钛酸锌镁陶瓷六方钛铁矿相热稳定性研究

通过XRD ,DTA ,光学显微技术系统研究了 (Zn1 xMgx)TiO3(x=0 1～ 0 4 ) (缩写为ZTM)陶瓷六方钛铁矿结构的热稳定性和相分解反应。实验发现 ,MgO可在宽广烧结温度范围内稳定钛铁矿六方相。但超过合适的烧结温度 ,x<0 2时 ,六方相 (Zn ,Mg)TiO3就会分解为 (Zn,Mg) 2 TiO4 和金红石 ;x >0 2时 ,六方相 (Zn,Mg)TiO3分解为 (Zn ,Mg) 2 TiO4 和 (Zn ,Mg) 2 Ti3O8。

LTCCs用低温烧结(Zn，Mg)TiO_3介电陶瓷

通过化学法结合固相烧结技术制备了(Zn,Mg)TiO_3(简称ZMT)陶瓷,掺杂V_2O_5降低陶瓷的烧结温度,研究了V_2O_5掺杂ZMT陶瓷的低温烧结行为、相转变以及介电性能。结果表明:化学法结合V_2O_5掺杂有效地将钛酸锌陶瓷烧结温度从1200～1300℃降至900℃以下;Mg的加入增强了六方相的热稳定性,扩展了六方相的稳定区间。V_2O_5掺杂ZMT陶瓷具有良好的介电性能,875℃烧结的ZMT陶瓷介电常数ε_r=22,介电损耗tanδ=5.7×10^(-4),是制备LTCCs(低温共烧陶瓷电容器)的优秀候选材料,具有很好的应用前景。

BaTiO_3陶瓷中Nb_2O_5-Zn_(0.8)Mg_(0.2)TiO_3的掺杂效应

研究了BaTiO3-Nb2O5-Zn0.8Mg0.2TiO3系统的介电性能及微观性能。SEM和XRD分析发现,在掺杂x(Nb)=1%的BaTiO3陶瓷中,Zn0.8Mg0.2TiO3的固溶度小于4%。Nb2O5和Zn0.8Mg0.2TiO3用量均为1%时,BaTiO3陶瓷为赝立方相结构,当x(Nb)>2%时,陶瓷样品(002)和(200)衍射峰相互分开,研究表明,BaTiO3陶瓷为四方相,且随着Nb用量增加,四方率增强。此外,Nb用量增加还使BaTiO3陶瓷室温介电常数降低,而同时居里点升高。当x(Nb)=2%和x(ZMT)=1%时,在空气中于1 180℃下烧成的BaTiO3陶瓷材料的主要性能指标为:298 K时介电常数2ε98 K=2 004,介电损耗tanδ=0.84%,密度ρ=1.4×1012Ω.cm,-55^+150℃,电容量温度变化率△C/C≤±15%。

DIELECTRIC PROPERTIES OF ZNTIO_3 MICROWAVE CERAMICS CONSOLIDATED WITH MGTIO_3

Stabilized ZnTiO4 was prepared by doping magnesium oxide through traditional solid state reaction. The experimental results indicate that zinc titanate crystals doped with magnesium oxide grow well and the decomposition into Zn2TiO4 and TiO2 is restrained through traditional solid state reaction, By adjusting molar ratio of MgO, better properties can be obtained The dielectric properties of the ceramics doped with 30% MgO（ molar percentage） sintered at 1060℃ are as follows：the value of quality factor is greater than 20000（6.5 GHz ）, the temperature coefficient of resonance frequency is about 2 ± 10^-6 /℃,the dielectric constant ranges from 180 to 22.Besides,it is proved that heat treatment can optimize microstructure and the value of quality factor, which increases from 23833.93 to 47584.00 after 2h of heat treatment at 1040℃.