中文摘要：

以稀土氧化物EuzO3为添加剂，采用固相反应法制备了不同掺杂比例（x=0、0．2％、0．5％、1％（质量分数））的CaCu3Ti4O12（CCTO）陶瓷样品。采用X射线衍射仪（XRD）和扫描电镜（SEM）对掺杂样品的微观形貌变化进行测量分析；利用一直流高压电源测试样品的J-E非线性特征；利用Anglent4294型精密阻抗分析仪测试样品的电介性能。掺杂后样品的晶格结构并未发生明显的改变，但是平均晶粒尺寸减小，晶界处富Cu相消失；纯CCTO的XRD图谱中出现了富Cu相，掺杂样品的图谱中并未出现上述杂相；EueO3掺杂提高了样品内部的肖特基势垒高度，增加了势垒阻挡层的数目，使得样品的压敏电压和非线性系数明显提高，材料的压敏电阻性明显改善，电介频率稳定性增强。

英文摘要：

The CaCu3Ti4O12 ceramics doped by Eu2O3 with different dopant contents（x=0,0. 2%,0. 5%, 1% （wt%）） were prepared by the traditional solid-state reaction method. SEM and XRD were used in the structural studies of the samples; a high voltage measuring unit was used to determine the nonohmic（J-E） behaviors of the samples. Agilent 4294A precision impedance analyzer was used to measure dielectric properties. The results show that the crystal lattice structure of CCTO doped by Eu2O3 are similar to that of pure CCTO, but Eu2O3 dopping can decrease the the average grain size and can also deter the formation of Cu-enriched phase in the grain boundary. The second phase of CuO is presented in the XRD pattern of pure CCTO and disappears in that of the samples doped by Eu2O3; Eu2O3 dopping can enhance the height of the schottky barriers and increase the number of boundary barriers. This not only greatly raised the nonlinear coefficient and the threshold voltage of the CCTO varistors but also significantly improved the frequency stability of dielectric properties.