airworthiness certification of civil aero-engines and promoting the application of independent materials.

2.5D woven composites show great promise for aerospace applications owing to their high specific strength, high specific modulus and good delamination resistance. However, there is a dearth of research on their mechanical properties and failure behaviour at high temperature environment. This paper presents numerical simulation and experimental study on the quasi-static tensile mechanical response and failure behaviour of 2.5D woven C_f/Al composites at high temperature (400 ℃). Representative unit-cell models at the micro- and meso-scale are constructed based on the microstructure and periodic arrangement characteristics of the yarn. Based on the temperature-related material parameters of the matrix and interface, a multiscale finite element model is established to numerically analyse the thermal stress distribution as well as macroscopic and mesoscopic mechanical behaviour of the composites at high-temperature environment. The high temperature induces inhomogeneous thermal stress distribution in the composites, where the matrix and yarns are subjected to compressive and tensile stress, respectively. The experimental results show that the tensile modulus, ultimate strength and elongation of the composites are 63.7 GPa, 238 MPa and 0.72%, respectively. The numerical tensile stress-strain curve is generally consistent with the experimental results. Numerical simulation results show that the matrix and interface damage that induced by the thermal stresses accumulates and expands gradually during the tensile process. This results in the emergence of local interface debonding at the initial tensile stage. As the tensile strain increases, the composites successively experience the local failure of warp yarns and transverse cracking of weft yarns. At the final stage, the severe axial fracture of warp yarns leads to catastrophic fracture of the composite, resulting in a dramatic drop of the tensile stress curve. The fractured warp yarn exhibits a rough fracture surface with the characteristics of fibre pull-out and matrix alloy tearing.

TiAl alloys have advantages such as low density and excellent high-temperature mechanical properties. They can replace nickel-based superalloys in the application of aircraft rotor blades. On one hand, they can reduce the mass of the blades. On the other hand, they can reduce the centrifugal force generated by the rotation of the blades, realize the optimized design of the disk and shaft, and contribute to the weight reduction of the aero-engine structure. So far, the development of TiAl alloys has gone through three generations. The first-generation TiAl alloys have not been applied. The second-generation TiAl alloys (4822 and 45XD alloys) developed by the United States have been used in engineering. Various low-pressure turbine blades of aero-engine have been prepared by casting process, and the long-term service temperature of the blades is 650 ℃. At present, a variety of the third-generation TiAl alloys, including TNM, TNB, G8, etc., have been developed. These alloys have good comprehensive mechanical properties at 750 ℃. The third-generation TiAl alloys have not been used in engineering in the field of aero-engine. This paper reviews the development process of TiAl alloys for aero-engine, briefly summarizes the types of solid solution strengthening and precipitation strengthening elements in forged TiAl alloys, reviews the research process and current situation of the microstructure and properties, remelting process, hot working process and application of wrought TiAl alloys, analyzes the characteristics of three-phase and two-phase wrought TiAl alloys and elaborates the evolution of the microstructure and properties of two third-generation wrought TiAl alloys after long-term high-temperature exposure, providing a reference for the material selection of the third-generation wrought TiAl alloys by aero-engine designers.

Aviation cockpit transparency is the key structural-functional component of aircrafts, and its manufacturing technology represents a cutting-edge interdisciplinary field. Regarding the current research status in this field, this paper systematically reviews the development history and current technical state of advanced aviation transparent materials and transparency technology. The paper provides a detailed summary of research achievements in aviation transparent materials, molding technologies for single-layer and multilayer composite transparencies, functional film systems for transparency and electrochromic technology. Finally, this paper provides an outlook on the development trends of advanced aviation transparent materials and transparency.

