氧化物掺杂ZnO-Ba_(0.8)Sr_(0.2)TiO_3复合陶瓷的制备及电性能研究

Preparation and electrical properties of oxide doped ZnO-Ba_(0.8)Sr_(0.2)TiO_3 composite ceramics

采用固相法制备了氧化物掺杂ZnO-Ba0.8Sr0.2TiO3复合陶瓷,并利用X射线衍射仪和扫描电子显微镜对其晶相及微观形貌进行了观测;另外,研究了氧化物掺杂对陶瓷介电性能及压敏性能的影响。结果表明,当掺杂摩尔分数为0.50%的Bi2O3和0.50%的Sb2O3时,陶瓷在室温下的εr为36402,tanδ为0.065;在此基础上继续掺入0.25%的MnO和0.35%的Cr2O3,陶瓷的非线性系数α为5.4,漏电流IL为1.5×10–6A/mm2,压敏电压为3.0V。Bi2O3、Sb2O3、MnO和Cr2O3掺杂使ZnO-Ba0.8Sr0.2TiO3复合陶瓷的介电性能和压敏性能同时得到了有效提高。

Oxide doped ZnO-Ba0.8Sr0.2TiO3 composite ceramics were prepared by the solid state method. The crystal phase and micro-morphology of the ceramics were studied using XRD and SEM. The effects of oxide doping on the dielectric properties and varistor properties of the ceramics were also investigated. With the doping of 0.50% Bi2O3 and 0.50% Sb2O3（mole fraction）, the dielectric constant εr and dielectric loss tanδ of the ceramics at room temperature are 36 402 and 0.065, respectively; while 0.25% MnO and 0.35% Cr2O3 （mole fraction） are further introduced, the nonlinear coefficients α, break down voltage V and the leakage current density IL of the ceramics reach 5.4, 3.0 V and 1.5×10–6 A/mm2, respectively. Our test results clearly show that both the dielectric properties and varistor properties of the ZnO-Ba0.8Sr0.2TiO3 ceramics are improved with the doping of Bi2O3, Sb2O3, MnO and Cr2O3.