Thermoplastic composites（TPCs）have exhibited immense potential in aerospace applications, attributed to their exceptional toughness, weldability, recyclability, and efficient processing cycles. However, the manufacturing of complex structures is hindered by the high melting points and viscosities of their constituent resins. Resistance welding, leveraging Joule heating to induce interfacial melting and bonding, emerges as a viable alternative to mechanical fastening and adhesive bonding. This review delves into the fundamental principles underlying resistance welding, strategies for optimizing key process parameters, recent advancements in heating elements, and large-scale welding techniques, such as sequential and continuous resistance welding. The findings indicate that optimizing process parameters and improving heating elements can significantly enhance joint strength. To achieve engineering application of resistance welding technology, further research should be focused on process stability, reliability of welded joints, large-scale welding, and other issues.

As a critical strategic material for aero-engines and industrial gas turbines, the composition/process design, optimization and process control of superalloys remain at the core of industry concerns. The present work focuses on addressing practical challenges in the development and production of superalloys and their components. It identifies key influencing factors in typical processes within the manufacturing workflow and employs a combination of advanced characterization techniques such as synchrotron radiation and high-throughput experimental methods. This integrated approach enables the design and optimization of critical process parameters for superalloy manufacturing, thereby providing foundational support for enhancing process technology, product performance, research and development efficiency, and reducing costs. Taking representative manufacturing processes involving liquid-solid and solid-solid phase transformations as examples, we explore precision tailoring strategies and validation methods for key stages including master alloy melting/remelting, synergistic particle size/morphology control in gas atomization, shrinkage porosity control during casting solidification, powder storage/desorption treatments, powder consolidation through hot isostatic pressing（HIP） and heat treatment procedures. In addition, optimal usage conditions are investigated for auxiliary materials or consumables integral to superalloy production, particularly ceramics, isothermal forging dies and brazing repair materials. Notably, the research on process tailoring reveals significant phenomena: （1）the impact of oxygen existence forms in cast and powder metallurgy alloys; （2）the influence of the initial microstructural state of alloys on the phase transformation temperature during HIP consolidation and heat treatment; （3）the formation and control of abnormal phases and defects in cast, powder metallurgy and additive manufacturing alloys, along with repair materials for brazing and ceramic refractories. The aforementioned findings establish a theoretical foundation for optimizing and tailoring superalloy process parameters and achieving precise manufacturing control, while also providing feasible technical pathways for industrial implementation.

The machine learning technology has broad prospects in the field of aerospace materials and plays an important role in material selection, design, and optimization. Firstly, a brief discussion was made on the advantages and potential of machine learning technology in the aerospace field, outlining the technological developments, algorithm categories, features, and limitations. The conventional or potential applications of machine learning in scientific exploration, especially in complex material data formats, are introduced. Secondly, the research status of machine learning in aviation materials is mainly focused on, discussing the recent progress in utilizing machine learning to assist in the research of high-temperature alloy materials, high-strength structural materials, thermal protection coating materials, as well as functional and smart materials. The strategies and methods of machine learning-driven aviation material research are elucidated. Finally, the challenges encountered in machine learning-assisted aerospace material research and development are examined. Facilitating the transformation of aerospace material research towards the fourth paradigm of data-driven materials science necessitates efforts in promoting the open sharing of data resources, integrating domain knowledge and physical laws more deeply into machine learning models, and ensuring feature consistency across different data types.

Poly（aryl ether ketone）（PAEK） thermoplastic composites exhibit exceptional impact resistance and possess significant application potential in the aerospace industry. To address mechanical performance limitations of PAEK composites fabricated through automated in-situ placement, this study systematically investigates the impacts of post-processing parameters-including temperature, pressure and time-on pore elimination and mechanical properties. Utilizing the automated fiber placement, PAEK prepregs are processed into laminates. A viscosity-pressure-time coupling model is formulated through differential scanning calorimetry（DSC）, rheological assessments and mechanical characterizations. The results demonstrate the model predicts reasonably pore elimination across varying process parameters and the critical post-processing temperature is identified as 340 ℃. The pore elimination is facilitated rapidly due to low and stable resin viscosity at 340-360 ℃. The post-processing pressure significantly influences pore removal efficiency, with a critical pressure of 0.7 MPa at 360 ℃ and requiring 60 min for complete pore elimination. Higher pressures lead to only marginal performance enhancements. The time dependency of material performance depends on pressure: at 0.7 MPa and 360 ℃, full pore elimination is achieved within 60 min, whereas at 1.6 MPa, the required time is reduced to 20 min. At 0.7 MPa, 360 ℃ and 60 min, the tensile strength, flexural strength and interlaminar shear strength are 2844, 1653 MPa and 103 MPa, respectively.

High-performance thermoplastic resin-based composites have shown broad application prospects in the aviation manufacturing technology due to their excellent mechanical properties, environmental resistance, chemical resistance, recyclability, and rapid molding. In recent years, with the accelerated commercialization of high-performance thermoplastic resins such as polyphenylene sulfide（PPS）, polyetherimide（PEI）, and polyaryletherketone（PAEK）, the related prepregs and molding technologies have been continuously optimized, promoting the industrial application of such materials. This paper systematically reviews the current development status of high-performance thermoplastic resin-based composites, focusing on their material systems and commercialization progress, prepreg preparation, advanced manufacturing technology and application. It proposes key development directions for high-performance thermoplastic resin matrix composites, in order to provide reference for personnel in engineering and technical fields such as aerospace, and promote the innovative development and application of high-performance thermoplastic resin matrix composites.

