在钛酸锶钡与质量分数为 6 0 %的MgO混合的基础上 ,进行了La2 O3 掺杂的系统研究 .随La2 O3 掺入量的增加 ,BST MgO材料的晶面间距先变大后变小 .掺杂适量的La2 O3 可降低BST MgO复合材料高频损耗 ,同时保证适中的介电常数 ,但过量的La2 O3 掺杂使得材料的介电常数降得很低 .当La2 O3 掺杂量为w(La2 O3 ) =0 .2 %时 ,BST MgO材料的介电常数为 84 .9,损耗为 0 .0 0 6 (2 .9GHz) ,介电常数可调率达 1 4 .3% (2 9.7kV/cm) .利用电介质理论分析了La2 O3 对BST MgO材料介电性质的改性机理 Based on the mixing of barium strontium titanate with 60% MgO, the La 2 O 3 doping system was studied systematically.With the increase of La 2 O 3 content, the interplanar spacing of BST MgO first becomes large and then changes The doping amount of La2 O3 can reduce the high frequency loss of BST MgO composites, meanwhile ensure the proper dielectric constant, but the excess La2 O3 doping makes the material low dielectric constant.When La2O3 doping The dielectric constant of BSTMgO was 84.9 for w (La2O3) = 0.2%, the loss was 0.06 (2.9GHz), the dielectric constant adjustable rate was 14.3% (2 9.7kV / cm). The dielectric properties of La2O3 modified BST MgO materials were analyzed by dielectric theory