The effects of two different deformation processes（process 1 and process 2） on the micro-structure and mechanical properties of reduced activation ferrite/martensite （RAFM） steel （Fe-0.21C-11.76Cr-1.41W-0.20V-0.17Ta-0.63Si-0.51Mn-0.015N， mass fraction/%） tubes are studied. The results show that when the rolling deformation of process 1 gradually increases from 44% to 66%， the tubes’ martensitic matrix transforms into fine ferritic matrix， the yield strength（σ_y） increases from 302 MPa to 407 MPa， the elongation（El） decreases from 28.6% to 25.8%， and the tensile strength（σ_U） remains basically unchanged. The matrix microstructure of process 2 （deformation amount 53%-57%） tubes also undergoes the transformation from martensite to ferrite， but due to the relatively small deformation amount， complete recrystallization is delayed， and σ_y decreases from 487 MPa to 364 MPa， and El increases from 23.9% to 36.3%. The tubes of two processes are subjected to the same forward and tempering treatments after final rolling with 44% and 66% deformation respectively. The microstructure of the finished tubes shows that carbide particles are evenly distributed on the matrix of lath martensite， and their mechanical properties at room temperature are equivalent（σ_y=590-597 MPa，σ_U=810-817 MPa，El=20.7%-22.8%）. However， the high-temperature mechanical properties of the finished tubes of process 2 （σ_y=357 MPa，σ_U=380 MPa，El=16.3%） are slightly lower than that of process 1 （σ_y=383 MPa，σ_U=446 MPa，El=21.6%）.

This study addresses the high-temperature sealing challenges in aero-engines by analyzing the effects of wall thickness， compression ratio， and cyclic compression cycles on the elastic performance of U-shaped metal seals. The optimal parameter combination is determined through systematic investigation. Additionally， a dedicated high-temperature gas tightness testing apparatus is developed to evaluate airtight performance， with a derived leakage rate calculation formula providing quantitative analysis. The results demonstrate that the elastic recovery rate decreases with increased wall thickness， higher compression ratios， or greater numbers of compression cycles. At 650 ℃， all three tested wall thicknesses maintain over 90% recovery rate after 50 compression cycles， with the 0.5 mm configuration showing superior elastic characteristics. Leakage rate exhibits negative correlation with temperature and contact stress， while displaying positive linear dependence on pressure differentials. Notably， the 0.5 mm seal achieves 50% lower leakage at 650 ℃ compared to room temperature. Enhanced wall thickness or compression ratio improves airtightness by elevating interfacial contact stress.

A novel auxetic columnar honeycomb structure is introduced， in which four honeycomb structures of identical dimensions are designed by varying the number of unit cells. The effects of unit cell number on the mechanical behaviour and energy absorption performance of the honeycombs are investigated through impact experiments and finite element numerical simulations. The energy absorption performance is compared with the specific absorption energy of aluminum honeycombs of different masses. The results demonstrate that the honeycombs exhibit a unique compression-torsion coupling deformation mechanism during impact. The torsional motion of cell walls redistributes the internal forces， effectively absorbing and dissipating impact energy， thereby improving energy absorption efficiency. Further analysis reveals that the number of unit cells significantly affects the mechanical performance of the honeycombs， enhancing plateau stress and specific energy absorption， although compression displacement decreases. A comprehensive mechanical performance analysis indicates that HM4-8 demonstrates the optimal impact performance and energy absorption efficiency， making it suitable for high-efficiency energy absorption and impact protection applications. This study provides new insights into the optimized design of honeycomb structures， with significant engineering value， especially in fields requiring lightweight designs and high impact resistance.

