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ion Fabrication and Characterization of Controlled Microstructure

Glass Composites for Electromagnetic ApplicationsRosario A. Gerhardt, Georgia Tech Research Corporation, DMR 1207323

The controlled microstructure in these composites involves combinations of an insulating glass and a conducting nanoparticle, called a filler, that is segregated to specific regions in the composite where it forms a conducting network in which electrons can move, analogous to cars moving on a highway. The formation of these composites is controlled by two methods: (1) particle size ratio where the larger glass regions segregate the nanoparticles to the gaps in-between the glass particles and (2) the hot pressing parameters: temperature, pressure and time. Composites formed using this method can obtain conducting pathways at very low amounts of filler. Since the method is based on the process conditions and not the specific materials itself, it can be applied to a wide range of composites and allow for many potential electromagnetic applications.

Conducting nanoparticles

Glass

(a) Schematic of microstructure of a glass composite showing how the conductive filler (red dots) is segregated between the glass particles (white regions), where the arrows indicate current flow. (b) Picture of a glass composite where the dark regions are glass and the white regions are where the conducting nanoparticles are located. (c) Magnified triple point region showing conducting pathways through the composite.

(a) (b) (c)