4. Oxidation at very high temperatures

Ultra-refractory ceramics, intended for use in a variety of very high-temperature environments with varying pressure conditions (atmospheric re-entry, hypersonic velocity, solar receiver...), need to be studied under experimental conditions as close as possible to the application. In particular, conventional electric furnaces are unable to reach the operating temperatures of these materials, or to achieve high rates of temperature rise. This calls for the use of high-temperature sources such as induction furnaces, plasma torches, plasmatrons, oxyacetylene torches and solar furnaces, whether or not combined with plasma resources.

The oxidation of ceramics based on zirconium and hafnium borides and carbides has been extensively studied, as has that of their combination with SiC, the latter having been added, in powder or fiber form, to improve resistance to high-temperature...