摘要
以新型的具有中介电常数的Y2Ti2O7系微波介质陶瓷为研究基体,选用PbTiO3为改性添加剂,采用X射线衍射仪、扫描电子显微镜、网络分析仪和阻抗分析仪等现代测试仪器对材料的性能进行了表征,重点研究了PbTiO3掺杂后陶瓷材料的物相组成和介电性能。结果表明:PbTiO3掺杂没有改变材料的主晶相,仍为A2B2O7型烧绿石结构,由此推测PbTiO3可能固溶到Y2Ti2O7陶瓷晶格中。Pb2+占据Y3+所在的A位,且同时产生新的空位缺陷,破坏了材料的有序度,提高了晶格扩散速率,有效降低了陶瓷的烧结温度。少量Pb元素的加入使材料的晶胞常数增大,单位晶胞体积变大,Ti4+具有更大的运动空间,提高了材料本身的离子总极化率,从而提高材料的介电性能,尤其是介电常数值。当PbTiO3掺杂量为2%时,在1345℃下烧结,介电性能较好:εr=56.4,tanδ=1.21×10-3,Q×f=4776 GHz。
A new kind of Y2Ti2O7 microwave dielectric ceramics with middle dielectric constant was studied with an addition of lead titanate.The properties were characterized and measured by X-ray diffraction,scanning electron microscopy,network analyzer and impedance analyzer.The phase composition and dielectric properties of ceramics doped with PbTiO3 were investigated.The results showed that the main phase of PbTiO3 doped ceramics did not change and still exhibited a kind of pyrochlore structure.It could be specula...
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2010年第6期875-879,共5页
Chinese Journal of Rare Metals
基金
江苏省高校自然科学重点项目(08KJA430002)资助
关键词
微波介质陶瓷
钛酸铅
烧绿石结构
掺杂
microwave dielectric ceramics
lead titanate
pyrochlore structure
doping
