MoSi2对Cf/SiC/Ni复合材料微观结构及吸波性能的影响

Effect of MoSi2 on Microstructure and Microwave Absorbing Properties of Cf/SiC/Ni Composites

以葡萄糖、Si粉、碳纤维为原料,镍为催化剂,采用水热反应-烧结法制备了Cf/SiC/Ni和Cf/MoSi2/SiC/Ni复合吸波材料。通过X射线衍射、扫描电子显微镜、波导法分别表征了Cf/SiC/Ni和Cf/MoSi2/SiC/Ni复合材料的相组成、微观结构和吸波特性。结果表明:Cf/SiC/Ni复合材料上生长的Si C纳米线稀疏且分布不均匀;厚度为1.5 mm时,在8.20 GHz处最小反射损耗为–14.61 dB,有效吸收带宽为0.23 GHz。Cf/MoSi2/SiC/Ni复合材料的碳纤维表面生长大量SiC纳米线,分布致密且均匀;厚度为2.0 mm时,在9.10 GHz时最小反射损耗为–34.14 dB,有效吸收带宽达2.18 GHz。与Cf/SiC/Ni复合材料相比,添加MoSi2的Cf/MoSi2/SiC/Ni复合材料吸波性能更好,说明MoSi2可有效改善Cf/SiC/Ni复合材料的微观结构及吸波性能。

The Cf/SiC/Ni and Cf/MoSi2/SiC/Ni composites were prepared by a hydrothermal reaction–sintering method using glucose,Si powder,and carbon fiber as raw materials and nickel as a catalyst,respectively.The phase composition,microstructure and absorbing properties of Cf/SiC/Ni and Cf/MoSi2/SiC/Ni composites were characterized by X-ray diffraction,scanning electron microscopy and waveguide,respectively.The results show that Si C nanowires are grown sparsely and unevenly in the Cf/SiC/Ni composites.The minimum reflection loss at 8.20 GHz is–14.61 dB,and the effective absorption bandwidth is 0.23 GHz when the thickness of the grown SiC nanowires is 1.5 mm.The massive SiC nanowires are grown densely and uniformly on the surface of carbon fiber of Cf/MoSi2/SiC/Ni composites.The minimum reflection loss is–34.14 d B at 9.10 GHz,and the effective absorption bandwidth is 2.18 GHz when the thickness of the grown SiC nanowires is 2.0 mm.Compared to Cf/SiC/Ni composites,the wave absorbing properties of Cf/MoSi2/SiC/Ni composites are improved.It is indicated that MoSi2 is a key factor improving the structural and absorbing properties of Cf/SiC/Ni composites.