Reactive Processing and Co-Extrusion of Ultra-High Temperature Ceramics and Composites
Abstract
The processing, properties, and performance of zirconium diboride-ceramics were studied. The initial phase of the work focused on improving the properties of zirconium diboride silicon carbide ceramics prepared from commercial powders by minimizing the-impurity content and controlling the grain size of ceramics prepared by conventional hot pressing. Strengths of more than 1000 MPa (1 GPa) were measured for zirconium diboride containing 20 or-30 volume percent silicon carbide, much higher than previous reports. Another aspect of the work focused on controlling the meso-scale architecture of zirconium diboride based ceramics using co-extrusion processing. The resulting fibrous monolithic-ceramics demonstrated non-catastrophic failure behavior. As part of this research, a pressureless sintering process was developed whereby zirconium diboride could be sintered to near theoretical density without applied pressure or liquid phase sintering aids. Development of the sintering process continues under follow-on funding through the Air Force Research Laboratory. The oxidation behavior of zirconium diboride ceramics was-examined in static oxidation testing and arc jet testing. Finally, reactive processes were developed to produce zirconium diboride and zirconium diboride-silicon carbide ceramics.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 28, 2006
- Accession Number
- ADA444682
Entities
People
- Adam L. Chamberlain
- Gregory E. Himas
- James W. Zimmerman
- William G. Fahrenholtz