This article provides an overview of the latest research status and application prospects of titanium/titanium alloy composite materials, highlighting their advantages in high specific strength, lightweight properties, thermal stability, and wear resistance, which position them as crucial materials in high-tech sectors such as aerospace, military equipment, and medicine. It summarizes research outcomes demonstrating the steady enhancement of mechanical properties, wear resistance, and thermal stability of titanium matrix composites through the addition of reinforcing phases. The review also reveals advancements in various processing technologies that have improved the grain structure and performance of these composites, while pointing out that challenges persist regarding the stability of these materials under high temperature and pressure conditions, as well as the bonding strength at interfaces. These issues necessitate the optimization of reinforcement distribution, bonding methods, and the exploration of novel composite systems. Furthermore, the combination of surface nanotechnology with digital simulation offers new avenues for optimizing the properties of titanium-based composites. Interface reinforcement and thermal stability research are identified as pivotal for future developments. Ultimately, the essay underscores that the enhancement of titanium-based composite properties and innovations in processing technologies are central to realizing their extensive application in extreme environments. This dual focus also constitutes the direction for pushing the boundaries of composite material performance even further.

Carbon fiber reinforced thermoplastic composite（CFRTP） is increasingly utilized in aerospace and automotive manufacturing sectors owing to its exceptional specific strength, strong toughness, and weldability. Induction welding stands as a pivotal method for fabricating typical CFRTP components. However, the intricate interplay of magnetic, thermal, and stress coupling during the induction welding process, along with its evolution and distribution characteristics, remains unclear, significantly impeding the cost-effective, efficient, and high-quality production of CFRTP components. In this study, a magnetic-thermal-mechanical coupling simulation model is developed for the induction welding of CFRTP stringer skin structures. This model is employed to investigate the distribution and evolution patterns of the magnetic field, temperature field, and residual stress field. The results show that under the influence of an alternating electromagnetic field, the magnetic field strength peaked at 1.45 mT in the component’s edge region. Notably, the simulated magnetic, temperature, and stress field all exhibit significant edge effects, which are intimately tied to the skin effect induced by high-frequency eddy currents. During welding, asymmetric and nearly elliptical high-temperature zones emerge on both sides of the skin’s bottom, with temperatures in proximity to the stringer area notably higher than those farther away. When the current frequency increases from 150 kHz to 250 kHz, the maximum stress of the induction joint increases from 637 MPa to 778 MPa, and the asymmetric stress concentration area at the welding interface expands accordingly. The measured temperature field and stress results are in high agreement with the simulation outcomes, effectively validating the model’s accuracy and applicability. This study offers theoretical backing for process optimization and quality control in the induction welding of intricate CFRTP components.

With advancements in material technology, a surge in research and development has been witnessed for various high-performance materials, including metamaterials, each possessing unique functionalities. However, meeting the demands of high performance has rendered the application of a single material insufficient for achieving the required interface mechanical and functional integration properties. Functionally gradient composite materials have emerged as a pivotal breakthrough to address this issue. This paper introduces the application background, as well as the research and application status of functionally gradient composite materials in foreign countries. Furthermore, based on the prevalent issues in the domestic engineering field concerning functionally gradient composite materials, the challenges faced in their utilization are highlighted. When compared to international advanced levels, the development of functionally gradient composite materials in China encounters three major hurdles. Firstly, the preparation process remains relatively underdeveloped, impeding large-scale engineering applications. Secondly, due to the scarcity of performance evaluation methods, there is an urgent necessity to establish a coupled functional evaluation system. Thirdly, there is a scarcity of proprietary intellectual property rights pertaining to material design and simulation methods, coupled with the absence of a comprehensive database. Consequently, material design still largely relies on the experience of designers. Lastly, suggestions for the future application and development of functionally gradient composite materials are proposed.

High-temperature high-entropy alloys（HEAs）show potential to surpass traditional Ni-based alloys through multi-principal element synergy and microstructural regulation. This review systematically examines three systems: high-entropy superalloys（HESAs）, refractory HEAs（RHEAs） and refractory high-entropy superalloys（RSAs）. HESAs emulate the γ/γ′ dual-phase structure of Ni-based alloys, achieving comparable strength at 800-1000 ℃. RHEAs utilize refractory elements to form high-melting-point solid solutions with superior performance above 1200 ℃. RSAs innovate with BCC/B2 nanobasket structures, outperforming Ni-based alloys across 25-1200 ℃. Current challenges include poor room-temperature ductility, oxidation resistance and phase stability, demanding breakthroughs in multi-scale microstructure control, dynamic phase transformation mechanisms and high-throughput design. Future directions prioritize multi-objective composition optimization, advanced processing, cross-scale characterization, and service-condition evaluation systems to guide extreme-environment applications like aeroengine components and nuclear reactors, etc.

The resistance welding process of 7075 aluminum alloy（7075AA） and carbon fiber reinforced polyether ether ketone（CF/PEEK） is optimized through the activation of the aluminum alloy surface and its subsequent integration with a thermoplastic layer. A microgroove network is fabricated on the aluminum alloy surface using laser treatment, which notably augmented the mechanical coupling with the polyetherimide（PEI） thermoplastic layer. In contrast, the bonding effectiveness of sandblasted and untreated samples are inferior. Surface analysis conducted via Fourier transform infrared spectroscopy（FT-IR） and X-ray photoelectron spectroscopy（XPS） reveal the formation of Al—O—Si bonds and a silane coupling film transition layer, both of which fortified the interface. In the resistance welded joints, incomplete bonding between the sandblasted/laser-etched aluminum alloy and the PEI layer lead to debonding of the thermoplastic layer, which emerge as the predominant failure mode. The single lap shear strength（LSS） of the sandblasted joint is 10.47 MPa, whereas the LSS of the laser-etched joint attains 15.35 MPa. Following silane treatment, the bonding of the PEI thermoplastic layer is markedly enhanced, resulting in an LSS of 19.03 MPa for the laser-etched and silane-treated joint—a 23.97% increase compared to simple laser etching. At this juncture, the cross-section of the joint exhibites characteristics indicative of heating element fracture, with the failure mode transitioning to interlayer fracture.

