摘要
研究了乙炔黑/钛酸钡复合材料的烧结条件和介电性能.利用XRD、SEM和介电性能测试仪对材料的物相结构、微观形貌和介电性能进行了观察测定.分析结果表明,这种材料在空气中烧结时,其乙炔黑极易氧化挥发,难以形成钛酸钡/乙炔黑复相体系,但在烧结过程中,乙炔黑的分解挥发会在一定程度上增加液相的出现,促进陶瓷的烧结;在氮气保护下,乙炔黑可以完好地分布于钛酸钡陶瓷体中,获得结构致密的钛酸钡/乙炔黑复相陶瓷.较好的烧结温度范围为1200-1250℃.在渗流阈值附近,钛酸钡/乙炔黑复相材料介电常数值大大提高,当乙炔黑含量在0.8-2.0wt%范围内时,其介电常数达到35000以上,比纯钛酸钡提高约12倍,介电损耗可以控制在0.2-0.7之间,具有一定的使用价值。
The ceramic composite which has a super high dielectric constant was prepared by compounding and sintering Acetylene Black（AB） and BaTiO3 together in the protective atmosphere. Microstructure and morphology of the composite were measured by XRD and SEM, and the dielectric properties were measured by LCZ meter. The results indicate that the prepared samples, are much difficult to form BaTiO3/AB composites when sintering in air atmosphere and at high temperature, because AB is oxidated and volatilized under that case. But the calcination process is improved due to the formation of liquid phases with decomposition and volatilization of AB in the AB doped BT system, AB can however be distributed in the sintered BaTiO3 matrix perfectly when sintering in the protective atmosphere of N2. The BaTiO3/AB ceramic composite with dense structure is hence formed completely while calcining at the temperature range 1200℃ to 1250℃. The dielectric constant of the BaTiO3/AB composite is increased evidently around the percolation threshold. The super high dielectric constant of 35000 can be obtained in BaTiO3/AB composites when AB content between 0.8wt% and 2.0wt%, which is 12 times more than that of BaTiO3 without AB doping.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第5期1106-1112,共7页
Journal of Inorganic Materials
基金
国家自然科学基金(50372057
50332030)教育部高等学校博士学科点专项科研基金(20020335017)
关键词
钛酸钡/乙炔黑
复相材料
超高介电常数
渗流效应
BaTiO3/acetylene black
composite
super high dielectric constant
percolation behavior