This paper reviews the research work carried out by the research group on wrought superalloys and their preparation processes over the past more than ten years. On one hand, regarding wrought superalloys for aerospace applications, including high-strength hard-to-deform superalloys serving above 750 ℃, a new generation of low-expansion superalloys with both structural and functional properties, and wrought superalloys for high-strength fasteners at elevated temperatures, the microstructural characteristics and typical properties of these new materials are elaborated. On the other hand, in terms of wrought superalloys for nuclear reactors, the research progress and microstructural and performance characteristics of corrosion-resistant and irradiation-resistant high-temperature nuclear structural materials are introduced. Meanwhile, the research progress of advanced technologies such as the hot extrusion cogging process for fine-grained and homogeneous wrought superalloy bars and the hot extrusion forming process for hollow thin-walled long shaft forgings is presented. Finally, the research and development of wrought superalloys, process technology advancement, and industrial prospects in China are prospected: (1) establish an independent forward research and development system; (2) break through the full-process stable preparation technology; (3) expand cross-domain applications; (4) promote the large-scale recycling of returned materials.

Powder metallurgy superalloys have become the preferred material for turbine disks of advanced aero-engines due to their advantages such as segregation-free microstructure, uniform microstructure distribution, and excellent comprehensive properties. However, their highly alloyed composition and complex manufacturing processes make the traditional trial-and-error research mode confronted with multiple challenges, including long development cycles, high research costs, and unclear research orientation. Digital technologies have emerged as a critical approach to breaking through the above bottlenecks. This paper summarizes the applications of the full-scale digital technology system covering electron, atomic, mesoscopic, and macroscopic scales in the research of powder metallurgy superalloys, and prospects its future development trends. At the electronic scale, first-principles calculations and related methods are mainly adopted to screen alloying elements, clarify the mechanism of phase stability, and calculate the interfacial energy of γ/γ′ two-phase structures. At the atomic scale, molecular dynamics simulations are used to reveal the influence of inclusions on crack initiation and propagation, as well as the interaction mechanisms of dislocations, twins, grain boundaries, and other microstructural features during deformation. Mesoscopic scale methods, such as crystal plasticity, phase field, and cellular automaton, are applied to simulate the evolution of particle sintering, two-phase microstructure and grain structure, and their effects on mechanical properties. Macroscopic scale methods focus on simulating the evolution of macroscopic stress field, temperature field and average mesoscopic microstructure field in manufacturing procedures including powder preparation, hot isostatic pressing and heat treatment. Artificial intelligence and digital twin technology are revolutionizing the research and development of powder metallurgy superalloys. Based on massive experimental data, artificial intelligence adopts various algorithms represented by machine learning to provide definite guidance and schemes for composition optimization and process improvement. Digital twin establishes virtual mapping of physical components, aiming to realize accurate full-process simulation, real-time condition diagnosis, and life prediction throughout manufacturing and service stages. Finally, this study points out that future digital technologies need to develop toward the integrated prediction and optimization of cross-scale and cross-process preparation-service performance, so as to support the upgrading and innovation of aero-engine turbine disks with short development cycles, low costs, high reliability, and long service life.

MXene, as a typical two-dimensional transition metal carbide/nitride, exhibits broad application prospects in intelligent electromagnetic fields owing to its exceptional electrical conductivity, tunable interlayer spacing and rich surface functionalization. This review systematically summarizes recent advances in the synthesis, performance modulation strategies and research progress of MXene-based composites within the domain of electromagnetic functional materials. Firstly, it introduces the fundamental structural and electronic characteristics of two-dimensional MXene and critically examine prevailing synthesis routes alongside the resulting microstructural features of MXene-based composites. Secondly, it deeply explores the performance control strategies for these composites, elucidating the underlying mechanisms of multidimensional interfacial optimization—including tailored structural design, targeted surface functionalization and synergistic hybridization. Finally, in response to the key challenges currently faced by MXene-based composite, such as inadequate environmental stability, underdeveloped scalable manufacturing protocols and difficulties in achieving balanced multifunctional integration—it proposes promising future research directions to facilitate their translation into high-end applications, particularly in aerospace and related advanced technological fields.