To address the challenge of inconsistent forming quality observed in carbon fiber-reinforced polyaryl ether ketone（CF/PAEK）composites during in-situ automated fiber placement（AFP）, this study introduces a vacuum-assisted in-situ annealing（VIA）process implemented subsequent to layup. The study systematically examines the impact of VIA parameters—specifically annealing temperature and holding time—on various aspects of CF/PAEK unidirectional laminates, including temperature field uniformity, warpage deformation, porosity, crystallinity, and interlaminar properties. Experimental findings reveal that the VIA process facilitates a uniform temperature field, mitigates crystallinity gradients, and progressively diminishes warpage deformation with an increase in annealing temperature, ultimately achieving complete elimination of warpage. Notably, when the annealing temperature surpasses the resin melting point, internal pores formed during the CF/PAEK prepreg or AFP process undergo substantial reduction, resulting in a porosity level of merely 2%. Furthermore, the interlaminar performance exhibits a remarkable enhancement, with an interlaminar shear strength（ILSS）of 64.66 MPa—representing a 58.6% improvement compared to specimens that have not undergone VIA treatment.

IN718 superalloy is extensively utilized in the aerospace and nuclear industries due to its outstanding oxidation resistance, heat-corrosion resistance, good structural stability, fatigue performance and safety reliability. It is one of irreplaceable materials for the hot-end components of next-generation advanced aircraft engines. Recently, laser powder bed fusion（LPBF） technology has developed as an innovative rapid prototyping technique, transcending the limitations of traditional shaping methods and structural designs. This technology has realized one-step laser near-net shaping of complex thin-walled structures, demonstrating substantial application potential. However, during the laser additive manufacturing process, the thin-walled surfaces are exposed to high laser input energy, which can readily induce warping, deformation, and even cracking, significantly impacting the service performance of these structures. To address these challenges, this work provides an overview of the working principle and recent advancements in LPBF technologies. It systematically analyses the multi-scale microstructural evolution and precipitation phase behavior of IN718 superalloy thin wall fabricated by LPBF. Special emphasis is placed on the initiation, propagation mechanisms and mitigation strategies for metallurgical defects, including optimized thin-walled structural designs, laser forming process parameters and alloy composition. In addition, the strengthening mechanisms underlying the mechanical properties of IN718 superalloy thin wall at both room and high temperatures are analyzed and discussed. Finally, the work summarizes the existing challenges such as insufficient critical performance under harsh conditions and future development directions of superalloy thin wall fabricated by LPBF, including establishment of laser forming process databases specialized for superalloy thin wall, investigation of solidification defect formation and novel control strategies in superalloy thin wall fabricated by LPBF, and optimization of the chemical composition design for high-performance superalloy thin-walled components.

This study investigates the performance evolution of T800/polyaryletherketone（PAEK） thermoplastic composites subjected to hygrothermal aging conditions. By meticulously controlling the cooling rate, two distinct types of carbon fiber-reinforced PAEK composites with varying crystallinities are prepared: CF/PAEK-CL（low crystallinity） and CF/PAEK-CH（high crystallinity）. These composites are then systematically examined for their moisture absorption behavior, thermal properties, and mechanical performance in hygrothermal environments. Experimental results reveal that the water absorption of CF/PAEK composites increases progressively over time, with CF/PAEK-CL exhibiting a notably higher moisture uptake rate due to its lower crystallinity. Following hygrothermal aging, the glass transition temperature（T_g） of all samples decreases, with CF/PAEK-CL experiencing a specific reduction of approximately 5%. Thermal analysis further indicates that hygrothermal aging has a negligible impact on the crystallinity of the materials, and notably, the high-crystallinity composite demonstrates superior thermal stability in such environments. Flexural testing results demonstrate that hygrothermal aging has a limited influence on the flexural strength and modulus of CF/PAEK composites, underscoring their robust resistance to the detrimental effects of hygrothermal conditions on flexural mechanical properties. This resilience ensures their long-term stability and reliability in harsh environments. The findings of this study offer pivotal data and theoretical insights, paving the way for the application of CF/PAEK composites in demanding service conditions.

Titanium alloys are widely used in the fields of aviation, aerospace and marine due to their excellent strength, weldability and plasticity. This study focuses on a near-α titanium alloy Ti-6.5Al-2Zr-Mo-V（TA15）, fabricated by selective laser melting（SLM） technology. The impact of laser scanning speed on the macroscopic morphology and microstructure of the TA15 alloy is investigated using a range of analytical methods such as confocal laser scanning microscopy（CLSM）, optical microscopy（OM）, scanning electron microscopy（SEM）, X-ray diffraction（XRD） and energy dispersive spectroscopy（EDS）. The results show that variations in laser scanning speed significantly influence the forming quality of the alloy. Specifically, higher scanning speeds induce discontinuous fluctuations in the melt pool and irregular surface undulations, whereas lower speeds promote porosity formation at the cross-section. Initially, an increase in laser scanning speed enlarges the size of the martensite structure, followed by a decrease, accompanied by a gradual reduction in martensite hierarchy. Low or high laser scanning speeds cause local cracks on the alloy surface, where elemental depletion and enrichment are observed. These findings demonstrate a direct correlation between laser scanning speed and alloy forming quality. These results provide valuable insights for optimizing the process parameters and strategies of SLM for TA15 alloy, thereby facilitating its further promotion and application.

