MoS₂ nanoflower decorated porous Si₃N₄ ceramics were prepared by a combination of vacuum infiltration and hydrothermal reaction. Excellent electromagnetic wave absorption performance was achieved by constructing MoS₂-Si₃N₄ heterostructures.

SiC nanowires (SiC_nw), due to their excellent dielectric properties, are promising high-temperature absorbing materials. However, the mechanism of their high-temperature absorption still requires further research. Therefore, porous SiC_nw/Si₃N₄ and SiC/Si₃N₄ ceramics with different SiC phase morphologies were fabricated using a simple precursor impregnation and pyrolysis method. The Fe impurity content of the Si₃N₄ powder raw material significantly affects the generation of SiC nanowires. When SiC exists in the form of nanowires, the excellent conductivity brought by the conductive network of the nanowires causes a significant response of the material’s permittivity to temperature. When the test temperature is room temperature, SiC_nw/Si₃N₄ has excellent absorption performance with a minimum reflection loss of −29.75 dB at 2.16 mm and an effective absorption bandwidth of 3.72 GHz at 2.54 mm. As the test temperature increases to 300 °C, the effective absorption bandwidth of SiC_nw/Si₃N₄ covers the entire X-band. The porous SiC_nw/Si₃N₄ ceramics exhibit excellent electromagnetic wave absorption performance, demonstrating significant application potential for high-temperature environments.

Silicon carbide (SiC) ceramics with Y₂O₃-Er₂O₃ as sintering additives were prepared by spark plasma sintering (SPS). The effects of sintering temperatures and Y₂O₃-Er₂O₃ contents on the microstructure, thermal conductivity, electrical, and mechanical properties were investigated. The increasing of sintering temperatures promoted the densification of SiC ceramics, thus increasing the thermal conductivity and electrical resistivity. With the increase of the sintering additive contents, the electrical resistivity increased due to the formation of the electrical insulating network; and the thermal conductivity first increased and then decreased, which was related to the content and distribution of the secondary phase among the SiC grains. The SiC ceramics sintered at 2000 °C with 9 wt.% Y₂O₃-Er₂O₃ exhibited higher electrical resistivity and thermal conductivity, which were 4.28 × 10⁹ Ω·cm and 96.68 W/m·K, respectively.

With 6wt% total carbon additive amount, the microstructure and properties of pressureless solid-state sintered SiC(SSiC) were studied with different carbon sources and carbon source adding ratio. It is found that SSiC ceramics with inorganic carbon (carbon black) as carbon source have finer SiC grains and lower density. As the carbon additive amount derived from organic carbon source (phenolic resin) increases, the grain size of SiC grains in SSiC ceramics increases, the distribution of carbon phase in the ceramics is more homogeneous, the density and the mechanical properties of SSiC ceramics increase. When the carbon additive amount derived from organic carbon source is 3.0wt%, the ceramics with highest density have the largest elastic modulus, which is up to 486 GPa, the fracture toughness of it is 4.65 MPa·m1/2. When the carbon additive amount derived from organic carbon source is over 3.0wt%, the abnormal grain growth of SiC grains appears in the ceramics, the fracture strength and toughness further increase. At the same time, the thermal diffusion coefficient of SSiC ceramics with different carbon sources and adding ratio is also discussed

Mesocarbon microbead-silicon carbide (MCMB-SiC) composites were prepared by hot-press sintering (2100 °C/40 MPa/1 h) with two different graphitized MCMBs as the second phase, which exhibited good self-lubricating properties. The effects of the graphitization degree of the MCMBs on the microstructure and properties of the composites were investigated contrastively. The results showed that the composites that added raw MCMBs with a low degree of graphitization had excellent self-sintering properties, higher densities, and better mechanical properties; by comparison, the composites that added mature MCMBs with a high degree of graphitization, which has regular and orderly lamellar structures, not only had good mechanical properties but also exhibited a lower and more stable dry friction coefficient (0.35), despite the higher wear rate (2.66 × 10⁻⁶ mm³·N⁻¹·m⁻¹). Large amounts of mature MCMBs were peeled off during the friction process to form a uniform and flat graphite lubricating film, which was the main reason for reducing the dry friction coefficient of the self-lubricating composites and making the friction coefficient more stable.