Arc directed energy deposition technology has become an important technical direction for near-net forming of large aluminum alloy components due to its advantages of high deposition efficiency and high material utilization. However, there are some problems in the deposition process of 2319 aluminum alloy, such as residual pores, non-uniformity of layered structure and anisotropy of mechanical properties, which restrict its engineering application. In this paper, a hammer forging assisted arc directed energy deposition method was proposed. The effects of interlayer hammer forging and synchronous hammer forging on the forming quality, microstructure, porosity defects and mechanical properties of 2319 aluminum alloy were systematically studied. The results show that the synchronous hammer forging introduces 32.91% plastic deformation in the high temperature deposition zone, the porosity of the sample decreases by 77.48%, the average grain size is refined by 48.81%, the precipitated phase changes from coarse network to dispersed particle, the crystal texture is significantly weakened, and the synergistic improvement of microstructure refinement and densification is realized.

As modern radar detection systems evolve towards multi-band, ultra-wideband, and multi-base station collaborative detection modes, traditional stealth technologies relying solely on surface coatings are no longer sufficient to meet the stringent requirements of future aircraft for broadband, lightweight, and multi-functional integration. Additive manufacturing technology, with its extremely high degree of geometric design freedom and multi-material forming capabilities, provides a revolutionary solution to overcome the physical limits of traditional radar-absorbing structures, driving the transformation of stealth technology towards a “structure–function integration” paradigm. This paper systematically reviews the latest research progress of additive manufacturing technology in the field of broadband radar absorption for aircraft, deeply reviews the radar-absorbing material systems suitable for additive manufacturing, the principles and characteristics of mainstream additive manufacturing processes and further discusses engineering application examples of achieving multi-functional synergy of “load-bearing, stealth and thermal protection” through macro-micro cross-scale design. Finally, it summarizes the current challenges and the core directions for future development in the field of broadband radar absorption.

Super-aligned carbon nanotube stacked film (SACNT–SF) exhibits exceptional thermal insulation performance over a wide temperature range, owing to its nanoscale tube diameter, highly anisotropic porous structure, ultralow density, high extinction coefficient of sp² carbon, and excellent thermal stability. Based on prior foundational research, this article systematically introduces the fundamental properties of SACNT–SF and its thermal insulation mechanisms across broad temperature ranges, while further exploring the material’s potential in engineering applications. SACNT–SF possesses excellent flexibility and moldability, enabling conformal wrapping on complex-shaped surfaces through a filament winding process. To extend the applicability of SACNT–SF, an alumina protective layer was deposited via atomic layer deposition, significantly enhancing the material’s operating temperature and anti-ablation performance in air. By integrating SACNT–SF as a thermal insulation layer into a miniature ultra-high-temperature tubular furnace, low-power operation at 110 W was achieved under a working temperature of 3000 ℃. The outstanding performance of SACNT–SF under extreme high-temperature conditions offers new solutions for the development of next-generation thermal protection materials in aerospace and related fields.

LaSi₂-modified ZrC–TiC coatings were prepared on C_f/SiBCN composites by brushing, curing and sintering in an inert atmosphere. The effects of LaSi₂ content on microstructure, phase evolution and oxyacetylene ablation behavior at 2500 ℃ were investigated. LaSi₂ improved powder dispersion and sintering densification. The coating containing 20% (volum fraction) LaSi₂ showed the best overall performance, with the mass and linear ablation rates reduced by about 72% and 75%, respectively, compared with the unmodified coating, while the back-side temperature rise rate was about 3.1 ℃/s. After ablation, a dense glass-ceramic protective layer composed of ZrO₂, TiO₂, ZrTiO₄, zircon/titanium silicates, SiO₂ and La oxides was formed, accounting for the enhanced thermal protection behavior. In this study, LaSi₂ was introduced into ZrC–TiC coating for the first time to improve the ultra-high temperature ablation protection performance. The three-stage synergistic mechanism of LaSi₂ through ‘dispersion optimization-sintering densification-composite oxide layer construction’ was clearly revealed. At the same time, the contribution of surface SiO₂ glass phase and ZrSiO₄/TiSiO₄ crystallized skeleton to erosion resistance was systematically analyzed, which provided a new strategy for the design of ultra-high temperature thermal protection coatings.

Hypersonic vehicles operating under extreme thermal environments impose more demands on thermal protection materials. Transition metal diboride ceramics are the materials of choice due to their excellent high-temperature stability. Much effort has been aimed at improving the oxidation resistance. High-entropy design enables the joint solubility of ions with a large ionic radius difference; thus it has been proposed to incorporate rare earth elements in diborides aiming at enhance oxidation resistance. In this work, high-entropy diboride（Zr_0.2Hf_0.2Nb_0.2Sc_0.2Yb_0.2）B₂ was synthesized in the combination of the boron/carbothermal reduction reaction with spark plasma sintering. The oxidation behavior was systematically investigated over the temperature range of 1400–1600 ℃ focusing on the variation of oxidation products and the microstructure of oxide scale. It has been revealed that with the formation of Sc₂O₃·Yb₂O₃·HfO₂·B₂O₃ glass and rare earth borate（ScYb）BO₃, the volatilization of B₂O₃ was effectively retarded. The synergistic oxidation effect associated with rare earth and transition metal elements facilitated the formation of co-stabilized c-（Zr,Hf）O₂ and, fluorite（ZrHfNbScYb）O_2–x. The well-established the multicomponent skeletal MO₂ and glassy B₂O₃ exhibited significantly high temperature capability and hindered oxidation behavior. It is expected to provide the compositional design strategy for oxidation-resistant high-entropy diborides.