With the upgrading of information security, target stealth and electromagnetic protection, the urgent development of highly efficient wave-absorbing materials is imperative. This paper briefly describes the working principle of wave-absorbing materials, and comprehends the research progress of coated and structural wave-absorbing materials, and finally focuses on the development of fiber hybrid wave-absorbing composites: the fiber arrangement, component regulation and interface design can synergistically enhance the electromagnetic and mechanical properties. Through multi-fiber synergistic design and multi-scale structural optimization, fiber hybrid wave-absorbing composites can realize the coupling optimization of impedance matching and loss mechanism, and have both broadband absorption and mechanical loading characteristics, which promote the development of wave-absorbing materials in the direction of structural and functional integration. Finally, the technological breakthrough of expanding the wave-absorbing frequency band through multi-fiber blending system is summarized, and the future development of a new generation of dual-use wave-absorbing materials with broadband absorption, lightweight and high-strength characteristics around the deepening of the fiber blending mechanism, multi-scale structural design, improvement of the environmental adaptability, multi-functional integration, synergistic control of the fiber orientation and angle of incidence, and the development of high-temperature ceramic-based wave-absorbing materials are prospected.

Optimizing the directional solidification process of nickel-based superalloys is pivotal for enhancing the quality of hot-end castings in aero-engines. Traditional process optimization methods have heavily relied on empirical trial-and-error approaches, whereas numerical simulation technology is increasingly emerging as a pivotal tool. This paper presents a comprehensive review of the latest advancements in numerical simulation pertaining to the directional solidification process of nickel-based superalloys. It emphasizes modeling methodologies, simulation outcomes, and their practical applications in process optimization and defect control（such as stray grains and freckles） across various multi-physics fields, encompassing temperature fields, fluid flow and solute transport, stress-strain fields, and microstructural aspects（grains and dendrites）. A synthesis of current research reveals that numerical simulation studies still grapple with several shortcomings: a high degree of dependence on approximate boundary conditions in models; inadequate refinement and limited global optimization capabilities within process windows; incomplete numerical representations of certain crystalline defects and complex defect interactions; and substantial computational resource demands for high-fidelity microstructural simulations. To tackle these challenges, future research trends are anticipated to concentrate on deepening and integrating multi-physics and cross-scale coupling models, leveraging artificial intelligence-driven simulation and optimization, enhancing the precise characterization of solidification mechanisms in multi-component alloys, and strengthening experimental-simulation collaborative validation systems through the integration of in-situ characterization techniques with simulations. By advancing in these areas, numerical simulation technology is poised to play a pivotal role in achieving precise control over the morphology and properties of complex castings, while effectively mitigating defects.

The mechanical properties and thermodynamic stability of nickel-based single-crystal superalloys are largely dependent on the charateristics of the precipitated phase interface. In this work, density functional theory（DFT）is utilized to investigate the influence of alloying elements, specially Co, Cr, Mo, W, Re and Ta, on the mechanical properties of γ-Ni/γ′-Ni₃Al interface. Following a convergence analysis to the optimal computational model, our findings reveal that Re and W exhibit the most significant strengthening effects within both the γ and γ′ phases. Notably, Re stands out for its substantial enhancement of Young’s modulus（27 GPa and 11 GPa）and shear modulus（16 GPa and 6 GPa） in the γ and γ′ phases, respectively, while Ta demonstrates a unique proficiency in augmenting the bulk modulus of 21 GPa and 14 GPa in the γ and γ′ phases, respectively. Analysis of interfacial tensile properties indicates that the Re-doped system exhibit the highest ideal tensile strength（approximately 25 GPa）and deformation energy（approximately 1.84 J·m⁻²）. Furthermore, the strengthening impact of alloying elements on interface tensile properties diminishes in the order: Re＞W＞Cr＞Mo＞Ta＞Co＞undoped. Analyses of differential charge density and density of states reveal that the strengthening mechanisms of theses alloying elements are attributable to the augmentation in the chemical bonding strength between doped atoms and their nearest-neighbouring host atoms. Electron orbital characteristics indicate that these alloying elements contribute to retarding interfacial fracture by maintaining local structural stability. A series of results provide ideas for the development of novel nickel-based single-crystal superalloys.

The tribological properties and wear mechanisms of PTFE filled with graphene at mass fractions of 0.5%, 1%, 3%, 5%, and 7% are investigated, and these are compared with those of PTFE filled with the traditional modifier MoS₂ at mass fractions ranging from 5% to 25%（in increments of 5%）. Additionally, a synergistic modification of PTFE with a combination of "graphene+MoS₂" is conducted, focusing specifically on the tribological properties and wear mechanisms of composites containing MoS₂ at a mass fraction of 15% combined with graphene at mass fractions of 1%, 3%, and 5%. The findings reveal that the incorporation of graphene significantly enhances the tribological performance of PTFE and its composites. Notably, the optimal tribological properties are observed when graphene is present at a mass fraction of 5%, exhibiting an average friction coefficient of 0.0763 and a volumetric wear rate of 230.34×10⁻⁹ mm³·N⁻¹·m⁻¹. The predominant wear mode shifts from adhesive wear to fatigue wear under these conditions. When graphene is used in conjunction with MoS₂ for synergistic modification, it effectively addresses the issue of poor compatibility between MoS₂ and PTFE, mitigating the tendency of MoS₂ to be worn away and causing abrasive wear during friction.

