Modeling for the electromagnetic properties and EMI shielding of C-f/mullite composites in the gigahertz range
Modeling for the electromagnetic properties and EMI shielding of C-f/mullite composites in the gigahertz range
复制标题
千兆赫范围内 Cf/莫来石复合材料的电磁特性和 EMI 屏蔽建模
DOI：
10.1016/j.jeurceramsoc.2020.03.031
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发表时间：
2020
影响因子：
5.7
通讯作者：
Zhou Wei
中科院分区：
文献类型：
--
作者：
Xia Xiaodong;Li Yang;Long Lan;Xiao Peng;Luo Heng;Pang Liang;Xiao Xiazi;Zhou Wei
研究了放电等离子烧结Cf/莫来石复合材料在GHz频段（8.2-12.4 GHz）的电磁性能和电磁屏蔽效能。实验结果表明，CF/莫来石复合材料具有优异的电磁性能和高值的EMI屏蔽效能（近40 dB）与1.65vol%的碳填料在2 mm的厚度。我们定量表征的微观结构特征的贡献，整体EMI屏蔽效能使用基于细观力学的均匀化模型。电磁干扰屏蔽效能在阈值前随着Cf体积浓度的增加而增强。EMI屏蔽效能相对于AC（交流电）频率的增加趋势可以归因于在高千兆赫范围内的增强的导电性。结果表明，填料和频率相关界面效应是获得优异的Cf/莫来石复合材料电磁性能的关键。研究结果可为陶瓷基复合材料高温电磁屏蔽器件的设计提供指导。
The electromagnetic properties and EMI shielding effectiveness of Cf/mullite composites via the spark plasma sintering were intensively investigated in the gigahertz range (8.2–12.4 GHz). Experimental results have revealed excellent electromagnetic properties and a high value of EMI shielding effectiveness (nearly 40 dB) for Cf/mullite composites with 1.65vol% carbon fillers at thickness of 2 mm. We quantitatively characterize the contributions of microstructural features to overall EMI shielding effectiveness using a micromechanics-based homogenization model. The EMI shielding effectiveness enhances with respect to the Cfvolume concentration before the threshold. The increasing trend of EMI shielding effectiveness with respect to AC (alternating current) frequency can be attributed to enhanced conductivity at high gigahertz range. It is demonstrated that filler and frequency dependent interface effects are essential to obtain excellent electromagnetic properties of Cf/mullite composite. The present research can provide guidances for the design of ceramic-based composites applied in high-temperature EMI shielding devices.