高体击穿强度线性介质陶瓷的制备及物性研究

项目名称： 高体击穿强度线性介质陶瓷的制备及物性研究

项目编号： No.U1530156

项目类型： 联合基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 陈莹

作者单位： 中国科学院上海硅酸盐研究所

项目金额： 63万元

中文摘要： 脉冲形成线是脉冲功率系统中极其重要的部件，固态介质线性脉冲形成线是实现新型高梯度脉冲加速器紧凑型、小型化和低成本维护的关键技术。目前集中研究的BaSrTiO3基介质陶瓷和玻璃陶瓷存在击穿强度低、稳定性差等不足。本项目紧密结合应用需求，设计了一种具有高击穿强度和低介电常数的介质陶瓷新体系CaO-TiO2-Al2O3，在前期工作基础上，添加SiO2和MgO等氧化物进行组成优化设计，采用溶胶凝胶法和液相包裹法相结合，制备双层“核-壳”结构纳米粉体，调节粉体制备和烧结工艺，实现介质陶瓷显微结构的精细调控，提高材料的击穿强度，降低介电常数。研究新型介质陶瓷的组成和微结构对其击穿强度和介电性能的影响规律，阐明高压脉冲电场下介质陶瓷的电击穿及其脉冲寿命的物理机制，解决制备薄长片型介质陶瓷脉冲形成线的关键技术，研制出一种高体击穿强度的低介线性固态脉冲形成线，满足我国新型高梯度脉冲加速器的需求。

中文关键词： 固态脉冲形成线；击穿强度；CaO-TiO2-Al2O3；介质陶瓷；溶胶凝胶法

英文摘要： Pulse forming line is an extremely important component in pulse power system. Linear pulse-forming line is the key technology to realize the novel high gradient compact pulse accelerator and low maintenance cost. BaSrTiO3 based dielectric ceramic and glass ceramic have been investigated as potential candidates. However, their low breakdown strength and poor stability restrains their application. Therefore, in this project, we designed a new composite ceramic CaO-TiO2-Al2O3 with high breakdown strength and low dielectric constant. Based on our previous work, SiO2 and MgO will be added to optimize the properties of CaO-TiO2-Al2O3 dielectric ceramic. The nanopowders with double nuclear - shell structure will be prepared by sol gel method and liquid phase coating process. Fine controlled microstructure of dielectric ceramic will be obtained by adjusting the powder preparation and sintering process to improve the breakdown strength and reduce the dielectric constant of the materials. The influence of compositions and microstructures of the dielectric ceramic on the breakdown strength and dielectric properties will be investigated. The mechanism of the dielectric breakdown and pulse of life under high-voltage pulsed electric fields will be clarified; the key technique on the preparation of thin and long dielectric ceramic will be solved to developed low linear solid-state pulse forming line with high breakdown strength and to meet the requirement on novel high gradient pulse accelerator.

英文关键词： Solid state pulse forming lines;Breakdown strength;CaO-TiO2-Al2O3;Dielectric ceramics;Sol - gel method