The iterative upgrading of advanced aero-engine technology has put forward higher requirements for the performance of thermal barrier coatings (TBCs). The traditional yttria-stabilized zirconia (YSZ) TBCs system can no longer meet the high-temperature and complex environmental service requirements of turbine blades. Rare earth zirconate materials have become the most promising candidate system for the next-generation TBCs of turbine blades due to their outstanding advantages such as excellent high-temperature phase stability, low thermal conductivity and good corrosion resistance. This paper systematically summarizes the research progress of rare earth zirconate TBCs prepared by electron beam physical vapor deposition (EB-PVD), comprehensively reviews their preparation characteristics, core properties and failure mechanism. It focuses on elaborating the key performance characteristics of rare earth zirconate materials, including phase structure, thermal conductivity, thermal expansion coefficient and resistance to calcium-magnesium-aluminosilicate (CMAS) corrosion, and deeply analyzes the characteristics of their multi-inducer coupled failure behavior. Finally, the technical development paths for segregation control of rare earth zirconate coatings, and the design of ultra-low thermal conductivity and high thermal expansion coatings are clarified, and the future research directions of their specific CMAS corrosion mechanism and multi-factor related failure behavior model are prospected.

Refractory high-entropy alloys（RHEAs） are widely used in the aerospace field due to their excellent high-temperature performance. This study employs multi-wire arc additive manufacturing（M-WAAM） technology to fabricate Ta_1.5Mo_1.5Nb_0.5Zr₂Ti refractory high-entropy alloy. Using equipment such as optical microscopy（OM） and high-speed cameras, the influence rules of base current, peak current, and peak time ratio on forming quality are investigated. The optimal process parameters for preparing the Ta_1.5Mo_1.5Nb_0.5Zr₂Ti alloy are determined（base current 100 A, peak current 300 A, and peak time ratio 35%）. Metallographic characterization demonstrates that the fabricated components exhibit excellent forming quality, with unmelted area ratio below 10% and porosity less than 0.5%. To address the melting point differences among various wires, hot-wire technology is employed to facilitate the melting of high-melting-point Ta/Mo wires. For the first time, we propose a“single droplet pre-alloyed transfer”mechanism, elucidating the thermodynamic process of discontinuous liquid bridge transition and subsequent formation of a unified molten droplet from four simultaneously fed wires. Based on the thermodynamic mechanism of synchronous four-wire discontinuous liquid bridge transition forming a unified molten droplet, a“single droplet pre-alloyed transfer”mode is established. Parts deposited under this droplet transfer mode demonstrate good macroscopic morphology and fewer internal defects. Through force analysis of molten droplets, we establish a mechanical model incorporating key factors including gravity, electromagnetic force, and plasma flow force, demonstrating that synchronous non-continuous liquid bridge transition of four wires constitutes a sufficient condition for the formation of a unified molten droplet. Additionally, the developed bead width prediction model provides quantitative guidance for process optimization. This work establishes an important theoretical foundation for M-WAAM of RHEAs.

The K418B superalloy is fabricated utilizing laser powder bed fusion (LPBF) technology, and an analysis is conducted to examine the impact of process parameters on microdefect, density, microstructure, and hardness by OM, SEM and hardness tester. This is achieved by varying the laser power (ranging from 140 W to 220 W) and scanning speed(between 600 mm/s and 1400 mm/s). The findings reveal that both laser power and scanning speed significantly influence the relative density and defect distribution of the samples. Specifically, low energy density leads to the formation of irregular pores, whereas high energy density is associated with the emergence of spherical pores and solidification cracks. Excessive or insufficient volume energy density (VED) results in decreased density and impaired performance. The optimal processing conditions are identified as a laser power of 180 W and a scanning speed of 1400 mm/s, under which the sample density exceeds 99.95%, with minimal surface defects and only a small quantity of solidification cracks. Microstructure reveals distinct melt pool boundaries and cellular structure, accompanied by a Vickers hardness of 366.8 HV_0.2. Notably, the grains at the melt pool boundaries are coarse, with cellular columnar crystals spanning multiple melt pools, indicating rapid solidification. The hardness initially increases and then decreases with VED, aligning with changes in pore content and density. The study attributes cracks primarily to thermal stress and provides a foundational basis for optimizing LPBF processing parameters of K418B alloy, holding potential engineering applications for enhancing the manufacturing quality of critical aero engine components.

