TEM observation of oxide scale formed on TiC single crystals with different faces

Cross-sectional observation of the oxide scale formed by oxidation of TiC single crystals with (100), (110) and (111) faces at 1500 °C for 30 min in a mixed gas of Ar/O2 (PO2=0.08 kPa) was performed by transmission electron microscope (TEM). The oxide scale was composed of outer (zone 2) and inner (zone 1) subscales. TEM and selected area electron diffraction combined with X-ray energy dispersion analysis showed that the zone 2 consists of rutile and pores and the zone 1 of carbon and titanium oxide, identified as Ti3O5 in the oxide scale formed on the (110) face. Zone 1 formed on the (100) and (111) faces showed crisscross patterns, in contrast to the (110) with the wavy lamellar pattern.