激光快速凝固法制备BaTi_4O_9微波介质陶瓷  

Microwave dielectric ceramic BaTi_4O_9 synthesized by laser rapid solidification

作　　者：张俊吉[1] 李明玉[1] 李德川[1] 晁明举[1] 梁二军[1] 

机构地区：[1]郑州大学物理工程学院材料物理教育部重点实验室,河南郑州450052

出　　处：《光电子．激光》2012年第4期703-707,共5页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(51072238);河南省教育厅自然科学研究计划(2001B140022)资助项目

摘　　要：采用激光快速凝固(LRS)法,制备四钛酸钡(BT4,BaTi4O9)微波介质陶瓷,使用X射线衍射仪(XRD)、扫描电子显微镜(SEM)分析晶相构成及显微组织,使用精密阻抗分析仪测试介电性能。结果表明,LRS制备BT4呈层片状结构,具有较高的致密度(相对密度99.6%),其晶粒沿c轴方向(平行于激光入射方向)择优生长,c轴方向择优取向度为0.46。在1 MHz下,介电常数为85,介电损耗为0.083,介电常数温度系数为1.96×10-4。由于在LRS过程中熔体产生极大的温度梯度,因而形成织构化的BT4,介电常数显著提高。Microwave dielectric ceramic BaTi4O9 was synthesized by laser rapid solidifcation（LRS） with CO2 laser.As-synthesized BaTi4O9 has a higher density（relative density is 99.6%.The analysis of X-ray diffraction（XRD） reveals that the samples are of highly pure phase and the grains grow along the c-axis direction with a high lotgering factor of 0.46.The observation of scanning electron microscopy（SEM） shows that the so-synthesized ceramics are composed of plate-like microstructures parallel to the laser incident direction.The dielectric constant,dielectric loss and temperature coefficient of dielectric constant are 85,0.083 and 1.96×10-4 at 1 MHz,respectively.The strong temperature gradient in the sample′s interior generated during the solidification process results in the appearance of textured microstructure and the improvement of dielectric constant.

关 键 词：激光技术 激光快速凝固(LRS) 织构 介电性能 

分 类 号：TB321[一般工业技术—材料科学与工程]