【摘要】 在BaTiO₃（BT）-Nb₂O₅-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:ε_298K>2700,tgδ≤1.0%,ρ≥10¹¹Ω·cm,在-55～125℃范围内最大电容量变化率不超过±15%,可用于制备低烧高介X7R多层陶瓷电容器。更多还原

【Abstract】 In this study,Zn dust is doped into the BaTiO₃（BT）-Nb₂O₅-ZnO system in order to obtain theX7R materials with high dielectric capacity sintered at low temperature.The experiment results reveal that,when the amountof Zn dust is small,Zn reacts with O₂ to produce ZnO.It comes hardly into the grain core,and△C/C（-55～+ 125℃）≤±15%.As more Zn dust is added,the dielectric capacity is very high,but△C/C（-55～+125℃）≤±15%cant be got The BaTiO₃ ceramics sintered at a temperature as low as 980℃in air atmosphere have such satisfieddielectric properties asε_298k>2700,tgδ≤1.0%,ρ≥10¹¹Ω·cm and△C/C（-55～+125℃）≤±15%.This material isvery promising for the preparation of X7R LTCCs.更多还原