In order to investigate the effect of low-angle grain boundary（LAGB） on the high-temperature creep behavior of a second-generation nickel-based single-crystal（SX） superalloy, the high-temperature creep fracture and interrupted experiments are carried out at 1100 ℃/137 MPa using plate-shaped samples with different grain boundary misorientations. The results show that after standard heat treatment, fine MC carbides are formed at the LAGB with the misorientation of 7° in alloy GB-7, while blocky M₆C carbides are formed at the LAGB with the misorientation of 12° in alloy GB-12. The high temperature creep life of the investigated alloys decreases with increasing the misorientation degree. The creep life of alloy GB-12 is only 40% of that of the single crystal alloy. Further investigation reveals that LAGB migration occurrs in both the GB-7 and GB-12 alloys during high-temperature creep, but the migration distance of the GB-12 alloy is lower than that of the GB-7 alloy. Blocky M₆C carbides in alloy GB-12 hinder the grain boundary migration, leading to strain concentrations at the LAGB region. Cracks tend to initiate at the low-angle grain boundary either inside GB-12 alloy or on its surface, leading to a significant reduction in its creep life. This study can provide guidance and data support for improving the tolerance of LAGBs in high-temperature creep.

Based on the hot-ended casing of K4169 superalloy as the research object, aiming at the defects such as liquid splashing, oscillation and entrained air in the linear filling process of traditional superalloy counter-gravity casting, particularly, considering the complex variable cross-section structure of the casing castings, the work explores the influence of pressurization speed on filling of such structure through hydraulic simulation experiments. The results reveal that for the variable cross-section structure, a lower pressurization speed leads to more stable liquid filling. Orthogonal experiments are conducted to ascertain the optimal filling process parameter of the casing model such as a pouring temperature of 1460 ℃, a shell temperature of 900 ℃ and an average pressurization speed of 4 kPa/s. Based on the casing model’s structure, linear and nonlinear filling pressure curves are designed, and both numerical simulations and experimental studies are performed to compare two filling methods. When comparing two filling processes with the same filling time, the nonlinear filling exhibits a 16.77% decrease in average gate speed compared to the linear filling, resulting in a more stable filling process and production of fewer overall defects in the thin wall areas of the casing. Casings filled using the linear method exhibit numerous crack defects across various regions, leading to a relatively high overall defect rate. In contrast, casings filled using the nonlinear method devoid of crack defects and contain only a few micro-pores. Non-destructive testing results also support the notion that casing castings filled by the nonlinear method have fewer defects, which validates that the nonlinear filling effectively reduces the type and quantity of defects in casing castings.

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.

Grain refinement can effectively enhance mechanical properties of materials at low and medium temperatures, however, it may weaken the stress rupture property above the equicohesive temperature. To study the effect of grain refinement on the stress rupture property of K447A alloy, the microstructure evolutions of alloys with three grain sizes and their corresponding stress rupture mechanisms under the conditions of 760 ℃/724 MPa, 815 ℃/600 MPa, 870 ℃/365 MPa and 980 ℃/210 MPa are investigated using scanning electron microscopy（SEM） and energy dispersive spectroscopy（EDS）. The results show that the equicohesive temperature of K447A alloy lies between 815 ℃ and 870 ℃. Grain refinement shows a temperature-dependent effect on the stress rupture life of K447A alloy. At 760 ℃/724 MPa, as the grain size decreases from 5.0 mm to 1.3 mm and then to 58 μm, the stress rupture life of K447A alloy increases from 83 h to 115 h and further to 194 h, respectively. At 815 ℃/600 MPa, the stress rupture life increases from 31 h to 84 h, as the grain size decreases, and then slightly drops to 76 h. At 870 ℃/365 MPa and 980 ℃/210 MPa, the stress rupture life shows a monotonic decreases with grain refinement. Therefore, grain refinement serves as an effective technology to improve the stress rupture property of K447A alloy below 870 ℃.The stress rupture process is dominated by intragranular deformation below 815 ℃, and grain refinement mainly extends the stress rupture life by shortening the slip band length and increasing the volume fraction of γ′ phase. Above 870 ℃, grain boundary sliding dominates the stress rupture process. The deterioration of the stress rupture property due to grain refinement can be attributed to the severe grain boundary slip at high temperatures, grain boundary oxidation and the formation of brittle AlN and a low-strength precipitation free zone（PFZ）.

TiAl alloys have attracted much attention due to its excellent specific strength, specific stiffness, and high-temperature performance, which has great potential for application in the aerospace industry. With the development of aerospace technology, the performance requirements for its equipment and service materials have further increased. Thermomechanical treatment plays a very important role in the field of manufacturing technology of aerospace equipment. The mature preparation processes for TiAl alloys are mainly ingot metallurgy and powder metallurgy. TiAl alloys are obtained by both processes require subsequent thermomechanical treatment. Combining the processes of deformation with heat treatment, the microstructure of TiAl alloys can be effectively controlled, thereby improving the room-temperature brittleness and fracture toughness of alloys. On the basis of fully understanding the thermoplastic deformation behavior of TiAl alloys, further research on different hot working methods and processes, process parameter design and control of TiAl alloys are of great significance for reducing the processing cost of TiAl alloy products as well as promoting their production and application. This article mainly reviews the development status of thermomechanical treatment of TiAl alloys.The research progress in the thermoplastic deformation behavior as well as microstructure control of hotworking （hot forging, hot rolling, hot extrusion） and subsequent heat treatment of TiAl alloys is summarized. On the basis, this article proposes the development directions in thermomechanical treatment of TiAl alloys. The first is the research on thermomechanical treatment process of TiAl composite materials. On the basis of high-throughput material design, exploring the hot working and post-treatment process routes suitable for TiAl composites, is expected to develop a new type of TiAl material with excellent high-temperature comprehensive performance. The second is the optimization design of hot working process for large-sized TiAl alloy components. Combining machine learning methods to optimize the hot working parameters of large-sized TiAl alloy components, as well as predict the microstructure evolution during hot working, and developing new mold materials to effectively control the processing temperature, are expected to significantly improve the controllability and stability in the forming process of large-sized TiAl components. The third is the development of low-cost thermomechanical treatment technology of TiAl alloys, such as no package hot working technology and single-step heat treatment process. The fourth is the thermomechanical treatment control of new microstructures for TiAl alloys. On the basis of introducing nanostructures to refine the microstructure of TiAl alloys, a new type of TiAl alloy microstructure design is expected to carry out by thermomechanical treatment to further enhance the performance of TiAl alloys. The fifth is the efficient screening of thermomechanical treatment process parameters for TiAl alloys. Integrating multidisciplinary knowledge, constructing a large database of components, hot working/heat treatment parameters, microstructure, and properties, can reduce the costs and cycles of researches.

