在BaTiO3(BT)-Nb2O2-ZnO系统中引入金属Zn,对BT进行介电性能研究,以期获得低烧高介X7R陶瓷材料.研究发现,掺杂量很小时金属Zn主要与瓷料及空气中的O2反应,晶粒变化小,容温性能能满足要求;随着掺杂量的增加,过量的zn存在于瓷料中,使得壳层体积增大,而晶粒的增大,壳-芯体积失配,导致了介电常数迅速增加,容温性能严重恶化,改性机理可用掺杂后晶粒壳与晶粒芯体积分数的变化来解释.经配方和工艺优化后,在空气中于980℃下烧成的BaTiO3陶瓷材料的主要性能指标达到:ε298K＞2700,tgδ≤1.O%,ρ≥10Ω·cm,在-55～125℃范围内最大电容量变化率不超过士15%,可用于制备低烧高介X7R多层陶瓷电容器.
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