SiC纳米线改性C/C复合材料的制备及其电磁波吸收性能研究

Fabrication and Electromagnetic Wave Absorption Performance of C/C Composites Modified by SiC Nanowires

C/C复合材料因低密度、耐高温等特性在航空航天材料方面具有很广泛的应用,通过改性的方法提高该类材料的电磁波吸收性能有望拓宽其应用领域。本文以酚醛树脂、Si和SiO_(2)粉体,以及催化剂二茂铁为原料,采用先驱体浸渍裂解法制备C/C复合材料,然后通过化学气相反应法在C/C复合材料中生成SiC纳米线(SiC_(nw)),制备出SiC_(nw)改性C/C复合材料(SiC_(nw)/C/C)。研究了C/C和SiC_(nw)/C/C复合材料的结构与性能,探讨了SiC_(nw)含量对C/C复合材料电磁波吸收性能的影响。结果表明,通过本方法可在C/C复合材料中成功引入具有核壳结构的SiC_(nw),并且随着SiC_(nw)含量增加,C/C复合材料的电磁波吸收性能显著提升。当SiC_(nw)含量为15.4%(质量分数)时,SiC_(nw)/C/C复合材料在厚度为2.07 mm处的最小反射损耗值为-38.02 dB,明显低于同类其他材料,表现出优异的电磁波吸收性能。本文研究制备的SiC_(nw)/C/C复合材料可为高性能碳/陶复合材料的制备提供技术和理论支撑。

C/C composites have a wide range of applications in aerospace materials due to their low density,high temperature resistance and other characteristics.Improving the microwave absorbing performance of these materials through modification methods is expected to broaden their application fields.In this paper,C/C composite,SiC nanowire(SiC_(nw)),and SiC_(nw) modified C/C composite were fabricated by precursor infiltration and pyrolysis method,and chemical vapor reaction method using phenolic resin,Si,SiO_(2) and catalyst ferrocene as raw materials.The microstructures and properties of C/C and SiC_(nw)/C/C composites were studied,and the influence of SiC_(nw) content to electromagnetic wave absorption performance of C/C composites was discussed.The results show that SiC_(nw) with core/shell structure is successfully introduced into C/C composite,and the SiC_(nw)/C/C composite exhibits excellent electromagnetic wave absorption performance with the increasing of SiC_(nw) content,and the minimum reflection loss of SiC_(nw)/C/C composite with 15.4%(mass fraction)SiC_(nw) is-38.02 dB with a thickness of 2.07 mm,significantly lower than those of other materials.This work provides a technical and theoretical basis for the preparation of high-performance carbon/ceramic composites.