摘要
将聚丙烯腈基预氧化纤维编织布在真空烧结炉中以10℃/min速率升温到650℃、700℃、750℃、800℃和850℃进行2h保温碳化处理。在固定碳化温度为650℃的情况下,保温10min、2h和4h后随炉冷却至室温。研究了真空碳化处理温度和保温时间对聚丙烯腈基预氧化碳纤维结构、电导率和介电性能的影响,结果表明,经真空碳化处理后,纤维电导率随温度的升高先增大后减小。当碳化温度为650～800℃时,纤维的介电常数实部(ε′)和虚部(ε″)都随碳化处理温度的升高而增大,且虚部的增大速度高于实部的增大速度。当碳化温度高于750℃后,在8.2～12.4GHz内纤维介电常数随频率的增大而减小。当碳化处理温度达到850℃时,纤维的介电常数相对于800℃时有所减小。在650℃,经过不同保温处理的纤维布,随保温时间的延长,纤维的介电常数实部和虚部都增大。根据以上研究结果,可以为制定以经适当碳化处理的纤维布为吸收体的吸波材料提供有效参考。
PAN-based carbon fibers are heated at 650℃, 700℃, 750℃, 800℃ and 850℃ in vacuum sintering furnace, respectively. The carbon fibers are also treating in different soaking time（10min, 2h and 4h） at 650℃. The microstructure of the carbon fibers after heat treatment are characterized by scanning electron microscopy（SEM） and the dielectric properties are determined in the frequency range of 8. 2-12. 4GHz. Results indicate that at 650-800℃, the real part（ε＇） and imaginary part（ε＂） of permittivity of the prepared carbon fibers increase and then decrease with heat treatment temperature increasing, and it shows the better dielectric frequency dispersion. Above 750℃, the dielectric constant decreases with heating temperature increasing in the range of 8. 2-12. 4GHz. At 850℃, the dielectric constant is lower than at 800℃. After treating at 650℃ and different soaking time, the real part（ε＇） and imaginary part（ε＂） of permittivity of the prepared carbon fibers increase with soaking time extension. The results can be a reference for preparing absorbing material.
出处
《材料导报》
EI
CAS
CSCD
北大核心
2010年第18期47-49,共3页
Materials Reports
基金
凝固技术国家重点实验室(西北工业大学)自主研究课题资助(KP200901)
关键词
预氧化碳纤维
碳化处理介电常数频散效应
stabilized fiber, carbonization, dielectric content, frequency dispersion
