CaTiO_3对Mg_2B_2O_5微波介质陶瓷掺杂改性的研究

Study on Doping Modification Properties of Mg_2B_2O_5 Microwave Dielectric Ceramics by CaTiO_3 Additives

采用传统固相反应法制备CaTiO_3掺杂Mg2B2O5微波介电陶瓷。使用X线衍射仪(XRD)、扫描电子显微镜(SEM)和微波介电性能测试等手段,研究了CaTiO_3掺杂对样品微观结构和微波介电性能的影响。结果表明,Mg_2B_2O_5相和CaTiO_3相二者能够共存,随着CaTiO_3掺杂量的增加介电常数和谐振频率温度系数会增大,而品质因数会有所下降。当CaTiO_3的质量分数为5%时,样品在1 085℃烧结4h后获得了最佳微波介电性能,即介电常数εr=7.03,品质因数Q×f=42 221GHz,谐振频率温度系数τf=-2.8×10^(-6)℃-1。

The CaTiO3 doping Mg2B2O5 microwave dielectric ceramics were synthesized by the traditional solidstate reaction method. The effects of CaTiO3 doping on the microwave dielectric properties and micro structure of the samples were studied using XRD, SEM and microwave dielectric properties measurements. The results show that the Mg2B2O5 and CaTiO3 phases can coexist, and the dielectric constant and the temperature coefficient of resonant increase with the increase of the content of CaTiO3 while the quality factor slightly decreases. When the mass fraction of Mg2B2O5 is 5%, the CaTiO3 ceramics sample sintered at 1085 ℃ for 4 h shows optimal properties, that is,ε r=7.03, Q×f =42 221 GHz,τ f =-2.8×10 -^6 ℃^-1 .