As an emerging moulding technology, 3D printing has steadily matured and is poised to supplant the traditional hot-press injection moulding technology, emerging as a pivotal approach for manufacturing ceramic cores in aerospace turbine blades. Nevertheless, 3D-printed ceramic cores produced through 3D printing display significant anisotropy in mechanical properties, including sintering shrinkage rate and strength, owing to their layered structure and directionally arranged porosity. This anisotropic characteristic severely impedes their manufacturing potential and application scope, posing a critical challenge that demands urgent resolution. This paper offers a systematic summary of the manifestations of anisotropy in 3D-printed ceramic cores, clarifies the underlying formation mechanisms, formulates evaluation criteria, and puts forward effective control strategies. Additionally, it delineates future research directions, encompassing material system innovation, process optimization, comprehensive property regulation, multi-technology integration, and intelligent manufacturing methods. These endeavors lay a solid theoretical groundwork for promoting the high-performance realization and large-scale application of 3D-printed ceramic cores.

Additive manufacturing is a near-net shaping technology that builds three-dimensional solid parts by depositing material layer by layer. It offers unique advantages in producing metal parts with complex structures. As a result, it has been widely used in key fields such as aerospace, biomedical and high-end mold manufacturing. However, the unique forming process of additive manufacturing introduces defect characteristics that differ from those in traditional manufacturing methods. These issues severely affect the service reliability of the formed parts and have become a critical challenge for the technology. This paper systematically summarizes the research findings of AECC Additive Manufacturing Technology Innovation Center on defects in additively manufactured metal materials. It focuses on the morphological features, formation mechanisms and effects on mechanical properties of typical defects such as holes, lack of fusion, inclusions and cracks. The paper also analyzes the role of hot isostatic pressing in closing defects and improving mechanical properties. To address current research gaps, it suggests further studies in several areas. These include revealing the relationship between defect formation mechanisms and process parameters, developing metal materials specifically for additive manufacturing, establishing defect acceptance standards based on part service requirements, and advancing intelligent online monitoring and closed-loop control technologies. These efforts aim to promote further progress of additive manufacturing.

This paper reviews the epoch-making significance of advanced materials in the history of human civilization, emphasizes that materials fall within the scope of applied science and the purpose of materials research lies in application. The “two whole processes” endow materials with ultimate intrinsic properties and ultimate service performance, thus forming the discipline of “Materials Science and Engineering”. This is the only way to build a leading country in materials. Five commanding heights for such a country are proposed, namely commanding heights in theory, technology, performance, industry, and system.

Radar and infrared stealth materials play a crucial role in enhancing the stealth performance of equipment. In recent years, vanadium-based oxides have shown broad application prospects in the field of radar and infrared stealth due to their unique thermochromic phase transition properties and excellent infrared radiation modulation capabilities. This paper summarizes the research progress of vanadium-based oxide radar and infrared stealth materials at home and abroad. From three dimensions of multi-component design, structural regulation and element doping modification, it systematically elaborates on the performance optimization methods and mechanisms of vanadium dioxide, vanadium trioxide and vanadium pentoxide-based stealth materials. Furthermore, this paper proposes five key directions for future research on vanadium-based oxide stealth materials: (1) the design of new heterostructure, which aims to overcome the inherent defects of vanadium-based oxides through structural regulation to enhance stealth performance; (2) artificial intelligence-assisted material design, which will utilize machine learning to model the composition-structure-performance relationships and accurately predict performance parameters, thereby shortening the material development cycle; (3) the synergistic optimization of multiple loss mechanisms, intended to couple conductive loss, dielectric loss and magnetic loss for synergistic enhancement, maximizing the improvement of stealth performance; (4) the characterization of complex interfaces, which focuses on strengthening interface characterization to reveal the wave-absorbing mechanism of composite systems in view of the complex interfaces caused by rich valence states; (5) broadband adaptive stealth, which involves developing stealth materials with both broadband and adaptive response capabilities based on thermally induced phase transition characteristics.

