|About this Abstract
||Materials Science & Technology 2011
||MS&T'11 Poster Session
||037 Critical analysis of experimental methods for reliable oxidation rate measurements of ultra-high temperature ceramics using thermal gravimetric analysis up to 1600°C
||Melia Miller-Oana, Luke Walker, William Pinc, Erica Corral
|On-Site Speaker (Planned)
During hypersonic flight, vehicles need materials such as ultra-high temperature ceramics for thermal protection system in order to withstand temperatures greater than 2000˚C; therefore, understanding the oxidation behavior of these materials is important. We examine oxidation behavior of ZrB2-SiC composites by investigating the ratio of total specimen edge length to total specimen surface area and determine its relevance for developing reliable oxidation methods. In situ mass gains during ZrB2-SiC oxidation are measured with thermogravimetric analysis. Reproducible oxidation rates are not obtained due to varying edge length and surface area of ZrB2-SiC composites. Using identical conditions, mass gains during heating to 1400°C range from 0.93% to 0.14% for total specimen edge length to surface area ratios of 1.28 and 0.33, respectively. For reliable data, sample parts with ratios less than 0.5 should be used for oxidation testing due to the reduced effect of edge and corner oxidation compared to bulk oxidation.