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Wave-absorbing Si-C-N composite ceramic with bidirectional periodic pore structure and preparation method of wave-absorbing Si-C-N composite ceramic
The invention discloses a preparation method of wave-absorbing Si-C-N composite ceramic with a bidirectional periodic pore structure, which comprises the following steps: firstly, depositing Si3N4 ceramic with a certain thickness on carbon fiber cloth with a two-dimensional woven structure in situ by adopting a chemical vapor infiltration method to obtain a Cf/Si3N4 composite material; then carrying out oxidation treatment on the Si3N4 (C) porous ceramic to obtain Si3N4 (C) porous ceramic with an approximately hollow tubular braided structure; sequentially depositing a SiC nano interface layer serving as an electromagnetic wave loss layer, Si3N4 ceramic serving as an anti-oxidation protection layer and an impedance matching layer, and finally oxidizing and decarbonizing residual carbon fibers to obtain the Si3N4/(SiC/Si3N4/SiC)/Si3N4 composite ceramic with the bidirectional periodic pore structure. The Si3N4/(SiC/Si3N4/SiC)/Si3N4 composite ceramic prepared by the invention has a bidirectional periodic pore structure and a large number of wave-transmitting/absorbing nano heterogeneous interfaces and defects, when the thickness is only 2.45 mm, the average effective absorption efficiency of the composite ceramic in an X wave band exceeds-10dB, the strongest absorption reaches-24.5 dB, the preparation process is simple, the thermal stability of the material is good, the operability is strong, and the preparation method is suitable for industrial production. The preparation of the room/high-temperature synergistic wave-absorbing multiphase ceramic is facilitated.
本发明公开了一种具有双向周期孔结构吸波Si‑C‑N复相陶瓷的制备方法，首先采用化学气相浸渗法，在二维编织结构的碳纤维布上原位沉积一定厚度的Si3N4陶瓷，得到Cf/Si3N4复合材料；然后将其进行氧化处理，得到近空心管状编织结构的Si3N4(C)多孔陶瓷；接着依次沉积SiC纳米界面层作为电磁波损耗层，Si3N4陶瓷作为抗氧化保护层和阻抗匹配层，最后将残余的碳纤维氧化除碳得到具有双向周期孔结构的Si3N4/(SiC/Si3N4/SiC)/Si3N4复相陶瓷。本发明制备得到的Si3N4/(SiC/Si3N4/SiC)/Si3N4复相陶瓷存在双向周期孔结构、大量透/吸波纳米异质界面和缺陷，在厚度仅为2.45mm时，使得复相陶瓷在X波段的平均有效吸收效能超过‑10dB，最强吸收达到‑24.5dB，而且制备工艺简单、材料热稳定性好、可操作性强，有利于制备室/高温协同吸波复相陶瓷。
Wave-absorbing Si-C-N composite ceramic with bidirectional periodic pore structure and preparation method of wave-absorbing Si-C-N composite ceramic
The invention discloses a preparation method of wave-absorbing Si-C-N composite ceramic with a bidirectional periodic pore structure, which comprises the following steps: firstly, depositing Si3N4 ceramic with a certain thickness on carbon fiber cloth with a two-dimensional woven structure in situ by adopting a chemical vapor infiltration method to obtain a Cf/Si3N4 composite material; then carrying out oxidation treatment on the Si3N4 (C) porous ceramic to obtain Si3N4 (C) porous ceramic with an approximately hollow tubular braided structure; sequentially depositing a SiC nano interface layer serving as an electromagnetic wave loss layer, Si3N4 ceramic serving as an anti-oxidation protection layer and an impedance matching layer, and finally oxidizing and decarbonizing residual carbon fibers to obtain the Si3N4/(SiC/Si3N4/SiC)/Si3N4 composite ceramic with the bidirectional periodic pore structure. The Si3N4/(SiC/Si3N4/SiC)/Si3N4 composite ceramic prepared by the invention has a bidirectional periodic pore structure and a large number of wave-transmitting/absorbing nano heterogeneous interfaces and defects, when the thickness is only 2.45 mm, the average effective absorption efficiency of the composite ceramic in an X wave band exceeds-10dB, the strongest absorption reaches-24.5 dB, the preparation process is simple, the thermal stability of the material is good, the operability is strong, and the preparation method is suitable for industrial production. The preparation of the room/high-temperature synergistic wave-absorbing multiphase ceramic is facilitated.
本发明公开了一种具有双向周期孔结构吸波Si‑C‑N复相陶瓷的制备方法，首先采用化学气相浸渗法，在二维编织结构的碳纤维布上原位沉积一定厚度的Si3N4陶瓷，得到Cf/Si3N4复合材料；然后将其进行氧化处理，得到近空心管状编织结构的Si3N4(C)多孔陶瓷；接着依次沉积SiC纳米界面层作为电磁波损耗层，Si3N4陶瓷作为抗氧化保护层和阻抗匹配层，最后将残余的碳纤维氧化除碳得到具有双向周期孔结构的Si3N4/(SiC/Si3N4/SiC)/Si3N4复相陶瓷。本发明制备得到的Si3N4/(SiC/Si3N4/SiC)/Si3N4复相陶瓷存在双向周期孔结构、大量透/吸波纳米异质界面和缺陷，在厚度仅为2.45mm时，使得复相陶瓷在X波段的平均有效吸收效能超过‑10dB，最强吸收达到‑24.5dB，而且制备工艺简单、材料热稳定性好、可操作性强，有利于制备室/高温协同吸波复相陶瓷。
Wave-absorbing Si-C-N composite ceramic with bidirectional periodic pore structure and preparation method of wave-absorbing Si-C-N composite ceramic
一种具有双向周期孔结构吸波Si-C-N复相陶瓷及其制备方法
XUE JIMEI (author) / HOU ZEXIN (author) / LIU YUQIANG (author) / LI FEI (author)
2023-08-25
Patent
Electronic Resource
Chinese
IPC:
C04B
Kalk
,
LIME
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