Ba(Zn_(1/3)Nb_(2/3))O_3--ZnNb_2O_6复相陶瓷的显微结构和介电性能

Microstructure and Dielectric Properties of Ba(Zn_(1/3)Nb_(2/3))O_3--ZnNb_2O_6 Composite Ceramics

采用传统电子陶瓷工艺制备Ba(Zn1/3Nb2/3)O3--ZnNb2O6(BZNZ)复相陶瓷,研究了Ba(Zn1/3Nb2/3)O3(BZN)含量对BZNZ陶瓷显微结构和微波性能的影响。结果表明,加入BZN提高了陶瓷的烧结温度,陶瓷为复相结构,除Ba(Zn1/3Nb2/3)O3与ZnNb2O6两种基体相外,有新相BaNb3.6O10生成。在微波频率下,随BZN含量增多,复相陶瓷的介电常数逐渐增大,品质因数Q×f值先增大后减小,谐振频率温度系数τf沿正方向移动。当BZN摩尔分数为30%时,陶瓷的综合性能最佳:相对介电常数εr=30.76,Q×f=29 600GHz,介电损耗tanδ=1.98×10--4,τf=--2.34×10--6/℃。

Ba（Zn1/3Nb2/3）O3-ZnNb206（BZNZ）＇ ceramics were fabricated via a conventional electric ceramic process. The effect of Ba（Znl/3 Nb2/3）Oa （BZN） on the microstructure and dielectric properties of BZNZ ceramics was investigated. The results show that the introduction of BZN increases the sintering temperature of BZNZ ceramics. A phase of BaNb3. 6 O10 appears in the ceramics besides ZnNb2 06 and Zn3 Nb2 08. The microwave dielectric properties of the BZNZ ceramics were measured. The die- lectric constant increases, the value of QX f firstly increases and then decreases and the temperature coefficient of resonance frequency ζf shifts to a positive value when the content of BZN increases. The ceramic with the BZN content of 30% （in mole） has the optimal dielectric properties, i. e. , ζf=30.76,Q×f =29 600 GHz,tan 3=1.98× 10-4 ,and ζf =-2. 34X 10-6/℃.