孔隙率对三维针刺C/C复合材料电磁屏蔽性能的影响

Influence of porosity on the electromagnetic shielding properties of 3D C/C composites

摘要: 通过多次重复先驱体浸渍裂解(PIP)工艺过程,改变材料的孔隙率和体密度,制备不同孔隙率的三维针刺碳/碳(C/C)复合材料,并研究了在8.2~12.4GHz频率范围内(X波段)不同孔隙率C/C复合材料的电磁屏蔽效能。结果表明:适当降低孔隙率有利于提高C/C复合材料的总电磁屏蔽效能和电磁吸收屏蔽效能,当开气孔率为33.4%时,C/C复合材料具有最大的电磁屏蔽效能(40dB),且电磁吸收屏蔽效能(30dB)远大于电磁反射屏蔽效能(12dB),是极具潜力的高吸收低反射电磁屏蔽材料。

Abstract: 3D carbon/carbon (C/C) composite materials with different porosities and bulk densities were fabricated by repeated precursor infiltration and pyrolysis (PIP) process, and the electromagnetic interference shielding (EMI) effectiveness of C/C composites at 8.2-12.4GHz (X band) with different porosities were studied. The results indicate that both EMI absorption shielding effectiveness and the total EMI shielding effectiveness of C/C composites could be improved by reducing the porosity appropriately. When the open porosity is 33.4%, the C/C composite material shows a maximum shielding effectiveness of 40dB, and the EIM apsorption shielding effectiveness(30dB) is much higher than EMI reflection shielding effectiveness(12dB)). Porous C/C composite is one kind of excellent EMI shielding materials with high absorption and low reflection.