With the rapid development of new aerospace vehicles, there are increasing demands for higher structural reliability and wideband microwave stealth requirements for the components operating under high-temperature condition. SiBCN based metastable ceramics exhibit good resistance to high temperature, thermal shock, ablation, long-term oxidation, and creep, showcasing great potential in the field of high-temperature structural microwave absorption. However, their ability to absorb electromagnetic waves is limited by low dielectric loss. In this study, the SiBCN-rGO ceramic fibers with good mechanical and microwave-absorbing properties were prepared using the wet spinning technology. Results showed that the as-prepared SiBCN-rGO ceramic fibers possessed porous structure, with porosity increasing with the increase of reduced graphene oxide (rGO) content. Additionally, both high rGO content and high fiber specific surface area promoted the crystallization of SiC within the amorphous matrix. The introduction of rGO significantly enhanced the tensile properties of the resulting ceramic fibers. As the mass fraction of rGO increased from 0 to 4%, the fibers’ elongation at break increased from 8.05% to 18.05%, and the tensile strength increased from 1.62 cN/dtex (0.324 GPa) to 2.32 cN/dtex (0.464 GPa). The increase of rGO content also reduced the electrical resistivity of the ceramic fibers. Moreover, as the rGO mass fraction increased from 0 to 4%, both the real and imaginary parts of the fibers’ dielectric constant decreased, while the loss tangent gradually increased. The SiBCN-rGO ceramic fibers with those containing 6% (mass fraction) rGO exhibited excellent wave-absorption performance, showing the minimum reflection coefficient of -50.90 dB at 9.20 GHz and an effective absorption bandwidth of 2.3 GHz, indicating promising applications in wave-absorbing ceramic matrix composites.

To further expand the application of advanced ceramic materials in helicopters, this paper reviews their application in helicopter structures both domestically and internationally. It emphasizes the technical maturity and development trends of various ceramic materials in helicopter specific structural applications, such as energy impact protection parts, energy conversion components, and corrosion protection areas. By comparing the gaps between domestic and international use of advanced ceramic materials in helicopter specific structures, the paper provides suggestions for the future development. Recommendations include the use of reaction-sintered contoured integrated opaque armor ceramics and polycrystalline transparent armor ceramics for the high-speed dynamic impact energy protection parts, cermet composite coatings compatible with epoxy resin composite substrates for the low-energy impact protection parts, and hybrid ceramic matrix composite/polymer matrix composite (HCMC-PMC) materials for the thermal shock protection parts. Additionally, multifunctional composite materials, such as high-performance miniature piezoelectric ceramic thin film functional devices and flexible hybrid electronic structures based on micro-piezoelectric ceramic materials, should be developed for the mechanical and electrical energy conversion components. Microwave-absorbing ceramic composites derived from polymer-derived ceramics that are compatible with epoxy resin composite substrates are recommended for the electromagnetic and thermal energy conversion components. Furthermore, high-performance abrasion-resistant and corrosion-resistant Sol-Gel coatings are suggested for the corrosion protection areas. It is also essential to establish a high-speed dynamic energy impact protection mechanism for helicopters, optimize the ballistic performance of protective materials, and develop advanced ceramic materials digital testing and verification technologies, represented by multi-functional composite materials for helicopter specific structures. These efforts will greatly shorten the application cycle of advanced ceramic materials and reduce the verification cost.

