Nanograin Ceramic Optical Composite Window
Abstract
The principle objective of the Phase I STTR program was to demonstrate the feasibility of producing a dense, transparent nanocomposite material with final grain sizes less than 50 nm. The alumina/zirconia system was initially selected because it has been shown for larger scale systems that immiscible phases are particularly effective in suppressing grain growth. The work was conducted by MetaMateria Partners (MMP) in collaboration with the Particulate Materials Center (PMC) at Penn State University. Key accomplishments done in Phase I were: * Dense Al2O3-ZrO2 composites with a microstructure under 50 nm were made on a repeatable basis by densifying Al2O3-ZrO2 nanoparticulates with pressure-assisted sintering (sinter forging). Primary starting particle size was 3-5 nm (surface area 200-500 m squared/g). * Al2O3-ZrO2 nanoparticulate powders were prepared by two different methods: sonochemical processing at MMP and glycothermal processing at PMC. The sonochemical process gave finer particle sizes. * Full densification was accomplished using sinter-forging followed by hot isostatic pressing (HIP) at 12500 degrees C for 2 hours and 20,000 psi. * Limited IR transmission measurements yielded in one sample ^50% transmission.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 15, 2005
- Accession Number
- ADA437199