Formation of Oxide Films on ZrB2–15 vol% SiC Composites During Oxidation: Evolution with Time and Temperature
Abstract:The evolution of convection cells features that form in oxide films on ZrB2–SiC composites are quantified by the number population, size, and distribution in oxide films on ZrB2–15 vol% SiC oxidized at temperatures between 1500° and 1600°C for various oxidation times. The number of convection cells per unit area increases after short exposure times of the oxidation at 1550°C, but then decreases slowly with increasing time. The results indicate that these convection cells are transient, they form and transport boria–silica–zirconia liquid to the surface but with increasing exposure time the increasing amount of flowing viscous SiO2-rich liquid submerges them and they become extinct.
Document Type: Research Article
Affiliations: Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48104
Publication date: June 1, 2009