TG測定によるα炭化ケイ素粉体の高温酸化反応挙動の解析

摘要

The oxidation behavior of alpha-SiC powders at elevated temperature was studied by using a TG (thermo-gravimetry) analyzer. Oxidation reactions were observed at two temperature regions. First one is due to the oxidation of free carbon around 700 deg C, and the other is caused by the oxidation of alpha-SiC particle surface around 1000 deg C. The oxidation starting temperature and the amount of oxidation product (SiO_2) depend on the size of alpha-SiC particles. It was found that the starting temperature of the oxidation decreases with the particle size. The amounts of oxidation product increase with the decrease of particle size as well. It is concluded that the oxidation rate at around 1000 deg C is constant since the values of oxidation amount per unit area is almost uniform independent of the particle size of alpha-SiC powders.