(Gd_0.9Yb_0.1)₂Zr₂O₇ (GYbZ) exhibits superior high-temperature phase stability and low thermal conductivity, qualifying it as an ideal material for ultra-high-temperature thermal barrier coatings for aeroengine turbine blades operating above 1300 ℃. Electron-beam physical vapor deposition (EB–PVD) is the mainstream fabrication method for such thermal barrier coatings. The investigation examines the impact of target-evaporation current, deposition temperature, and sample rotation speed on GYbZ coating morphology. At 0.8 A evaporation current, GYbZ coatings form coarsened columnar grains with dense secondary dendrites. At 1.2 A, grain size decreases and dendrites shorten. Low deposition temperature or slow rotation speed induces fine, dense, and uneven columnar grains, while higher temperature or faster rotation speed increase grain size and reduces size variation.

In this study, using ZrB₂-modified phosphate slurry as the matrix and alumina fiber as the reinforcement, fiber-reinforced zirconium pyrophosphate matrix composites were prepared by prepreg lamination, hot press curing, and high-temperature treatment. First, the formation mechanism of zirconium pyrophosphate matrix was analyzed through phase characterization of the composite material before and after high-temperature treatment. Second, the thermal resistance performance and variation patterns of the composite materials under repeated heating were studied through oxy-acetylene ablation tests and 1200 ℃ thermal shock tests, and the bending properties of the composites after thermal shock testing were characterized. The results show that after undergoing 20 cycles of oxy-acetylene ablation at a heat flux of 2.4 MW/m², the average of linear ablation rate and mass ablation rate of the composites are 0.0009 mm/s and 0.0010 g/s. After 20 cycles of 1200 ℃ thermal shock testing, the thickness change rate of the material is 1.7%, the mass change rate is 3.5%, and the bending strength retention rate is 82.2%.

To address the issue of cracking in the melt welding of Ti₂AlNb and 42CrMo steel shafts in aero-engine turbine rotors, a method was proposed to add a V interlayer between the Ti₂AlNb ring and the steel rod, and to use a two-pass laser welding technique to join the Ti₂AlNb/42CrMo steel heterogeneous socketed joints. The V interlayer forms discrete weld seams with the base metal on either side, leaving a un-melted V metal between them. The influence of welding passes and the thickness of the V interlayer on the residual stress was analyzed by finite-element simulation. Under the optimal process, the interface bonding quality of both weld seams is good, with no obvious welding defects. Microstructural analysis results indicate that the V interlayer effectively reduced a large amount of miscibility of Fe and Ti elements in the weld zone, thereby suppressing the formation of Fe–Ti intermetallic compounds. Under the high cooling rate of laser welding, the 42CrMo/V weld zone mainly consists of (Fe, V) solid solution, with a small amount of σ–FeV intermetallic compounds formed. The Ti₂AlNb/V weld zone mainly consists of (β–Ti, V) solid solution. The shear strength of the Ti₂AlNb/42CrMo heterogeneous socketed joint reaches 176 MPa, with fracture occurring along the V/42CrMo fusion line and in unmelted V layer, exhibiting ductile fracture characteristics.

Compared with traditional thermosetting composites, high-performance thermoplastic composites possess superior properties such as better impact damage resistance, environmental and medium resistance, easy repairability, and recyclability. Additionally, they are compatible with efficient and large-scale production. In recent years, their application advantages in the field of aviation manufacturing technology have become increasingly prominent. In response to China’s transformation demands for aviation composite material technology towards high efficiency, green development, and low cost, this paper conducts a technical decomposition of the EU’s “Clean Sky 2” program projects, focuses on reviewing the “Multifunctional Fuselage Demonstrator” (MFFD) project under this program, and systematically analyzes the material system selection and manufacturing process integration technology system of the project. The aim is to, by sorting out the material and manufacturing technology practices of the MFFD project, provide theoretical references and application insights for material selection, process optimization, and technological innovation of high-performance thermoplastic composites in aviation and related application fields, thereby promoting the further application of high-performance thermoplastic composites in the field of aviation manufacturing technology.

