MgO-Al_2O_3-SiO_2-B_2O_3对BaAl_2Si_2O_8结构与微波介电性能的影响

Effect of MgO-Al_2O_3-SiO_2-B_2O_3 on structure and dielectric properties of BaAl_2Si_2O_8

采用固相反应工艺,制备了Ba Al_2Si_2O_8-x(MgO-Al_2O_3-SiO_2-B_2O_3)(x=0%,1%,2%,3%,4%,质量分数)微波介质陶瓷。通过密度仪、XRD、网络分析仪等设备研究不同含量Mg O-Al_2O_3-Si O_2-B_2O_3(MBAS)玻璃相对Ba O-Al_2O_3-Si O_2(BAS)系介电材料结构及微波介电性能的影响。结果表明:MBAS玻璃相能有效促进六方钡长石转变为单斜钡长石,当x≥2%时,可以得到100%转变的单斜钡长石。随着MBAS玻璃相含量的增多,样品的密度、相对介电常数(ε_r)、品质因数(Q·f)和谐振频率温度系数(τ_f)增大。在x=2%,烧结温度为1410℃时,可获得综合性能相对较好的单斜钡长石,其介电性能:ε_r=6.02,Q·f=35 644 GHz,τ_f=-26.2×10^(-6)℃^(-1)。

Ba Al2Si2O8-x（Mg O-Al2O3-Si O2-B2O3）（x=0%,1%,2%,3%,4%,mass fraction）ceramics were prepared by solid state route.The crystal structure and microwave dielectric properties of Ba O-Al2O3-Si O2with different Mg O-Al2O3-Si O2-B2O3（MBAS）glass contents were studied by automatic density meter,XRD and network analyzer.The results showthat MBAS glass can greatly promote the phase transition of Ba Al2Si2O8 from hexacelisian to celsian.The transition can reach 100%when x≥2%.With the increasing of MBAS glass content,the density,relative permittivity andτfof Ba Al2Si2O8-MBAS ceramics increase.The Ba Al2Si2O8-x（ MBAS） sintered at 1410 ℃ shows a high Q·f of 35 644 GHz,εr of 6. 02 and τf of -26. 2×10（-6）℃（-1）at x = 2%.