镁掺杂对偏钛酸锌微波介电性能的影响

利用溶胶凝胶方法制备了六方密堆积结构（Zn1-xMgx）TiO3（x=0．1～0．4）固溶体．采用阿基米德排水法和微波频率下Hakki—Paoli法测定了不同Mg^2＋添加量在不同烧结温度下的陶瓷体积密度和微波介电性能．利用扫描电子显微镜（SEM）表征了不同Mg^2＋掺杂量体系在1100℃下烧结后陶瓷的形貌．结果表明，Mg^2＋掺杂能有效稳定六方密堆积结构，避免其分解为反尖晶石结构的Zn2TiO4和金红石（TiO2）．当Mg^2＋掺杂量x=0．3，1100％下烧结时，可获得最稳定、致密的六方密堆积结构陶瓷体，且该陶瓷具有优良的微波介电性能：微波介电常数（εr）=27．1、品质因数（Q＊f）=59000GHz、谐振频率温度系数（τf）=-65ppm／℃．

Microwave Dielectric Properties of ZnTiO_3 System with Mg Additive

Hexagonal close packed （hcp） （ Zn 1-xMgx ） TiO3 （ x = 0.1 - 0.4） alloy ceramics were prepared by sol-gel method. By applying Archimedes＇ principle （ displacement of water） and Hakki-Paoli method in the range of microwaves, the relative volume density and microwave dielectric properties of the system were measured. Scanning electron microscope was used to characterize the micro morphology of the ceramics sintered at 1 100℃ with different amount of Mg^2＋ addations. The additive of Mg^2＋ to ZnTiO3 system stabilizes the favored hcp structure and avoids the decomposition to inversed spinel cubic crystalline structure Zn2TiO4 and futile TiO2 effectively. When x =0.3 and sintered under 1 100℃ ,the （Zn 1-xMgx） TiO3 system shows stable dense hcp structure and good microwave dielectric properties as follows ： dielectric constant （ ε ） = 27.1,quality factor （ Q ＊f ） = 59 000 GHz, and resonance frequency temperature coefficient （ τf ） = - 65 ppm/℃.