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采用固相合成法制备了(Ba1-αSr_α)4.8(Sm0.7La0.3)8.8Ti18O54(α=0.1～0.5)系陶瓷,表征了该陶瓷的相组成和显微结构,测试了微波介电性能。结果表明:α=0.3时,(Ba1-αSr_α)4.8(Sm0.7La0.3)8.8Ti18O54系陶瓷为单相的新钨青铜结构固溶体。α>0.3时,相继出现了第二相BaLa_2Ti_4O12和La0.66TiO2.993。随α的增加,(Ba1-αSra)4.8(Sm0.7La0.3)8.8Ti18O54系陶瓷的相对介电常数(εr)先增大后有所波动,品质因数(Qf)先增大后减小,谐振频率温度系数(τf)单调减小。α=0.3时,在1350℃烧结的陶瓷的微波介电性能最佳:εr=98.77,Qf=5 184GHz,τf=10.9×1-6/℃,优于不掺杂的BaO-Sm_2O3-TiO2陶瓷的。
Abstract：(Ba1-αSr_α)4.8(Sm0.7La0.3)8.8Ti18O54(α=0.1-0.5) ceramics were prepared by the solid state reaction.The phase compositions and microstructure were characterized.The microwave dielectric properties were also measured.A single solid solution with new tungsten bronze structure was observed in(Ba1-αSr_α)4.8(Sm0.7La0.3)8.8Ti18O54 ceramics whenα= 0.3.A secondary phase of BaLa_2Ti_4O12 and La0.66TiO2.993 appears subsequently whenα>0.3.The relative dielectric constant(εr) increased first,and subsequently shows a fluctuating curve with increasingαvalue.For the quality factor(Qf),the value ofαfirst increases and then decreases.Theαvalue exhibits a negative effect on the temperature coefficient of the resonance frequency(τf).The optimal dielectric properties are achieved in(Ba1-αSr_α)4.8(Sm0.7La0.3)8.8Ti18O54(α=0.3) ceramic with anεr value of 98.77,Qf of 5 184 GHz andτf of 10.9×10-6/℃,which is better than the case of BaO-Sm_2O3-TiO2 ceramic.
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基本信息:
中图分类号:TQ174.1
引用信息:
[1]谭颖,沈春英,丘泰.(Ba_(1-α)Sr_α)_(4.8)(Sm_(0.7)La_(0.3))_(8.8)Ti_(18)O_(54)陶瓷的微波介电性能[J].硅酸盐学报,2009,37(06):911-915.
基金信息:
国防研制资助项目。
2009-06-15
2009-06-15