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The Influence of Cation Stoichiometry on the Electrical Conductivity and High-Temperature Stability of MgO.nAl203 Spinel*

Published online by Cambridge University Press:  21 February 2011

E. Sonder  and
L. S. Darken
E. Sonder
Affiliation:
Solid State Division, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, TN 37831
L. S. Darken
Affiliation:
Solid State Division, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, TN 37831
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Abstract

The electrical conductivity of MgO:nAl2O3spinel has been measured for 1 < n < 3.6 for temperatures between 500 and 1400°C. The results for nonstoichiometric spinel are significantly different from those of stoichiometric material. Spinel with n up to 2 was found to be stable at temperatures above 1000°C, whereas, MgO:3.6Al2O3 exhibited multiple indications of instability and disproportionation.

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Footnotes

**

Present address: Tennelec, Inc.Oak RidgeTN 37830.

*

Research sponsored by the Division of Materials Sciences, U.S. Department of Energy under contract W-7405-eng-26 with Union Carbide Corporation.

References

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