Structure and Microwave Absorbing Property of Polycarbosilane Derived Silicon Carbide Ceramic
Structure and Microwave Absorbing Property of Polycarbosilane Derived Silicon Carbide Ceramic
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DOI：
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发表时间：
2012
影响因子：
0.7
通讯作者：
D. Dong
中科院分区：
文献类型：
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作者：
D. Dong
采用聚碳硅烷（PCS）在800 ~ 1 ~ 200℃热解法制备了SiC陶瓷。利用SEM、XRD和拉曼光谱对游离碳的形貌、晶相和微观结构进行了表征。测试了样品的直流电导率。利用矢量网络分析仪，在8.2 ~ 12.4 GHz（X波段）频率范围内，采用矩形波导法测量了PCS-SiC陶瓷的复介电常数。基于传输在线理论，计算了样品的微波吸收特性。结果表明：随着热解温度的升高，PCS-SiC陶瓷的直流电导率、介电常数实部和虚部均增大；由于极化和损耗的增强，微波吸收性能得到了改善。
SiC ceramic was fabricated through pyrolyzing polycarbosilane(PCS) at 800-1 200 ℃.The morphology,crystal phase and micro structure of free carbon were characterized by SEM,XRD and Raman spectrum,respectively.The DC conductivity of samples was tested.The complex permittivity of SiC ceramics derived from PCS(PCS-SiC) were measured by the method of rectangular waveguide using vector network analyzer in the frequency range of 8.2-12.4 GHz(X band).Based on transmission-line theory,the microwave absorbing properties of samples were calculated.The results show that DC conductivity,real and imaginary parts of permittivity increase with the evolution of pyrolysis temperature due to graphitization of free carbon in PCS-SiC ceramic.And,the microwave absorbing properties were improved due to enhancement of polarization and loss.