Oxidation of Boron Nitride Powder in Wet Oxygen.

Oxidation kinetics of hexagonal boron nitride powder in 8% O2-20% H2O/balance argon was investigated at 900-1100°C. Paralinear weight change curves were observed. The rate constant of BN oxidation in 8% O2-20% H2O/balance argon was almost the same as that in 20% H2O/balance argon at the temperature below 1000°C, while at higher temperatures it was almost the same as that in 10% O2/balance argon.