|About this Abstract
|Materials Science & Technology 2020
|Ceramic and Crystal Materials for Optics and Photonics
|Manipulating Properties via Grain Size Engineering in Transparent Ceramics
|James A. Wollmershauser, Boris N Feigelson, Lukasz Kuna, John Mangeri, Kevin P Anderson, Heonjune Ryou, Eric A Patterson, Edward P Gorzkowski, Serge Nakhmanson
|On-Site Speaker (Planned)
|James A. Wollmershauser
Mechanical property improvements achieved in ceramics by reducing the grain size of bulk dense polycrystalline components is a well-known phenomenon called the Hall-Petch relationship. Recent advances in ceramic sintering processing has allowed the opportunity to explore the limits of those property improvements and re-evaluate other grain size dependent phenomena, such as optical transmission, thermal conductivity, and dielectric properties. In some cases, properties improvements can be extreme, but only evident at the nanoscale – grain sizes below ~100 nm. In other cases, property changes can be minimal supporting that the underlying mechanisms are grain size agnostic. Interestingly, modeling of overlapping phenomena in some special cases, such as piezoelectric optical ceramics, indicate the possibility to modulate properties with an externally applied stimulus. This talk will cover recent work in the literature, at NRL, and with NRL collaborators on grain size dependent properties relevant to optical ceramics.