【摘要】 采用溶胶-凝胶(Sol-gel)法制备了不同Ti/Ba比的钛酸钡纳米粉体及其陶瓷。通过XRD、SEM和TEM对钛酸钡粉体及陶瓷进行了表征,并测试了陶瓷的介电性能,研究了Ti/Ba比对陶瓷微观结构和介电性能的影响。结果表明:通过溶胶-凝胶工艺制备的纳米粉体主要为立方相钛酸钡,平均粒径约19~33 nm:随Ti/Ba比的增加,钛酸钡纳米粉体平均粒径呈先稍递减后增大的趋势,当粉体平均粒径大于30 nm吋,四方相在混合相中所占比例逐渐增大;Ti/Ba=1.01~1.03时,陶瓷中异常长大的晶粒较多,室温介电常数降低;1300℃烧结2 h的Ti/Ba=1.04的钛酸钡陶瓷具有较好的介电性能。更多还原

【Abstract】 The powders and the ceramics of barium titanate with various Ti/Ba molar ratios were prepared by sol-gel process.The powders and ceramics were characterized by XRD,SEM and TEM methods.The dielectric properties of the ceramics were determined.The influences of Ti/Ba molar ratio on the texture and dielectric properties were discussed.The results showed that the nanosized powders of 19³3nm can be prepared by sol-gel process.With increasing Ti/Ba molar ratio,the average crystallite sizes of the powders firstly reduced and then increased.When the average erystallite sizes above 30nm,the amounts of tetrahedron BaTiO₃ phase in the powders increased.The ceramics with Ti/Ba=1.01¹.03 showed abnormal grain growth and a decrease of room-temperature permittivity.The ceramics with Ti/Ba=1.04 sintered at 1300℃ for 2 hours had better dielectric properties.更多还原