Conclusions
In the range 1200–1500°C the mechanism of oxidation of industrial heating elements containing 97–99% silicon carbide is approximately identical with, and is controlled in the same way, as the oxidation of pure silicon carbide [1, 2], in the main by oxygen diffusion through a film of SiO2.
The relationship between the oxidation of various silicon carbide heating elements and time is described ⋌ the equation q=Kτb, where b comes within the range 0.3–0.5. The relationship between the oxidation rate of the heating elements and the temperature obeys the Arrhenius equation: K=K0exp(−E/RT).
The calculated activation energy for the process for various heating elements alters from 23 to 43 kcal/mole.
The porosity of the heaters (up to values not exceeding 18%) substantially affects the oxidation capacity.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Literature cited
G. Wibke, Dtsch. Keram. Ges.,57, 219 (1960).
P. J. Jorgensen et al., J. Amer. Ceram. Soc.,49, 613 (1959).
J. G. Ewin, J. Amer. Ceram. Soc,41, No. 9, 347 (1958).
C. Z. Wagner, Phys. Chem.,32, 447 (1963).
K. Fischbeck et al., Z. Elektroch.,40, 517 (1934).
E. L. Williams, Amer. Ceram. Soc. Bull.,43, No. 4 (1964).
Author information
Authors and Affiliations
Additional information
Translated from Ogneupory, No.6, pp. 52–57, June, 1970.