In situ observations of the pest oxidation process of NbSi2 at 1023Â K

Oxidation processes of poly and single crystalline NbSi2 were observed in situ by high temperature optical microscopy to clarify the pest phenomenon. Pest disintegration is mainly determined by the pre-existing cracks in the microstructure. Porosity and grain boundary are the preferential oxidation sites. Pest oxidation of NbSi2 at 1023 K is not an intrinsic material property.