Oxidation Resistance of Silicon-based Ceramics

摘要

Silicon-based ceramics have an excellent oxidationresistance at high temperatures due to a protective SiO2 layerwhich prevents further oxidation. At low oxygen partial pressures,on the other hand, the surface of these ceramics would be directlyattacked by an oxidant forming SiO vapor, which may significantlydegrade their mechanical or protective performance. These twokinds of distinct behavior are termed passive and active oxidation.Another characteristic oxidation feature of the silicon-basedceramics is bubble formation which probably determines thehighest temperature for usage. Therefore, it is important toinvestigated the oxidation behavior of these ceramics in a widerange of oxygen partial pressures and temperatures. In the presentpaper, the transition mechanism from the active to passiveoxidation and several issues on the passive oxidation are reviewed.