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 creep properties of a corrosion resistant single crystal superalloy at 760 ℃/800 MPa, 980 ℃/250 MPa and 1120 ℃/130 MPa are investigated. The creep fracture microstructure, fracture characteristic and dislocation morphology under different conditions are analyzed using scanning electron microscopy（SEM）and transmission electron microscopy（TEM）. The results indicate that the alloy exhibits good creep performance at 760 ℃/800 MPa, 980 ℃/250 MPa and 1120 ℃/130 MPa, with its creep curves showing similar three-stage creep characteristics. As temperature increases and stress decreases, the creep lives of the initial and acceleration stages becomes shorter, while the creep life of the steady-state stage increases. Compared to 980 ℃/250 MPa and 1120 ℃/130 MPa, the creep rate during the initial stage is faster at 760 ℃/800 MPa. Under 760 ℃/800 MPa conditions, the γ′ phase retains its cuboidal morphology. The dislocation tangles forming in the matrix channels and stacking faults forming from some dislocation cutting γ′ phase have a reinforcing effect. The creep fracture morphology of the alloy involves cleavage-like and ductile dimple mixed fracture. At 980 ℃/250 MPa and 1120 ℃/130 MPa, the alloy exhibits obvious rafting behavior and topological inversion of γ′ phase and γ phase has finished. A high-density dislocation network forming at the γ/γ′ interfaces have a reinforcing effect. No stacking faults are observed to form. Dislocations cut into the γ′ phase during the later stage of creep.The creep fracture morphology is dominated by ductile dimple fracture. At 1120 ℃/130 MPa, a small amount of lamellar σ phases precipitate along specific directions in the alloy, indicating good microstructural stability.

The high-temperature mechanical properties of cast nickel-based superalloy K4222 enhance through alloying of Hf. This work investigates the effect of adding mass fraction of 0.72% and 1.5%Hf on the microstructure and high-temperature stress rupture properties of the alloy. The results reveal that the addition of Hf not only increases the MC carbide content in the alloy, but also facilitates the formation of eutectic （Ni₅Hf + γ） phases. After heat treatment, M₂₃C₆ carbides are dissolved at high temperature and MC carbides are degraded, resulting in an overall reduction in the carbide content of each alloy and the elimination of eutectic phases. However, a small amount of Ni₅Hf phase remains in the 1.5%Hf alloy. Meanwhile, the results show that Hf can greatly improve the stress rupture life of the alloy. Compared with 0%Hf alloy, the stress rupture life of the 0.72%Hf and 1.5%Hf alloys increases 101.4% and 211.2% under the condition of 899 ℃/172 MPa, respectively. The improvement of Hf content will reduce the rupture plasticity of K4222 alloy to a certain extent, but 0.72%Hf still maintains good level. Further analysis shows that the addition of Hf can change the morphology of carbides, increase the grain boundary strength, reduce the occurrence of carbide cracking and intergranular cracks, and thus improve the high-temperature creep strength of the alloy.

To meet the lightweigh requirements, the structure of castings is evolving towards thin-walled designs. Therefore, it is necessary to study the evolution characteristics of the microstructures and mechanical properties of thin-walled structures made of nickel-based superalloys. Firstly, a thin-walled casting with wall thicknesses of 1, 1.25 mm and 1.5 mm is designed. Gravity casting experiments are conducted under two different process conditions, and the microstructural analysis and mechanical property tests are carried out for two types of castings, respectively. The values of microstructural characteristics are determined, including secondary dendrite arm spacing（SDAS）, grain morphology and average grain size, as well as the size and volume percentage of the γ′ phase at different wall thicknesses of the castings under different cooling conditions. The corresponding hardness and tensile strength also are measured by experiments. The results show that SDAS increases by more than 29.9% as the wall thickness of the casting increases from 1 mm to 1.25 mm and 1.5 mm. The tensile strength of the casting fluctuates with the increase in wall thickness when the flask temperature is 900 ℃. However, the tensile strength of the casting increases as the wall thickness increases when the flask temperature is 25 ℃. The variation range of the castings cooling rates are determined through numerical simulation. The cooling rate range of castings with a sand mold temperature of 900 ℃ ranges from 16.0 ℃/s to 28.2 ℃/s while those produced with a sand mold temperature of 25 ℃ exhibit a cooling rate range of 26.2 ℃/s to 58.5 ℃/s.

