Nb2O5/Co2O3加入量对(Ba,Sr)TiO3基电容器陶瓷介电性能的影响

研究了Nb2O5/Co2O3加入量质量分数,Nb/Co(摩尔比)=0.8]不同对(Ba,Sr)TiO3(Barium strontiumtitanate,BST)铁电电容器陶瓷介电性能的影响,得到不同Nb2O5/Co2O3加入量与BST陶瓷性能的关系。借助扫描电镜(SEM)和X射线衍射仪(XRD)研究不同Nb2O5/Co2O3加入量对BST陶瓷显微结构和物相的影响,探讨了Nb2O5/Co2O3加入量对BST陶瓷性能影响机理。结果表明:当Nb2O5/Co2O3加入量为1.0%时,可得到满足Y5V特性、介电常数为3934、介质损耗为2.6%综合性能好的BST陶瓷。Nb2O5/Co2O3加入量对BST陶瓷性能的影响是通过细晶化、压抑展宽居里峰、改善介电常数温度特性、减少介电常数、形成杂相、形成“晶核-晶壳”结构等进行。

Effects of Nb2O5/Co2O3 Additive Amount on the Dielectric Properties of ( Ba, Sr) TiO3 Capacitor Ceramics

The effects of various Nb_2O_5/Co_2O_3 additive amount(mass fraction,Nb/Co mole ratio is equal to 0.8) on the dielectric properties of(Ba,Sr)TiO_3(Barium Strontium Titanate,BST) ferroelectric capacitor ceramics were investigated.The influence of various Nb_2O_5/Co_2O_3 additive amount on microstructure and structural phase of BST ceramics were studied by scanning electron microscope(SEM) and X-ray diffraction(XRD).The relationship between different Nb_2O_5/Co_2O_3 additive amount and the properties of BST ceramics was obtained and the mechanism was discussed.The results show that the BST ceramics having optimum comprehensive properties has been obtained,which the dielectric temperature property is suited for Y5V character,the dielectric constant is 3934 and the dielectric loss is 2.6%,while Nb_2O_5/Co_2O_3 additive amount is 1.0%(mass fration).The effects of Nb_2O_5/Co_2O_3 additive amount on the properties of BST ceramics are conducted by means of fining grain,repressing and broadening Curie peak,improving temperature character of dielectric constant,decreasing dielectric constant,forming impurity phase and coming into being"Core-shell" structure.