Dielectric properties of porous SiC/Si3N4 ceramics by polysilazane immersion-pyrolysis

查看全文 作　　者：Xiao [1,2]Lin;Hongyu [1,2]Gong;Yujun [1,2]Zhang;Jianqiang [1]Bi;Yurun [1,2]Feng;Yu [1,2]Liu;Shan [1,2]Wang 机构地区：[1]Key Laboratory for Liquid-Solid Structural Evolution&Processing of Materials of Ministry of Education,Shandong University,Jinan 250061,China;[2]Key Laboratory of Special Functional Aggregated Materials,Ministry of Education,Shandong University,Jinan 250061,China 出　　处：《Progress in Natural Science:Materials International》索引2019年第29卷第2期,共7页 基　　金：financially supported by the National Natural Science Foundation of China(No.51572154) 摘　　要：The SiC nanotubes were synthesized on porous Si3N4 matrix by polysilazane immersion-pyrolysis. The β-SiC and free C contents increased with the increasing dipping times, which cause some clear vibration and loss peaks of the dielectric constant patterns emerged at around 12.9 GHz and 14.7 GHz in the samples of 20 wt% and 30 wt%benzoic acid, respectively. The reflectivity of the obtained ceramics were -7 dB ^-10 dB from the frequency of 8 GHz–18 GHz, which means that the amount of 80%–90% electromagnetic wave could be attenuated. The ceramics containing 40 wt% benzoic acid showed the high loss, low reflectivity and a wide absorbing band,indicating the high absorbing efficiency and good dielectric properties. 关 键 词：SiC SI3N4 Dipping DIELECTRIC properties