Absorptive materials, by absorbing electromagnetic wave energy, effectively mitigate electromagnetic interference through reduction or elimination of wave reflection. The electromagnetic parameters of materials determine their electromagnetic wave absorption performance. Traditional control strategies, such as adjusting filler ratio, changing macroscopic morphology, and regulating composite methods, have certain limitations to control their structure and cannot fundamentally alter their electromagnetic parameters, which severely hinders their further development. Now, micro-nanostructure design strategies can basically change electromagnetic parameters of the materials by altering their electrical conductivity, charge density and magnetic properties, showing significant advantages in controlling electromagnetic wave absorption capacity. However, the precise micro-nanostructure design and the mass production still face challenges to be overcome. Additionally, structure-property relationship between micro-nanostructures and electromagnetic wave response, and its underline mechanisms are still not fully understood. Herein, a comprehensive review on these relationships was introduced to elucidate the advantages of micro-nanostructure design strategies for regulating electromagnetic wave absorption capacity. Moreover, by introducing these strategies, such as element doping, surface effect modulation and nucleation-controlled growth, this review provides researchers with deep insights and theoretical guidance for modulating electromagnetic properties through micro-nanostructure design. Finally, the research progresses on electromagnetic performance modulation through micro-nanostructure design based on the case of quantum dots, nanocrystals and nanowires, as well as the current research status and prospects in the field of electromagnetic absorption were summarized, providing a theoretical foundation and strategic support for the development of micro-nanoparticles.

Polymer-derived SiCN ceramics benefiting from advantages of light mass and low coefficient of thermal expansion, have received wide attention in electromagnetic wave absorption field. However, the wave absorptive performance of SiCN ceramics needs to be further improved due to its monomer loss mechanism and insufficient temperature resistance. Enhancing their wave absorptive performance with the aid of multicomponent synergy is a feasible way, but still facing some challenges in preparation and wave absorption. In this work, four types of nanoceramics, SiHfCN, SiHfCN-C, SiHfCN-B, and SiHfCN-N were obtained by single-source modification of polysilazane combining different compounds. The results showed that SiHfCN generated HfO₂ and SiO₂ for up to 13.5% (in mass) oxygen content in the Hf source, resulting in the minimum reflection loss (RL_min) of only -13.8 dB and the effective absorption bandwidth (EAB) of only 0.42 GHz. Compared to SiHfCN, the co-modification of the Hf-containing polymer with C, B and N sources increased the interface and conductive phases of polymer-derived ceramics, real and imaginary parts of SiHfCN-C, SiHfCN-B, and SiHfCN-N gave rise to 1.4-1.8 and 2.7-3.9 times higher, respectively, with RL_min of -50.6, -57.3 and -63.5 dB, and EAB of 3.53, 3.99 and 4.01 GHz, showing a significant improvement in their wave absorptive properties. The SiHfCN-C inhibited the generation of HfO₂ for massive free carbon, which could enhance the conductivity loss. The SiHfCN-B generated B-N and B-C bonds, and precipitated nanorods of HfSiO₄ to provide more heterogeneous interfaces, increasing the polarization loss. The SiHfCN-N increased the content of N-C bond due to the introduction of abundant N, enhancing the dipole polarization loss, while the generated carbon nanosheets not only enhanced the conductivity loss but also provided rich interfaces, which improved the impedance matching and amplified the polarization loss, thus exhibiting excellent wave absorptive performance.

Developing novel low-dimensional materials for terahertz electromagnetic shielding and absorbing applications represents a critical research frontier. Their unique electrical, mechanical, and electromagnetic responses hold great potential in enabling more efficient solutions for electromagnetic shielding and absorbing. Two-dimensional transition metal carbides, nitrides, and carbonitride MXenes have already demonstrated excellent electromagnetic shielding and absorbing performance in the low-frequency spectrum. MXenes possess high conductivity, low density, and high flexibility, which are advantageous for future portability and integration of terahertz devices and systems. However, practical implementation of MXene-based terahertz electromagnetic shielding and absorption materials faces challenges in adhesion stability, environmental resilience, and high-temperature tolerance, hindering their suitability for aerospace and future next generation communication applications. Moreover, in terahertz frequency band, lacking more comprehensive and reliable electromagnetic scattering and absorbing measurement methods limits the development of THz shielding and absorbing materials. Extensive research efforts have targeted on these limitations, exploring fundamental architectural and theoretical aspects of prevalent electromagnetic materials. This review specifically highlights the terahertz electromagnetic shielding and absorption characteristics inherent in various MXenes and their compositions, such as Ti₃C₂T_x, Mo₂Ti₂C₃T_x, Mo₂TiC₂T_x, Nb₄C₃T_x, and Nb₂CT_x. Additionally, this review envisages the forthcoming challenges and prospects of MXenes as a pivotal electromagnetic shielding and absorbing material within the terahertz frequency band.

