Bai Jialin, Yao Xiumin, Liu Xuejian, Huang Zhengren
State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
Center of Materials Science and Optoelectronic Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
Materials (Basel). 2025 Aug 30;18(17):4071. doi: 10.3390/ma18174071.
SiC nanowires (SiC), 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/SiN and SiC/SiN ceramics with different SiC phase morphologies were fabricated using a simple precursor impregnation and pyrolysis method. The Fe impurity content of the SiN 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/SiN 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/SiN covers the entire X-band. The porous SiC/SiN ceramics exhibit excellent electromagnetic wave absorption performance, demonstrating significant application potential for high-temperature environments.
碳化硅纳米线（SiC）因其优异的介电性能，有望成为高温吸收材料。然而，其高温吸收机制仍需进一步研究。因此，采用简单的前驱体浸渍和热解方法制备了具有不同SiC相形态的多孔SiC/SiN和SiC/SiN陶瓷。SiN粉末原料中的铁杂质含量显著影响SiC纳米线的生成。当SiC以纳米线形式存在时，纳米线导电网络带来的优异导电性导致材料的介电常数对温度有显著响应。当测试温度为室温时，SiC/SiN具有优异的吸收性能，在2.16 mm处最小反射损耗为-29.75 dB，在2.54 mm处有效吸收带宽为3.72 GHz。随着测试温度升高到300℃，SiC/SiN的有效吸收带宽覆盖整个X波段。多孔SiC/SiN陶瓷表现出优异的电磁波吸收性能，在高温环境下具有显著的应用潜力。
