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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
Solid State Division, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, TN 37831
L. S. Darken
Solid State Division, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, TN 37831
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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.

Research Article
Copyright © Materials Research Society 1984

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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.



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