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Article dans une revue
Effect of humidity on the dielectric constant and electrical impedance of mesoporous zirconia ceramics
Abstract : The effect of humidity on the dielectric constant and electrical impedance of porous 8 mol% yttria stabilized zirconia ceramic is examined. Samples with pore volume fractions from 33% to 55% were prepared from a fine powder by uniaxial pressing and firing. Measurements, in different relative humidities from <3% to 100%, showed a strong increase of dielectric constant with water content of the unfired and fired porous ceramics. The dielectric constant can be described with good agreement to experimental values using a 2 step model involving the Hashin-Shtrikman upper bound and Landauer’s effective medium relation, analogous to the behavior of thermal conductivity. Water is assumed to be located as a layer of variable thickness on the interior solid surfaces of the pores. A.c. impedance measurements also reveal a short circuit of insulating dielectric behavior at higher water contents, interpreted as surface conduction of protons.
https://hal-unilim.archives-ouvertes.fr/hal-01875310
Contributeur : Beatrice Derory <>
Soumis le : lundi 17 septembre 2018 - 11:09:47
Dernière modification le : vendredi 28 février 2020 - 13:26:14
Contributeur : Beatrice Derory <>
Soumis le : lundi 17 septembre 2018 - 11:09:47
Dernière modification le : vendredi 28 février 2020 - 13:26:14
