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Diffusion-Controlled Processes in Microwave-Fired Oxide Ceramics

Published online by Cambridge University Press:  28 February 2011

Mark A. Janney
Affiliation:
Oak Ridge National Laboratory P.O. Box 2008 Oak Ridge, TN 37831
Hal D. Kimrey
Affiliation:
Oak Ridge National Laboratory P.O. Box 2008 Oak Ridge, TN 37831
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Abstract

Processing oxide-based ceramics using microwave heating leads to a number of unexpected results, which can only be interpreted in terms of enhanced diffusion. Enhanced sintering has been observed in alumina and zirconia. Accelerated grain growth in dense, hot-pressed alumina has been demonstrated. Increased diffusion coefficients have been observed for diffusion of oxygen in sapphire. As yet, a satisfactory theory to account for these phenomena has not been developed. This paper reviews the experimental work conducted at the Oak Ridge National Laboratory during the past four years on the processing of oxides in both 2.45 and 28 GHz microwave furnaces.

Type
Research Article
Copyright
Copyright © Materials Research Society 1991

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References

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