Oxidation Resistance, Electrical and Thermal Conductivity, and Spectral Emittance of Fully Dense HfB2 and ZrB2 with SiC, TaSi2, and LaB6 Additives
Abstract
The oxidation resistances of ZrB2 containing SiC, TaB2, and TaSi2 additions of various concentrations were studied using isothermal thermogravimetry at 1200, 1400, and 1500 deg C. Theoretically-dense ZrB2-SiC two-phase microstructures were isothermally oxidized for ~90 min in a thermogravimetric analyzer in flowing air in the range 1500-1900 deg C. The oxidation resistances of theoretically-dense HfB2-SiC test specimens were evaluated via isothermal thermogravimetry at 1600, 1700 and 1800 deg C. The thermal diffusivities of theoretically dense ZrB2-SiC (10.7, 21.9, or 48.7 vol% SiC) sintered/HIPed with B4C sintering aid was measured using the laser flash technique. Spectral emittances of direct electrically-heated ZrB2-30 mol% SiC specimens were measured in the 1-6 micrometer range.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 26, 2012
- Accession Number
- ADA563908
Entities
People
- Robert F. Speyer
Organizations
- Georgia Tech