Influence of nanocrystalline grain size on the breakdown strength of ceramic dielectrics

Abstract

In an effort to develop transmission lines with higher energy storage capabilities for compact pulsed power applications, the University of Missouri-Rolla (UMR) and the University of New Mexico (UNM) have undertaken a collaborative approach to developing and studying ceramic dielectrics. At UMR, the electrical breakdown strength (BDS) of TiO/sub 2/-based materials is investigated for high energy density applications. The results of research to-date show that dense titania ceramics with nanocrystalline grain size (/spl sim/200 nm) exhibit significantly higher BDS as compared to ceramics made using coarse grain materials. Processing-microstructure-property relationships in TiO/sub 2/ systems are found to play a role with respect to increasing the BDS. At UNM, a pulsed power system is being assembled to perform BDS studies of the ceramic materials produced at UMR. Electromagnetic simulations in support of this work will also presented. The long-term aim of this research is to enable the fabrication of large sizes of high energy density ceramics for use in pulsed power systems.