掺Li_2O–B_2O_3–SiO_2玻璃低温烧结MgTiO_3–CaTiO_3陶瓷及其微波介电性能  

LOW-TEMPERATURE FIRING AND MICROWAVE DIELECTRIC PROPERTIES OF MgTiO_3–CaTiO_3 CERAMICS DOPED WITH Li_2O–B_2O_3–SiO_2 GLASS

作　　者：童建喜[1] 张启龙[1] 杨辉[1] 孙慧萍[1] 

机构地区：[1]浙江大学材料与化工学院,杭州310027

出　　处：《硅酸盐学报》2006年第11期1335-1340,共6页Journal of The Chinese Ceramic Society

基　　金：浙江省重点科技计划(2005C210387)资助项目。

摘　　要：研究了Li_2O–B_2O_3–SiO_2玻璃(LBS)对MgTiO_3–CaTiO_3(MCT)介质陶瓷烧结特性、相组成和介电性能的影响,分析了MCT陶瓷与银电极的共烧行为。结果表明通过液相烧结,LBS能有效降低MCT烧结温度至890℃。X射线衍射结果显示有Li_2MgTi_3O_8、硼钛镁石以及Li_2TiSiO_5等新相生成。随着LBS添加量的增大,陶瓷致密化温度和饱和体积密度降低,介电常数εr、品质因数与谐振频率乘积Q×f也呈现下降趋势,频率温度系数τf向负值方向移动。添加质量分数为20%的LBS的0.97MgTiO3–0.03CaTiO3陶瓷在890℃烧结4h,获得最佳性能εr=16.4,Q×f=11640GHz,τf=–1.5×10–6/℃。陶瓷与银电极共烧界面结合状况良好,无明显扩散。该材料可用于制造片式多层微波器件。The effects of Li2O-B2O3-SiO2 （LBS） glass addition on the sinterability, phase composition and dielectric properties of MgTiO3-CaTiO3 （MCT） ceramics were investigated. The co-firing behavior of dielectrics and Ag electrodes was also studied. It was found that LBS can effectively decrease the sintefing temperature of MCT to 890℃ by liquid phase sintering. Some new phases including Li2MgTi3O8, warwickite and Li2TiSiO5 were found by XRD analysis. With the increase of LBS content, the densification temperature and bulk density of MCT decrease, and the dielectric constant （ετ） and product of quality factor and resonance frequency （Qxf） values also decrease. The temperature coefficient of the resonance frequency （τf） shifts from positive to negative. The sample of 0.97 MgTiO3-0.03 CaTiO3 with 20% （in mass） LBS sintered at 890℃ for 4 h had the best dielectric properties： ετ=16.4, Qxf=1 1640 GHz, τf= -1.5×10^-6/℃. The co-firing interface between microwave ceramics and Ag electrodes has good cohesion and there is no obvious diffusion at the interface. The ceramic material is suitable for fabricating multilayer microwave chip devices.

关 键 词：钛酸镁-钛酸钙陶瓷 低温共烧陶瓷 介电性能 助剂 偏钛酸镁 

分 类 号：TQ174[化学工程—陶瓷工业]