NiCrAlY is a commonly used metallic bond coat material for thermal barrier coating in gas turbines. This study investigates the effect of two NiCrAlY powders with different aluminum contents for gas turbine fabrication on the thermal cycling behavior of HVOF-NiCrAlY+APS-nanostructured YSZ (nYSZ) thermal barrier coatings (TBCs) within the temperature range from room temperature to 1150 ℃. The results show that the growth rate of the Al₂O₃ thermally grown oxide (TGO) on the surface of HVOF-Ni25Cr5Al0.5Y is lower than that of HVOF-Ni22Cr10Al1Y. Similar to the microstructured YSZ (mYSZ)/mYSZ interface, the nYSZ/mYSZ interface can also act as a crack initiation site, leading to the formation of a local crack network in the nYSZ layer. The failure mechanism of two HVOF-NiCrAlY+APS-nYSZ TBCs is consistent with that of the traditional APS/HVOF-MCrAlY (M=Ni and Co)+APS-mYSZ system, which is mainly attributed to the propagation and coalescence of cracks in the nYSZ layer adjacent to the HVOF-NiCrAlY/APS-nYSZ interface. The thermal cycling lifetime of the Ni25Cr5Al0.5Y+APS-nYSZ coating is slightly longer than that of the Ni22Cr10Al1Y+APS-nYSZ coating. Meanwhile, it can effectively improve the thermal cycling life of HVOF-MCrAlY+APS-YSZ TBCs to increase the bonding strength of the YSZ/YSZ interface in the APS-YSZ layer and avoid cracking at the YSZ/YSZ interface and the outer surface of the APS-YSZ.

The rapid development of stealth technology has put forward the demand for lightweight, broadband and high temperature microwave absorption materials. Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) ceramics are selected as lightweight and high temperature microwave absorption materials, and periodic structure is designed on its surface to expand its absorption bandwidth. LATP ceramics are sintered by the high temperature solid state method. The HFSS software is used to design the periodic structure on its surface. The effects of the geometric parameters and periodic parameters of patches with different shapes on their microwave absorption properties are studied, and the genetic algorithm is adopted to optimize the periodic structure. Results show that strong electromagnetic resonance occurs near the patches of the periodic structure, effectively improving the absorption bandwidth of LATP ceramics. Compared with LATP ceramics without periodic structure, the secondary optimized rectangle ring patch can expand the absorption bandwidth with RL <−10 dB from 2.69 GHz to the entire X band. Moreover, it can increase the absorption bandwidth with RL <−15 dB from 0 GHz to 3.82 GHz. At the same time, it can also reduce the minimum reflectivity and the thickness of the ceramic.

The internal displacement change around shrinkage pores, stress and strain distribution, and microstructural evolution in the defect healing zone of ZTC4 titanium alloy during hot isostatic pressing (HIP) are investigated by numerical simulation combined with experimental methods. The results demonstrate that under the high-temperature and high-pressure conditions of HIP, high stress-strain zones form around the shrinkage pores. The stress magnitude shows an inverse relationship with the distance from pore surfaces, exhibiting higher stress levels in proximity to the pore boundaries. As the shrinkage pore size decreases, the strain concentration intensifies. After HIP, a radial pore-healing zone microstructure develops at the original shrinkage pore sites. Within this healed region, heterogeneous plastic deformation occurs among distinct α/β colonies. Colonies with more readily activated dislocation slip systems experience greater deformation magnitudes, ultimately leading to the formation of equiaxed grain structures.

As high bypass ratio turbofan aero-engines develop towards longer service life and higher reliability, the mechanical property testing and characterization of materials have become the key to ensuring their long-term reliable operation. This paper systematically reviews the progress in the testing technologies, damage characterization and service life prediction of aeroengine materials for long-life design, mainly focusing on three typical scenarios: very-high cycle fatigue of rotor blade materials, long-term high-temperature creep of turbine hot-end components and fatigue crack characterization of real process defect-limited-life materials. It introduces the application of technologies such as very-high-frequency vibration fatigue based on electromagnetic vibration tables, creep measurement based on DIC methods, creep life prediction based on segmented models/physical mechanisms and in-situ fatigue based on SEM/CT in this field. In the future, it is necessary to further study the physical mechanisms of very-high cycle fatigue crack initiation, long-life creep rate stress dependence and microstructure evolution and real process defect damage evolution of aeroengine materials. Meanwhile, it is necessary to further promote intelligent life prediction models based on transfer learning, reinforcement learning, attention mechanisms and so on to achieve an integrated evaluation of the microstructure-performance-life of aero-engine components, in order to meet the continuous challenges brought by future aero-engines.