The directionally solidified superalloy DZ125 is widely used as turbine blades in aero-engines. This work investigates the influence of phosphorus（P）on the microstructure, mechanical properties and crack susceptibility of DZ125 alloy. The results indicate that P primarily segregates at grain boundaries in DZ125 alloy and has little effect on γ′ phases, γ+γ′ eutectic and carbides in the alloy. When P content reaches 0.008% （mass fraction, the same below） P-rich phases form in the interdendritic regions during casting, which subsequently dissolve back into the matrix during heat treatment.When the P content is no more than 0.0039%, P shows no obvious effects on the room-temperature tensile properties or the stress rupture life at 980℃/235 MPa. However, it has a significant impact on the stress rupture life at 760℃/805 MPa: the alloy with 0.0039% P exhibits a 37% decrease in stress rupture life at 760℃/805 MPa compared to the alloy with 0.0013% P, due to the segregation of P at grain boundaries weakens the grain boundaries. When the P content reaches 0.011%, the intergranular cracks appear in the DZ125 alloy hollow turbine blades during directionally solidified process. The main reason for the increase of crack susceptibility is excessive enrichment of P at grain boundaries and precipitation of P-rich phases nearby grain boundaries, which leads to grain boundary weakening and crack initiation.

Traditionally, the creep performance of superalloys are characterized under isothermal and constant-stress conditions. However, in the service environments of aero-engines, internal cooling introduces notable through-thickness temperature gradients within turbine blade materials. Consequently, examining the creep behavior of single-crystal alloys under such temperature gradients holds considerable engineering significance. This study conducts a series of temperature-gradient creep experiments based on a Ni₃Al-based superalloy. Temperature gradients of 10⁵ K/m and 5×10⁴ K/m are imposed. The results indicate that temperature gradients exert a substantial influence on specimens creep rupture life. Specifically, compared to isothermal creep, the application of a 10⁵ K/m gradient leads to an almost 46% extension in creep life, whereas a 5×10⁴ K/m gradient results in about 30% improvement. Fractographic and microstructural analyses reveal enhanced anisotropy on the fracture surface under temperature gradients. Furthermore, the oxidation behavior varies markedly across different temperature zones: the high-temperature region exhibits a denser, thinner oxide layer, whereas the low-temperature region displays a porous, thicker oxide layer. In the 10⁵ K/m gradient specimen, the low-temperature area exhibits a rafted γ′ structure, while the high-temperature area shows a de-rafted morphology, suggesting differing strain rates between these regions.

Stress rupture tests are conducted on DD10 alloy specimens with two distinct wall thicknesses at conditions of 1000 ℃/200 MPa and 1100 ℃/100 MPa. The stress damage characteristics of these specimens and the reasons for the thin-wall effect are analysisd. The findings reveal that, under both test conditions, the stress rupture life of thinner specimens is markedly shorter compared to thicker ones, indicating a pronounced thin-wall effect in DD10 alloy. Although the reduction in effective bearing area due to oxidation does expedite the creep process to some extent, the variation in effective stress increase across different wall thicknesses is minimal, within a range of just 6%. This suggests that the augmentation in effective stress stemming from oxidation is not the primary catalyst behind the thin-wall effect. Microstructural observations of the surface and longitudinal sections of the fracture reveal that, under both test conditions, the cavities and cracks in thinner specimens are smaller in size than those in thicker specimens. Furthermore, the relationship between the stress intensity factor（K） and crack length（l） indicates that, for cracks of equivalent size in specimens with varying wall thicknesses, thinner specimens exhibit a higher stress intensity factor at the crack tip, rendering the crack more prone to propagation. Consequently, thinner specimens have a shorter critical size for crack instability expansion. The disparity in this critical size among specimens with different wall thicknesses is pinpointed as a crucial factor contributing to the thin-wall effect.

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.

Heat treatment is the most critical thermal process determining the properties of powder metallurgy（PM）superalloy components, with FGH96 currently being one of the most prevalent PM Ni-based superalloys. This work investigates the effects of two distinct solution heat treatment cooling methods—full air cooling quenching and combined air-oil cooling quenching—on the microstructure and properties of FGH96 alloy ring parts. The results indicate that both cooling methods yield equivalent grain sizes, ranging from grade 6.5 to 7. Notably, full air-cooled rings exhibit more homogeneous distribution of secondary γʹ phase. In contrast, rings subjected to combined air-oil cooling exhibit coarser secondary γʹ phases, with reduced quantity on the inner side compared to the outer side, attributable to internally diminished cooling rate. During the later stage of quenching, ring parts undergoing full air cooling experience a slower cooling rate than those using combined air-oil cooling. Furthermore, fine γʹ phases, possessing sizes between the secondary and tertiary γʹ phases, precipitate along the grain boundaries using full air cooling method, leading to grain boundary strengthening. This enhances tensile strength but reduces elongation and plastic elongation at 68 h in high-temperature creep tests. Additionally, due to the more uniform cooling rate throughout the ring during full air cooling quenching, the surface residual stress reduces with more uniform distribution, thereby augmenting dimensional stability during subsequent machining processes.

Titanium alloy investment castings are widely used in the aerospace industry. During the manufacturing process, titanium is prone to reacting with the ceramic shell, which leads to defects such as shell cracking and casting deformation. Therefore, it is important to investigate the temperature distribution and deformation behavior during the sintering process of ceramic shell to improve the performance of the ceramic shell and enhancing the quality of casting. An advanced Monte Carlo method is employed to establish the radiative heat transfer model. Additionally, considering the impact of thermal damage, a coupled thermo-mechanical-damage constitutive model is established. A specialized simulation software is created through secondary development based on ABAQUS to investigate the sintering process of ceramic shell. Thermo-physical parameters of the ceramic shell are measured to provide data support for the simulations. The proposed models are experimentally validated using a flat-plate specimen, and experimental results agree well with the simulated outcomes. Using the developed software, a comprehensive study is conducted on the temperature distribution and deformation behavior of the ceramic shell in an annular-stepped specimen under various process schemes. The results indicate that a non-uniform temperature distribution during the sintering process is more likely to induce significant deformation and even cracking in the shells, particularly at structural protrusions. Moreover, as the sintering temperature rises, the decreased viscosity of the glassy phase in the ceramic shell will also intensify thermal stress accumulation and localized deformation. The simulation study on the temperature distribution and deformation behavior of the ceramic shell during the sintering process provides theoretical insights and technical support for optimizing the sintering process of the ceramic shell and improving the qualification rate of titanium alloy investment castings.

