摘要
通过传统的球磨工艺,以Co2O3为受主杂质和La2O3、Nb2O5、Bi2(SiO3)3为施主杂质,对BaTiO3系陶瓷进行掺杂。实验表明:Co2O3对BaTiO3陶瓷介电性能的影响跟La2O3、Nb2O5、Bi2(SiO3)3理论上产生的电荷n与Co2O3理论上产生的电荷p的比例有关:当n∶p>1时,介电常数-温度曲线趋于平缓,BaTiO3陶瓷呈现强铁电弥散性;介电损耗-温度曲线趋于平滑,随n∶p的减小,介电损耗总体减小;介电损耗-频率曲线呈现松弛极化损耗特性。当n∶p≤1时,BaTiO3陶瓷呈现较大的居里峰值,呈普通铁电体的性质;介电损耗-温度曲线出现较大的峰值;介电损耗-频率曲线表现为电导损耗特征。BaTiO3陶瓷晶粒的"核-壳结构"模型能较好解释这一现象。
A study on the influence of Co2O3 on BaTiO3 ceramics was conducted in order to investigate the mechanism by which Co2O3 improves dielectric properties.The experiment shows that the dielectric properties of BaTiO3 ceramics are related with the rate of donors n and acceptors p.The curves of permittivity and temperature give the ferroelectric relaxor characteristics,and the relationship between dielctric loss and temperature is expressed by diagonal line.And the curves of dieletric loss and temperature show the characteristics of relaxation polarization when n∶p>1.The curves of permittivity and temperature indicate the general ferroelectric behavior and a peak appears on every curve of dielctric loss and temperature.Moreover the curves of dieletric loss and temperature show the characteristics of relaxation polarization when n∶p<1.A model of core-shell is provided to explain the phenomena.
出处
《西华大学学报(自然科学版)》
CAS
2007年第5期81-84,共4页
Journal of Xihua University:Natural Science Edition
基金
西华大学人才基金资助项目(No.R0620109)