This study systematically investigates the effects of trace Gd additions of 0.5% (mass fraction, the same hereinafter) and 1.0% on the microstructure and tensile property of ZK60 magnesium alloy. The as-cast and solution-treated microstructures of ZK60, ZVK600, and ZVK610 alloys are characterized by optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, differential scanning calorimetry, and X-ray diffraction. The tensile properties of the alloy specimens are measured and analyzed via room-temperature tensile tests. The results show that the as-cast ZK60 alloy has grain size of 95 μm, with coarse blocky MgZn phases and a small number of Zn₂Zr₃ particles present at grain boundaries. Trace Gd addition increases the fraction of secondary phases and transforms the MgZn phase into the Mg₃GdZn₆ phase, but does not refine the grain size. The room-temperature tensile properties of the three as-cast alloys are relatively close. The as-cast ZVK610 alloy exhibits lower yield strength and ductility, which is associated with its relatively large grain size and increased grain-boundary secondary phases. After T41 step solution treatment, the grain of ZK60 alloy become oarse, the secondary phases are nearly eliminated, and the ductility is significantly improved. However, the yield strength decreases slightly due to grain coarsening. In contrast, a small amount of grain-boundary secondary phases remains in ZVK600 and ZVK610 alloys. T42 and T43 processes, designed with prolonged high-temperature solution time or elevated solution temperature, further reduce the secondary phase fraction in the matrix but lead to additional grain coarsening, resulting in further reduced yield strength and no obvious improvement in ductility. Therefore, T41 solution heat treatment process is recommended.

Adaptive thermochromic materials can meet the requirements of military dynamic camouflage application in the visible light band. However, a single thermochromic material is not suitable for the development of the battlefield as the requirements of the battlefield multi-band camouflage increase, especially the development of radar-band camouflage. Therefore, thermochromic/radar compatible technology is the issue that needs to be addressed. Adaptive thermochromic microcapsule materials are prepared by in-situ polymerization. The composition of microcapsule is analyzed using SEM, XRD and FTIR. The absorption properties of microcapsule, radar absorbing and thermochromic-radar composite materials are tested using coaxial method. The microcapsule materials are composed of thermochromic complex (fluorescent alkane dyes, bisphenol AF, dodecanol and conjugated color change substances) and urea formaldehyde resin. The corresponding thermochromic coating material includes thermochromic microcapsules, waterborne polyurethane and additives, which are compatible with each other. The microwave absorption test shows that the imaginary part of permittivity and permeability in thermochromic coatings are both zero, which possesses non-electrical and magnetic lossy properties, and does not significantly affect the wave-absorbing performance of the radar-absorbing coatings. The newly developed thermochromic coating material is a transparent to microwave due to the low electromagnetic loss capability. Finally, the thermochromic coating achieves excellent compatibility with radar stealth coatings.