Nanomaterials with combined photothermal-chemodynamic therapy （PTT-CDT） offer significant advantages in cancer treatment， yet designing and fabricating such multifunctional nanomaterials remains challenging. In this study， cuttlefish ink （M） is used as a core， onto which a layer of CuO is grown， successfully constructing the M@CuO composite multifunctional nanomaterial. The results show that the M@CuO exhibits a spherical shape with a nanoparticle size of 128.2 nm and demonstrates excellent photothermal conversion efficiency （η_T=47.6%） under near-infrared light irradiation. Additionally， the M@CuO shows a strong Fenton effect at room temperature （25 ℃）， and the Fenton reaction rate can be further enhanced by the photothermal effect， with the reaction rate at 45 ℃ being 2.3 times that at 25 ℃ under the same conditions. In vitro cell experiments reveal that M@CuO has good biocompatibility and can effectively kill tumor cells through combined PTT-CDT. Therefore， M@CuO provides an effective strategy for developing multifunctional nanomaterials with PTT-CDT synergistic therapy.

C/C composites， with low density， high specific strength， stable high-temperature mechanical properties and excellent thermal shock resistance， are one of the candidate materials for core components under extreme conditions such as hypersonic vehicle thermal protection systems and solid rocket motor nozzles. However， C/C composites are prone to oxidation above 400 ℃ and suffer from poor ablation resistance over 2000 ℃. Conventional single coating or matrix modification methods have limited protective effects， seriously restricting their long-term service reliability in extreme environments. Based on the “coating-matrix integration” modification idea， ceramic phases can be synergistically distributed inside and on the surface of C/C matrix to form an integrated matrix-surface protection structure， breaking through the performance bottleneck of traditional single modification technologies. This paper systematically reviews current thermal protection technologies for C/C composites， summarizes the preparation process， thermal protection performance and mechanism of coating-matrix integrated modified C/C composites， analyses existing research bottlenecks and future directions， and provides ideas for the design and application of ultra-high temperature and long-life carbon-based composites.

Mesophase pitch-based carbon fibers （MPCF） possess excellent properties， such as high modulus and high thermal conductivity， making them key strategic materials for national defense security and advanced equipment development. However， their oxidation behavior in high-temperature aerobic environments remains poorly understood. This study investigates the oxidation behaviors and the evolution of mechanical and thermal properties of two types of MPCF， namely split-structured （CF-A） and round-structured （CF-B）， in both carbonized （1600 ℃） and graphitized （3000 ℃） states. The results show that CF-A-1600 exhibits preferential core oxidation during the 600 ℃ oxidation process， leading to a tensile strength retention of only 34.93%， which is lower than that of CF-B-1600 （51.79%）. Conversely， the CF-A-3000 achieves tensile strength retention of 79.64% and thermal conductivity retention of 94.36%， respectively， higher than those of CF-B-3000 （77.46% and 90.93%）. For carbonized MPCF， the oxidation behavior is dominated by diffusion-controlled reactions， where structural morphology plays a decisive role， and CF-B fibers exhibit superior oxidation resistance. For graphitized MPCF， oxidation behavior is governed by chemical-controlled reactions， in which intrinsic crystallite activity becomes dominant. For comparison， CF-A fibers show superior performance due to their better-developed crystallites and consequently higher oxidation activation energy. This study reveals the coupled mechanism between structural morphology and intrinsic crystallite activity of MPCF， providing a theoretical reference for reliability assessment and material optimization design of MPCF and their composites in extreme thermal service conditions.

To address the strength-ductility trade-off dilemma of high-oxygen powder metallurgy （PM） titanium alloys， two types of near-α titanium alloys （880-PE1 and 880-PE2） with α/β_t composite lamellar microstructure and oxygen mass fraction of 0.36% are fabricated via the combination of sintering and hot extrusion process. The crystal size and morphological characteristics are analyzed by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The crystallographic orientation features are examined through X-ray diffraction （XRD） macro-texture and electron backscatter diffraction （EBSD） micro-texture analysis. The relationships between microstructure and mechanical properties and deformation mechanisms are studied by combining room-temperature tensile tests and dislocation bright-field imaging observations. The results show that the 880-PE1 specimen exhibits no obvious micro-texture. Cracks initiate at grain boundaries of α phases during plastic deformation， resulting in a low elongation to fracture of only 8.9%. The 880-PE2 specimen develops a micro-texture with the 〈0001〉 direction of α grains aligned parallel to the extrusion direction. This unique micro-texture can effectively activate pyramidal 〈c+a〉 dislocations， which move via wavy slip and give rise to an extraordinary increase in work-hardening rate. Additionally， lamellar distortion and grain-boundary deformation compatibility are effectively promoted， and the initiation of intergranular cracks is suppressed simultaneously. Ultimate tensile strength of the 880-PE2 specimen reaches 1070 MPa，and the elongation to fracture increases to 22.0%， achieving synergistic improvement of strength–ductility.