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.

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.

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.

With the rapid advancement of modern electronic and communication technologies, there is an increasing demand for high-performance electromagnetic wave（EMW）absorbing materials. Materials that combine lightweight properties, high-temperature resistance, and broadband absorption capabilities have become a growing research hotspot. This work proposes a novel strategy for fabricating ceramic metamaterials based on ultraviolet（UV）-curable hyperbranched polysilazane（UV-PSN） precursors. By introducing photosensitive groups into the ceramic precursor monomers and utilizing digital light processing（DLP） 3D printing technology, the synergistic regulation of microstructure and macroscopic morphology is successfully achieved. The fabricated SiCN ceramic metamaterials not only exhibit high-temperature resistance up to 1400 ℃ and tunable dielectric properties but also demonstrate excellent manufacturing precision. In addition, the unique hollow structure design significantly enhances the impedance matching performance of the overall SiCN ceramic material, achieving an effective absorption bandwidth of 3.4 GHz in the X-band. Furthermore, the overall weight of the SiCN ceramic metamaterials is reduced by 79.6% compared to solid structures. This study provides new design concepts and technical pathways for developing multifunctional EMW absorbing materials suitable for extreme environments.

Radar serves as the “eye” of aircraft, playing a crucial role in aircraft guidance and thus necessitating protection by radomes. Given that radar components are primarily positioned at the aircraft’s nose and work in a complex environment, radome materials must exhibit high wave transparency, rain erosion resistance, impact resilience, and antistatic properties. However, the prevailing radome material, glass fiber reinforced plastic composites, falls short in terms of rain erosion resistance and antistatic performance. Rain erosion and electrostatic accumulation can disrupt radar signal transmission, ultimately compromising flight safety. Consequently, the application of rain-erosion-resistant and antistatic coatings emerges as an effective protective measure. This paper reviews the characteristics and current research status of aircraft radome coating systems globally and domestically, while also projecting the development and research directions of coating materials. Initially, the paper analyses the performance requirements for coatings based on the unique service environment of aircraft radomes. It then delves into the structural characteristics, protection mechanisms, and international research advancements of rain-erosion-resistant and antistatic coating systems. Domestic research into aircraft radome coating materials has a relatively late onset. These coatings have evolved from inelastic formulations to polyurethane elastic coatings, with further refinements and optimizations to the polyurethane resin enhancing weather resistance. In the realm of antistatic coatings, ongoing challenges include balancing electrical conductivity and dielectric properties while ensuring coating performance stability. Conclusively, the paper briefly analyzes the development key point of aircraft radome coating materials. It points out for future in-depth research focusing on three areas: the correlation between coating material properties and environmental factors, the damage and failure mechanisms of coating materials, and the compatibility of multifunctional coating materials.

With the rapid development of detection technology, the demand for infrared stealth performance in weapons and equipment is increasing, especially the urgent need to suppress the infrared radiation signal of high-temperature components. Pt metal films have ultra-low infrared emissivity, However, due to the diffusion of metal films with matrix elements at high temperatures, the infrared emissivity increases significantly. Therefore, it is necessary to prepare a barrier layer with high temperature stability. An alumina thin film barrier layer is prepared using magnetron sputtering and electron beam vapor deposition processes, respectively. The microstructure, phase composition of alumina thin films prepared by different processes and variation of emissivity after magnetron sputtering Pt coating on alumina thin films are studied by SEM and XRD. The results indicate that the alumina films prepared by electron beam vapor deposition process have a stable crystal structure. After surface coating with Pt metal film, the initial infrared emissivity of the film is 0.16. After high-temperature treatment at 900 ℃ for 20 h, the infrared emissivity is 0.172. It has good high-temperature resistance and is expected to be applied as a barrier layer for high-temperature and low infrared emissivity films.

Based on hot compression tests of GH738 superalloy, encompassing deformation temperatures ranging from 980 ℃ to 1100 ℃ and strain rates of 0.001-0.1 s⁻¹, deformation activation energy（Q）, temperature-compensated strain factor（lnZ）, power dissipation efficiency（η） and instability factor（$ \xi (\dot{\varepsilon })$） are calculated. Subsequently, a response surface model is established, utilizing hot deformation processing parameters as input variables and targeting Q, lnZ, η and $ \xi (\dot{\varepsilon })$ as output metrics. This model facilitates the optimization of the superalloy’s heat deformation processing parameters. The results show that the superalloy’s flow stress exhibits considerable sensitivity to variations in these parameters, which significantly impact Q, lnZ, η and $ \xi (\dot{\varepsilon })$. Notably, the established response surface model demonstrates exceptional prediction accuracy, with average absolute relative errors of 0.494%, 0.564%, 0.919% and 13.484% for Q, lnZ, η and $ \xi (\dot{\varepsilon })$, respectively. Employing multi-objective optimization—aiming for low Q and lnZ coupled with high η and $ \xi (\dot{\varepsilon })$—the optimal deformation processing parameters are determined to within the range of 1092-1100 ℃ deformation temperatures and 0.001-0.0056 s⁻¹ strain rates. Microstructural analysis conducted under these optimized parameters further validates the accuracy of the multi-objective optimized results.