摘要
采用溶胶-凝胶法制备出包裹MgO粉体的BST凝胶,凝胶经干燥、预烧后得到BST/MgO粉体。DTA/TGA、XRD和EDs分析以及sEM和TEM观察表明,BST在650℃晶化基本完成,1300℃烧结体的晶粒均匀,气孔呈圆形。确定出BST凝胶预烧温度为700℃,BST/MgO陶瓷的烧结温度为1300℃。在1300℃烧结后,等静压试样的相对密度达到92.4%,径向收缩率为18.1%,轴向收缩率为18.4%。BST/MgO陶瓷中只包含BST和MgO两相。介电性能检测表明,在8~12GHz范围内介电常数降至50以下,损耗角正切达10-2数量级。
The BST gel enwrapping MgO powder has been prepared hy Sol-Gel method, and BST/MgO compos- ite powder has been obtained after drying and presintering. The analysis of DTA/TGA, XRD and EDS and the observation of SEM and TEM show that the crystallization of BST finished at 650℃ and the crystal grain of sample sintered at 1 300 C is homogeneous and the pore is circular. The presintering temperature of BST gel and the sinte- ring temperature of BST/MgO ceramic are determined to 700℃ and 1 300℃, respectively. The relative density, the radial shrinkage rate and the axial shrinkage rate of the isostatic pressing sample sintered at 1 300 ℃ are 92.4%, 18. 1 % and 18.4%, respectively. And BST phase and MgO phase are found in BST/MgO ceramics. Dielectric prop- erty tests show that the dielectric constant is less than 50 and the loss tangent is about 10^-2 scale in the frequency region from 8 GHz to 12 GHz.
出处
《压电与声光》
CSCD
北大核心
2009年第1期80-83,共4页
Piezoelectrics & Acoustooptics