Advanced ink printing techniques, such as printing and coating, have overcome the limitations of traditional manufacturing methods, allowing for rapid prototyping of films and electronic devices with sophisticated structures and specific functions. These techniques hold enormous potential in wearable smart identification, energy storage, electromagnetic shielding and absorption, touch display, and so on. The key to printing advanced energy and electronic devices lies in the development of cutting-edge functional inks and their corresponding printing technologies. MXene, a family of two-dimensional compounds composed of transition metal carbides, nitrides, or carbonitrides, was discovered in 2011. MXene exhibits remarkable physical and chemical properties, including high conductivity, pronounced hydrophilicity, and diverse surface chemistry, which has garnered significant attention within the research community and made it particularly suitable as inks in printing applications. Conducting research on the printing behavior and mechanisms of MXene inks is crucial not only for achieving high-precision patterns but also for establishing a solid foundation for manufacturing techniques that can precisely create multiscale, multimaterial and multifunctional films, and electronic devices. This article begins with a brief discussion of MXene flakes’ synthesis and colloidal stability, followed by a detailed examination of its rheological characteristics, printable ink formulation, and printing methods. Additional, special attention is given to the latest advances of MXene ink in energy, health, and sensing applications. The perspective concludes with a summary of current research challenges and future directions in this area, offering new perspectives and insights for researchers.

Development of 5 G wireless communication and low-frequency radar detection has made low- frequency electromagnetic wave radiation a serious problem today. Although research on medium and high frequency band absorbing materials is now relatively mature, designing low frequency band absorbing materials remains a major challenge. Here, we designed a low-band composite absorbing material of 0.5-3 GHz based on the quarter-wavelength cancellation mechanism. A CIPs@Mn_0.8Zn_0.2Fe₂O₄-CNTs ternary composites were prepared by using a simple one-step hydrothermal method, which involved growing ferrite on the surface of carbonyl iron powder and carbon nanotubes. The influence of carbon nanotube content on the absorption peak frequency of the material was investigated. Experimental results show that carbon nanotubes enhances the material's attenuation coefficient by introducing additional interfacial polarization, dipole polarization and other loss mechanisms. Furthermore, coupling of high dielectric and high permeability enables the material to achieve better impedance matching in the low frequency band based on the quarter-wavelength cancellation mechanism. At a thickness of 4 mm, the reflection loss of the samples was obtained at 2.11 GHz and 1.75 GHz, with a -10 dB bandwidth of 1.70-2.70 GHz and 1.40-2.20 GHz, respectively. The composites exhibit excellent low-frequency absorption performance, endowing it highly suitable for applications helped by its simple preparation process and well low-frequency absorption. This research provides a new method for developing more effective low-frequency absorbing materials.

Two-dimensional transition metal carbon/nitride MXenes show promising applications in various fields due to their remarkable electrical and mechanical properties. Recently, the research of high performance MXenes nanocomposites (including one-dimensional fibers, two-dimensional films and three-dimensional blocks) has made remarkable progress. However, the mechanical properties are still far lower than the intrinsic mechanical properties of MXenes nanosheets, mainly due to the key scientific problems of voids, misalignment of MXenes nanosheets and weak interfaces. In order to solve the above problems, the intrinsic mechanical properties of MXenes nanosheets are firstly discussed in this work, then the development of high performance MXenes nanocomposites are summarized, and the latest research progress of high performance MXenes nanocomposites is discussed in detail, including how to eliminate void, improve the orientation of MXene nanosheets and enhance the interface interaction. Meanwhile, the applications of high performance MXenes nanocomposites in the fields of electric heating, thermal camouflage, electromagnetic shielding, sensing and energy storage are introduced. Finally, the challenges and future development directions of high performance MXenes nanocomposites are proposed.