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Journal of Materials Science

, Volume 30, Issue 21, pp 5389–5393 | Cite as

The possible role of the pre-exponential factor in explaining the increased reaction rates observed during the microwave synthesis of titanium carbide

  • J. G. P. Binner
  • N. A. Hassine
  • T. E. Cross
Papers

Abstract

Reaction rates observed during the microwave synthesis of titanium carbide powder via the carbothermal reduction of the oxide are more than three times faster than those observed during conventional processing at the same temperature. Although not dissimilar to other reports of “microwave effects” in the literature, this result is of interest because the microwave heating mechanism is quite different compared to work using ionic ceramics. The initial powder mix consisted of low dielectric loss titania mixed intimately with very fine carbon black powder. It is the latter phase which couples with the microwaves via a conventional ohmic dissipation mechanism. Calculations have shown that the faster diffusion rates might be explained by an increase in the Arrhenius pre-exponential factor A, with no change in the activation energy.

Keywords

Microwave Titanium Carbide Carbothermal Reduction Black Powder Carbide Powder 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman & Hall 1995

Authors and Affiliations

  • J. G. P. Binner
    • 1
  • N. A. Hassine
    • 1
  • T. E. Cross
    • 1
    • 2
  1. 1.Department of Materials Engineering and Materials DesignThe University of NottinghamNottinghamUK
  2. 2.Department of Electrical and Electronic EngineeringThe University of NottinghamNottinghamUK

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