Electrical Properties of Insulator-Conductor Composites

该项目的主要目的是研究绝缘体-导体复合材料的电性能，使用介电和阻抗谱作为主要的实验工具，有限元建模作为主要的计算机模拟工具。一系列具有不同体积分数的炭黑-聚合物复合材料将被制造和测试。一旦确定了渗透阈值，将制备大量具有临界体积分数的炭黑样品并进行测试。介质函数（介电常数、阻抗、电模量和导纳）的多平面分析也将完成，并为所有测试样品建模。将对所有测量样品的微观结构进行评估，并对电学数据和微观结构参数（如尺寸、分布、连通性）进行定量关联。微观结构结果将用作有限元建模的输入，以进一步完善解释。预计该项目将有助于确定渗透参数的意义，因为它们与材料的实际微观结构有关。该项目将在这一主题方面培养最多3名研究生。导体-绝缘子混合物中的渗透是本项目的主题。电话线路在网络中的分布有助于解释渗透现象。基本的概念是，如果所有必要的连接都建立起来，在温哥华拨打的电话将立即到达亚特兰大。如果有任何连接断开或不可用，则通话无法完成，期望的通信中断。这个概念可以应用于各种领域的许多其他问题。在这个项目中，渗透将通过评估绝缘和导电颗粒混合物的电导率来研究。尽管渗流已经被研究了很多年，但大多数以前的工作只考虑了直流电的行为。该项目的主要目的是评估频率（交流电）对渗透行为的影响。实验测量和理想的绝缘体-导体混合物的计算机模拟将被使用。这个项目将在这个课题上培养最多3名研究生

The main objective of this project is to investigate the electrical properties of insulator-conductor composites using dielectric and impedance spectroscopy as the primary experimental tool and finite element modeling as the primary computer simulation tool. A series of carbon black-polymer composites with varying volume fractions will be fabricated and tested. Once the percolation thresholds have been identified, a large number of samples with the critical volume fraction of carbon black will be prepared and tested. Multiplane analysis of the dielectric functions (permittivitty, impedance, electric modulus and admittance) will also be done and modeled for all samples tested. The microstructure of all measured samples will be evaluated and quantitative correlations between the electrical data and the microstructural parameters will be made (e.g. size, distribution, connectivity). The microstructural results will be used as input for the finite element modeling to further refine the interpretation. It is expected that this project will help determine the significance of the percolation parameters as they relate to the actual microstructure of materials. This project will train up to 3 graduate students in this subject matter.%%%Percolation in conductor-insulator mixtures is the subject of this project. Distribution of telephone lines in a network helps explain percolation. The basic concept is that if all the necessary connections are made, a phone call placed in Vancouver will reach Atlanta instantaneously. If any connections are broken or are inoperative, the phone call does not complete and the desired communication is broken. This concept can be applied to many other problems in a variety of fields. In this project, percolation will be studied by evaluating the electrical conductivity of mixtures of insulating and conducting particles. Even though percolation has been studied for many years, most previous work has only considered direct current behavior. The main objective of this project is to evaluate the effect of frequency (alternating current) on the percolation behavior. Both experimental measurements and computer simulations of idealized insulator-conductor mixtures will be used. This project will train up to 3 graduate students in this subject matter.***