Abstract
The kinetics of the carbothermic reduction of SiO2 by carbon to produce β-SiC from a homogeneous organic precursor has been investigated over the temperature range 1500 to 1800 °C in nitrogen by the use of a high-temperature thermobalance. The kinetic behaviour differed significantly from that of the heterogeneous reaction of SiO2 and carbon particles. The weight-loss curves could be fitted well by the Avrami-Erofe'ev equation with an exponent of 1.5. The result was interpreted as showing instantaneous nucleation in a homogeneous matrix followed by the diffusion-controlled growth of β-SiC. The obtained activation energy of 391 kJ mol−1 was consistent with the assumption that the reaction is controlled by the diffusion of carbon through the amorphous matrix to the growing surface of β-SiC.
Similar content being viewed by others
References
H. Tanaka andY. Kurachi,Ceramics Int. 14 (1988) 109.
M. S. Khrushchev,Izv. Akad. Nauk SSSR, Met. (1984) 23.
K. Schwerdtfeger,Trans. Met. Soc. AIME 236 (1966) 1152.
A. G. Vodopy'anov, S. V. Baranov andG. N. Kozhebnikov,Izv. Akad. Nauk SSSR, Met. (1983) 28.
T. Shimoo, F. Mizutaki, S. Ando andH. Kimura,J. Jpn Inst. Metals 52 (1988) 279.
Idem, ibid. 52 (1988) 945.
N. Klinger, E. L. Strauss andK. L. Komarek,J. Amer. Ceram. Soc. 49 (1966) 369.
W. E. Brown, D. Dollimore andA. K. Galway, in “Comprehensive Chemical Kinetics”, edited by C. H. Bamford and C. F. H. Tipper, Vol. 22 (Elsevier/North Holland, New York, 1980) Ch. 3.
T. L. Francis andR. L. Colbe,J. Amer. Ceram. Soc. 51 (1968) 115.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Ono, K., Kurachi, Y. Kinetic studies on β-SiC formation from homogeneous precursors. J Mater Sci 26, 388–392 (1991). https://doi.org/10.1007/BF00576531
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00576531