Y2O3掺杂对钛酸锶钡基陶瓷结构及介电性能的影响

摘要

In this paper, (1-x)Ba 0.2 Sr 0.8 Ti 0.98 Zn 0.04 O 3+xY 2 O 3(x=0,0.02,0.025,0.03)ceramic samples which based on 4at% ZnO-doped Ba0.2Sr0.8TiO3 (BST-Zn) ceramics were prepared by the conventional solid-state reaction technique. The effect of Y2O3-doped on microstructures and dielectric properties of the BST-Zn simples were studied systematically. The results show that: (1) With doping suitable amount of Y2O3 maximum contents, the simples’ cell volume increases and grain size decreases;(2) It is found that the dielectric constant is 885 and the dielectric loss is 0.024, when doped 2% Y2O3 in BST-Zn ceramic at 10Hz frequency; (3) with the the Y2O3 doping, BST-Zn’s dispersion phase transition turn into the polarization glass transition phase transition in low temperature area, and two relaxation processes have been found at the area of 250K and 350K.%采用固相反应方法制备出（1-x）Ba 0.2Sr0.8Ti0.98Zn0.04O3+xY2O3（x=0，0.02，0.025，0.03）陶瓷材料，并研究Y2O3掺杂对BST-Zn陶瓷样品结构和介电性能的影响，得到以下结论：（1）一定量的Y2O3掺杂，可使BST-Zn陶瓷的晶胞体积增大，晶粒尺寸减小；（2）频率为10Hz时，当掺入2%Y 2 O 3时，ε'最大值可达到885，此时介电损耗为0.024；（3）Y 2 O 3掺入使得低温的弥散相变转化向极化玻璃化转变，并在250K和350K附近出现新的弛豫过程.