Abstract
Five kinds of silicon carbide ceramics were oxidized in flowing dry air at 1300°C for 360h and 1000h, and oxidation behaviour was studied by measuring the weight gain and thickness of oxide layer and of unoxidized substrate, in which the weight loss by evaporation of some species from the oxide layer during oxidation was taken into account. The change of thickness of substrate was complicated, and some samples expanded during oxidation. Therefore, no direct correlation is possible between evapolation and dimensional change of substrate. To evaluate the oxidation resistance correctly, the thickness, density and texture of the oxide layer must be examined together with the weight gain.
