锶掺杂的钛酸钡陶瓷制备及介电性能

Preparation and Dielectric Properties of Ba_(1-x)Sr_xTiO_3 Ceramic

钛酸钡作为一种高介电材料,在相变温度120℃附近具有较大的介电常数,为了更好应用于电子陶瓷材料中,需添加锶、锆、硅等掺杂物降低其相变温度至室温附近。本文用固相反应法制备了多种比例锶掺杂的钛酸钡陶瓷(Ba1-xSrxTiO3)。在不同频率下对其介电性能与相变温度做了对比研究。研究结果表明:一定比例锶掺杂能提高钛酸钡陶瓷的有效介电常数,同时随着掺杂比例增加可使相变温度向低温方向移动。x=0.3的锶掺杂比例使钛酸钡的相变温度移至室温附近,介电常数高于6 000,满足了一般电容器的工作环境要求。

Near the phase transition temperature 120 ℃,the dielectric constant of barium titanate is large. In order to be well applied in electric ceramics,the phase transition temperature needs to decrease to the room temperature through doping Sr,Zr,Si and so on. Barium titanate ceramics( Ba1- xSrxTiO3)doped with different rates of Sr were prepared through the solid-state reaction. The dielectric properties and the phase transition temperatures were studied with different frequencies. The results show that barium titanate ceramics with certain percentage of doping strontium improve the dielectric constant. At the same time,the phase change temperature is shifted to lower temperature with the doping ratio increasing. When x = 0. 3,the phase transition temperature is shifted to the room temperature with dielectric constant larger than 6 000,which may meet the requirements of capacitor.