Carbon panel/aluminum honeycomb sandwich structures are of significant application value in aerospace structures due to their lightweight and high-load-bearing characteristics. The need for cost control in manufacturing and the requirement for extended service life have driven the innovation of structural repair technologies. In response to the demands for the assembly of large-sized components and the repair of composite materials, this paper focuses on the design and process development for panel splicing and sandwich structure splicing. The results indicate that laminated plates with 100 mm double-sided reinforcement exhibit a 1.5% increase in tensile strength and a 131% improvement in tensile modulus. For sandwich structure panel splicing, external reinforcement outperforms internal reinforcement. The core shear stress after external reinforcement is slightly higher than that of the un-repaired monolithic panel, with a bending stiffness of 699 N·m², representing a 78% enhancement compared to the monolithic panel. The spliced and reinforced sandwich structure demonstrates excellent appearance and defect-free adhesive quality, meeting the thermal vacuum test requirements under the same conditions as non-spliced products. Thus, this research introduces and substantiates a practicable process for the splicing and reinforcement of composite sandwich panels. The developed methodology supplies a viable technical route conducive to the economical production and operational upkeep of substantial aerospace assemblies, bearing considerable practical merit in furthering the goals of mass reduction and durability enhancement in structural engineering.

When industrial robots are applied to the milling process of aerospace structural components, insufficient rigidity of the robotic arm can easily induce low-frequency chatter problems. To address this issue, a Tuned Mass Damper (TMD) was employed to suppress the low-frequency chatter in robotic milling. Through combined theoretical modeling and experimental fitting, the modal frequency and damping ratio characteristics within the low-frequency range at the robot-end were investigated. The dynamic equations governing the robot end with an attached TMD were derived, and the influence mechanisms of key parameters on the vibration suppression effectiveness were analyzed. A pendulum TMD with adjustable stiffness stability was designed. Modal tests were conducted to characterize the relationship between its natural frequency and suspension length, leading to the formulation of a stiffness pre-adjustment methodology. Robotic milling experiments were performed both with and without the attached pendulum TMD. Comparative spectral analysis of vibration signals conclusively demonstrated the effectiveness of the pendulum TMD in suppressing vibrations during the robotic milling process.

Aircraft icing severely threats flight performance and poses safety hazards. Electrothermal anti-icing/de-icing system demonstrates considerable potential owing to their structural simplicity, design flexibility, and precise controllability, etc. With the development of heating elements, the system enables integrated structural-functional design and manufacturing, thereby enhancing the system integrity. This work developed heating elements based on spray coated carbon nanotubes (SCCNTs), which are co-embedded with glass fiber reinforced plastics serving as electrical insulating layers into carbon fiber reinforced polymer composite structures via a single-step curing. This process yields integrated composite leading edges with inherent anti-icing/de-icing functionality. Two structures with distinct ply sequences were designed and fabricated, with their electrothermal properties at ambient temperature and anti-icing/de-icing performance in an icing wind tunnel evaluated. Key findings reveal: (1) The conductive paths formed jointly by spray coated CNTs (SCCNT) and carbon fibers exhibit exceptional stability; (2) Heat transfer of the composite displays significant anisotropy; (3) Overheating risks can be mitigated through optimized thermal protection design; (4) Compared to the symmetric layup, strategic outward positioning of the heating layer can reduce the de-icing time and energy consumption by about 50%.

Based on the primitive hexagonal honeycomb (HH) structure, four enhanced configurations were designed. Under a condition of equal mass, GH4169 honeycomb specimens were fabricated using Selective Laser Melting (SLM). Their deformation modes and energy absorption characteristics were compared. The results show that the Body-Centered Cubic reinforced Honeycomb (BCCH) exhibits superior mechanical performance in both the X1 and X2 directions. Its yield strength and maximum force per unit volume reach twice those of the primitive HH. The elastic modulus in the X1 direction increases by 33%, and the compressive strength improves by approximately 200%. Regarding energy absorption, efficiency in the X2 direction is generally higher than in the X1 direction. The BPEH structure with an “H-shaped” symmetric arrangement demonstrates more uniform stress transmission. Although the Face-Centered Cubic reinforced Honeycomb (FCCH) has lower strength, its peak energy absorption efficiency is up to 81.60%, and its energy absorption efficiency is 25% higher than that of the HH structure. This study systematically evaluated the multidirectional mechanical and energy-absorbing behaviors of the structure under the condition of equal mass by the synergistic design strategy of shape, topology and lattice, which provides an innovative design paradigm and experimental basis for the performance controllable lightweight porous structure in the field of aerospace.

As the application areas of titanium alloys continue to expand, the diverse usage locations and service environments impose increasingly higher demands on the comprehensive performance. Alloying with various elements is an effective strategy for tailoring and optimizing the overall performance of titanium alloys. Based on the latest research progresses in the field of titanium alloy, this paper reviews and summarizes the influences of common alloying elements, including α–stabilizing elements (Al, O), β–stabilizing elements (Mo, V, Nb, Fe), neutral elements (Zr, Sn), and rare earth elements (RE) on the microstructure evolution and comprehensive performance. The intrinsic microscopic mechanisms by which it affects properties such as solid solution strengthening, grain refinement, dislocation strengthening, and deformation twinning are discussed. This review covers classic theories, latest design methods, and new research progresses in the field of titanium alloys, and look into the future development directions of titanium alloys. The current paper aims to provide new insights for the compositional design, microstructural control, and significant improvement of the properties of advanced titanium alloys.