氟化钙掺杂对钛酸锶钡陶瓷结构和介电性能的影响  

Effects of CaF_2 Additions on the Dielectric and Tunable Properties of Barium Strontium Titanate Ceramics

作　　者：刘珊珊[1] 赵玉珍[1] 王希林[1] 周和平[1] 

机构地区：[1]清华大学新型陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《稀有金属材料与工程》2015年第2期403-406,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(50572050)

摘　　要：研究了Ca F2掺杂对钛酸锶钡(Ba0.6Sr0.4Ti O3,BSTO)陶瓷的结构和介电性能的影响。采用传统烧结工艺制备了Ca F2掺杂的BSTO陶瓷,对其晶体结构、微观形貌和介电性能进行了研究。XRD结果显示,Ca F2掺杂BSTO陶瓷为钙钛矿结构,当掺杂量≥3%(质量分数)时,基体中出现第二相Ba Ca Ti O4。添加少量Ca F2(0.5%)可明显减小晶粒尺寸,随掺杂量继续增加,晶粒尺寸变化不明显。Ca F2掺杂降低了BSTO陶瓷的介电常数和介电可调性,减小了其介电损耗,提高了材料的综合使用性能。Barium strontium titanate ceramics（Ba0.6Sr0.4Ti O3, BSTO） doped with CaF2 were prepared using the conventional mixed oxide techniques. The phase structure, microstructure and dielectric properties of the samples were studied. The XRD patterns show the BSTO ceramics doped with CaF2 belongs to perovskite phase. A secondary phase Ba Ca Ti O4 is observed in the samples with excessive CaF2additives（≥3 wt %）. The grain size of BSTO is decreased greatly by small additions of CaF2（0.5%）, and then it is increased slightly with the increase of CaF2 content. The Curie temperature of 0.5wt% CaF2 doped BSTO is reduced to around –40 oC and remains the same with more CaF2 additives. The dielectric constant and the dielectric loss of the samples are reduced by CaF2 additives. For 1.5 wt% CaF2 doped samples, the dielectric constant is reduced to 1072, the microwave loss at 100 k Hz is 1.4×10–4 and the value of tunability is 6.6% with the external DC field 1.6 k V·mm-1.

关 键 词：钛酸锶钡 介电常数 介电可调性 Ca F2掺杂 

分 类 号：TQ174.1[化学工程—陶瓷工业]