一种粉末相对介电常数测试方法与装置的研究  

Study on a testing method and device for powder relative dielectric constant

作　　者：邹大军[1] 李锡文[1] 张嘉琪[1] 詹小斌[1] 封禄义[1] 

机构地区：[1]华中科技大学机械学院,武汉430074

出　　处：《仪器仪表学报》2014年第2期368-373,共6页Chinese Journal of Scientific Instrument

基　　金：国家重大科学仪器设备开发专项(2011YQ160002);中央高校基本科研业务费(HUST:2010MS090)资助项目

摘　　要：相对介电常数是粉末的重要物理特性,针对这一问题,研究了一种测量低频条件下粉末相对介电常数的方法及其实现装置。分析了以Bruggeman模型和Maxwell-Garnett模型为基础的粉末相对介电常数测量原理;在有限元分析的基础上,设计并搭建了一种测量由粉末与空气组成的二元介质混合物电容值的装置;运用所述方法及装置分别测试了3种粉末材料的相对介电常数。实验结果表明,所设计的装置能够有效避免边缘效应对测量结果的影响,具有良好的重复性,所得电容值可达到10-3pF量级,与现有文献相比,所得粉末相对介电常数最大误差小于10%,测量结果在合理范围之内。本系统结构简单,测量结果具有较高的精度,是一种获取低频条件下粉末相对介电常数的有效手段。Relative dielectric constant is an important physical property of powder. In order to study this issue, a method and its implementation device for the measurement of powder relative dielectric constant at low frequency is presented in this paper. The measurement principle of powder relative dielectric constant is analyzed according to the Bruggeman model and Maxwell-Garnett model. A device for measuring the capacitance of binary medium mixture composed by powder and air was designed and fabricated based on finite element analysis. Using the proposed method and device, the relative dielectric constants of three powder materials were tested. The experiment results indicate that the device presented in this paper can avoid the influence of edge effect on the measurement results, and has good re- peatability. The capacitance acquired can reach the order of 10- 3 pF. Compared with the results in literatures, the maximum error of the acquired relative dielectric constants is less than 10% ,which is within the reasonable range. The system, with a simple structure and high accuracy, is an effective means for measuring the relative dielectric con- stant of powder at low frequency.

关 键 词：相对介电常数 等效介电常数 粉末 电容测量 

分 类 号：TP212.1[自动化与计算机技术—检测技术与自动化装置]