Effect of oxygen partial pressure on the high-temperature oxidation of CVD SiC

Abstract The oxidation behavior of chemically vapor-deposited silicon carbide (CVD SiC) was studied at 1670–2010 K in O2–Ar and CO2–Ar. The oxidation kinetics in O2–Ar was parabolic or linear parabolic, and was parabolic in CO2–Ar. The activation energy for the parabolic rate constants (kp) was 210–220 kJ/mol in O2–Ar, and was 290–300 kJ/mol in CO2–Ar. The oxygen partial pressure (PO2) dependence of kp was expressed as kp∝ (PO2)n, where n=0.08–0.13 and 0.37–0.53 in O2–Ar and CO2–Ar, respectively. Bubbles were formed at more than 1985 K and PO2>5 kPa. The bubble formation temperature decreased with decreasing PO2 at PO2