Lithium ceramics （e.g.，Li₄SiO₄，Li₂TiO₃），as core tritium breeder materials， possess high lithium density， excellent thermal stability， and irradiation resistance. Traditional manufacturing methods such as extrusion-spheronization and melt-spraying face challenges including poor particle size uniformity， low crush load，and structural simplicity. As an advanced manufacturing technology， 3D printing offers innovative solutions for the precision forming of lithium-based tritium breeding ceramics in nuclear fusion reactors. Vat photopolymerization-based 3D printing enables the integrated fabrication of complex tritium breeding units （e.g.， honeycomb structures， porous frameworks），significantly improving structural precision， mechanical properties， and tritium release efficiency. This article systematically reviews the material properties， powder preparation processes， and limitations of conventional forming techniques for lithium ceramics， with a focus on the technical advantages and application prospects of vat photopolymerization 3D printing in achieving "structure-property synergy" manufacturing， as well as the multi-precursor-based generative shaping and material-forming method. Finally， future research directions are also proposed to address current technical challenges.

As modern high-end manufacturing increasingly trends towards miniaturization and multifunctionality， achieving high-quality joining of dissimilar materials has encountered severe technical bottlenecks. Addressing this challenge， nano-multilayer films have emerged as a highly promising technological pathway for realizing low-temperature， highly reliable bonding， owing to their pronounced size effects and high-density interfacial structures. This review focuses on immiscible nano-multilayer films of the Cu/X （X=W， V， Mo， Ta， Nb） refractory metal systems， systematically elucidating the thermal stability evolution mechanisms governed by interfacial microstructures， as well as the intrinsic mechanisms that modulate mechanical properties and irradiation responses. Furthermore， it summarizes the recent research progress on their applications as high-performance brazing fillers or interlayers in brazing and diffusion bonding， highlighting their critical roles in mitigating residual stress in joints and suppressing the formation of brittle intermetallic compounds. Finally， it points out that future research should focus on the multi-scale computational modeling of spatial interfacial transport mechanisms and interfacial evolution mechanisms under multi-field coupling. Overcoming the high-temperature thermal stability bottleneck of this system is also identified as a key direction to advance its engineering applications.

Laser cladding uses a high-energy laser to rapidly melt cladding materials with the substrate surface， forming a metallurgically bonded coating upon solidification. It is a key technology for producing high-performance surface coatings and remanufacturing metallic components. Recently， laser cladding has evolved from a surface coating technique into a comprehensive process integrating coating fabrication， repair of damaged parts， and additive manufacturing， showing great potential in new material development. This review first elaborates the metallurgical characteristics of laser cladding metals， then highlights process innovations in four directions： high efficiency， hybridization， specialization， and intellectualization. It further addresses the role of laser cladding in material development and fabrication， systematically reviewing research progress on conventional alloys， high-entropy alloys， amorphous alloys， metal matrix composites， and functionally graded materials， and summarizing their strengthening mechanisms and typical applications. However， challenges remain for laser cladding fabricating materials， including incomplete non-equilibrium solidification theories， lack of quantitative process-microstructure-property models， and inadequate monitoring and evaluation techniques. Future efforts should prioritize data-driven intelligent optimization， novel material system design， extreme-environment adaptability， and integration of multi-energy-field hybrid processes and combined process chains.