摘要
目前国内外对εr范围在40～80左右的中介电常数微波介质陶瓷体系的研究还很缺乏。为适应现代微波通讯技术发展需求,本实验研究开发了新型中介电常数Y2O3-2TiO2系微波介质陶瓷,并在此基础上添加Bi2Ti2O7陶瓷粉料进行复相掺杂。利用网络分析仪,阻抗分析仪,XRD,SEM等方法,本文重点研究了不同Bi2Ti2O7掺杂量对Y2O3-2TiO2系微波介质陶瓷材料烧结性能和介电性能的影响。通过分析发现适量掺杂能够有效降低材料的烧结温度,并使材料致密化。同时由于Bi3+置换主晶相中的Y3+形成了固溶体,材料主晶相为烧绿石结构并未改变。当添加质量分数为8wt%时获得介电性能较好的陶瓷材料,烧结温度从未掺杂的1460℃降低到1320℃。在1M下:εr≈62.14,tanδ≈1.22×10-3,微波频率(4.55GHz)下εr≈62.85,Q.f=4122.8GHz,τf=-7ppm/℃。
Various permittivity dielectric material systems are examined frequently. However, middle permittivity dielectric ceramics with their εr values range from 40 to 80 are still lacking. For adapting to the development of microwave communication technology, a new system-Y2O3-TiO2 ceramic has been investigated, and then Bi2Ti2O7 ceramic powder is added to improve its＇ properties. In this paper, the relation between the doping ratio and dielectric character is investigated by impedance analyse apparatus, network analyse apparatus, X-ray diffraction apparatus（XRD） and scanning electron microscope （SEM）. It shows that the major crystal phases of pure and Bi2Ti2O7-doped Y2O3-2TiO2 ceramic are all pyrochlor. The dielectric properties depended largely on the amount of Bi2 Ti2 O7 substitution and sintering temperature. While, the sintering temperature of Y2O3-TiO2 ceramics perfect amount of substitution of Bi2Ti2O7 is effectively lowered. When the 8wt% Bi2 Ti2O7-doped Y2 O3-2TiO2_based ceramic sintered at 1320℃, the dielectric properties are better： εr≈62.14,tanδ≈1.22×10^-3（1MHz） ; εr≈62.85,Q·f=4122.8GHz,τf=-7ppm/℃.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2009年第3期455-459,共5页
Journal of Materials Science and Engineering
基金
江苏省高校自然科学研究重点资助项目(08KJA430002)
关键词
微波介质陶瓷
中介电常数
钛酸铋
氧化钇
microwave dielectric ceramics
middle permittivity
Bi2Ti2O7
yttrium oxide