This study systematically investigates the effects of long-line and short-line scanning strategies on the microstructure and mechanical properties of GH5188 superalloy fabricated by laser powder bed fusion (LPBF). Metallography and SEM results reveal that both strategies produce mixed microstructures composed of columnar and equiaxed grains. Due to the shallower melt pool and insufficient remelting, the short-line strategy retains finer grains at the melt-pool center, leading to further grain refinement (17.17 μm). In contrast, the long-line strategy provides a more stable heat-flow direction, resulting in stronger〈001〉texture development along the build direction and a slightly larger average grain size (20.86 μm). Mechanical testing shows that the two strategies lead to similar tensile strength and ductility at room temperature. At 980 ℃, the tensile strengths are comparable, while the elongation of the long-line specimens is 28.6% higher than that of the short-line specimens. Under the 927 ℃/90 MPa stress rupture condition, the long-line specimens exhibit a significantly longer rupture life (50.2 h±1.8 h) and higher ductility (10.1%±0.5%) than the short-line specimens (45.3 h±2.1 h; 7.6%±0.4%). Cross-sectional analysis shows that the short-line specimens contain more densely distributed cracks, along with pronounced carbide precipitation and coarsening at grain boundaries, indicating higher grain-boundary damage sensitivity. Fractographic analysis further confirms that cracks preferentially propagate along grain boundaries. These findings clarify the microstructural origins of high-temperature performance differences and provide guidance for optimizing LPBF scanning strategies for GH5188 alloy.

A numerical simulation study is conducted on SiC_f/SiC ceramic matrix composite turbine guide vanes to investigate the effects of variations in temperature ratio and flow ratio on the overall temperature and cooling performance of the vanes. A total of 16 operating conditions with variable temperature ratios and flow ratios are selected for simulation calculations. The results show that with the increase of both flow ratio and temperature ratio, the maximum temperature, minimum temperature and average temperature of the vanes all decrease, and high temperature occurs at the leading edge of the lower platform. The cooling efficiency of the vane suction surface increases gradually from the leading edge to the trailing edge, while that of the vane pressure surface first decreases and then increases from the leading edge to the trailing edge. For the local cooling efficiency, when the flow ratios are 5.28%, 7.54%, and 8.44%, respectively, the average cooling efficiency first decreases and then increases with the rise of temperature ratio. When the flow ratio is 3.69%, the average cooling efficiency decreases gradually as the temperature ratio increases. Meanwhile, the average cooling efficiency of the mid-section increases with the rise of flow ratio.

Carbon fiber reinforced polymer (CFRP) has significant application value in the aerospace field due to its lightweight and high-strength characteristics. However, during the hole-making process, the material’s anisotropic nature makes it susceptible to defects such as delamination and burrs, which can adversely affect the service performance and assembly quality of components. Therefore, it is necessary to conduct high-precision and high-efficiency detection on it. Based on the analysis of the defect mechanisms associated with hole-making in CFRP, this paper thoroughly examines the applicability of non-destructive testing technologies for CFRP hole-making defect. It analyzes the characteristics of traditional machine vision detection methods with those based on deep learning techniques. Furthermore, it emphasizes that intelligent detection technology utilizing multimodal data fusion provides significant advantages in enhancing both detection accuracy and efficiency. In addition, in response to the challenges currently faced by CFRP hole-making defect detection technologies, it proposes several development paths. These include the creation of an anisotropic adaptive detection algorithm, the establishment of a standardized defect classification system, and the implementation of online monitoring for the hole-making process. The aim is to provide innovative theoretical support and technical direction for intelligent and high-precision detection in the field of aerospace composite material manufacturing.

Soft magnetic alloys exhibit significant potential for applications in electromagnetic wave absorption in the gigahertz frequency band, owing to their advantages such as high saturation magnetization, excellent permeability, diverse microwave attenuation mechanisms, and flexibly tunable electromagnetic parameters. This paper provides a review of the research progress on soft magnetic alloys and their composites in the field of microwave absorption over the past five years. The methods for modulating the performance of soft magnetic alloy-based microwave absorbers are summarized, primarily including composition optimization, elemental doping and post-treatment processing, and the effects of these methods on electromagnetic parameters and microwave absorption performance are analyzed. Subsequently, the synergistic effects of incorporating hard magnetic materials, dielectric materials and insulating materials with soft magnetic alloys on enhancing microwave absorption performance are mainly discussed. Then, the auxiliary role of machine learning in the development of soft magnetic microwave absorbing materials is introduced. In summary, the development of soft magnetic alloys and their composites exhibits a clear trend toward diversification in material systems, preparation methods and morphological design. Looking forward, the deep integration of material experimentation, performance simulation and machine learning is expected to significantly accelerate the efficient development of microwave-absorbing materials in this field.