摘要
以硅粉和炭黑为原料,利用燃烧合成法,在0.1MPa的N2气氛下合成了β-SiC粉体。对其进行拉曼光谱和SEM表征,结果表明:合成的SiC为含有C反位缺陷CSi和石墨态sp2C的富Cβ-SiC固溶体。添加剂聚四氟乙烯(PTFE)含量为10%时合成的SiC粉体为等轴状团聚颗粒,粒径约为0.2μm,随着PTFE添加量的增加,SiC粉体颗粒的平均粒径增大。在8.2~12.4GHz频率范围对所合成SiC的介电常数进行测试,发现15%PTFE时合成的SiC粉体具有较好的介电常数实部ε′、虚部ε″和介电损耗tanδ,对其微波损耗机理进行了讨论。
The powders of β-SiC were synthesized by combustion processing in 0.1 MPa N2 atmosphere using Si powder and carbon black as starting materials, and characterized with Raman spectra and SEM. Results show that the prepared SiC is C-enriched β-SiC solid solution, containing aitisite defects of Csi and graphite state of sp2C. The SiC powder synthesized with 10% polytetrafluoroethylene (PTFE) in the raw material is the agglomerate symmetric particle with the mean size of about 0.2 μm, and the mean size of the particle increases as the PTFE content increases. The permittivity and dielectric loss of the prepared SiC were determined in the frequency range of 8.2-12.4 GHz. It is found that the SiC powder synthesized with 15% PTFE in the raw material reveals better real part ε' and imaginary part ε" of permittivity and dielectric loss tanδ The mechanism of microwave loss has been discussed.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2009年第A02期9-12,共4页
Rare Metal Materials and Engineering
关键词
SiC
点缺陷
介电性能
燃烧合成
silicon carbide
point defects
dielectric properties
combustion synthesis