|
authors |
Ferreira, NM; Kovalevsky, AV; Naumovich, EN; Yaremchenko, AA; Zakharchuk, KV; Costa, FM; Frade, JR |
|
nationality |
International |
|
journal |
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY |
|
author keywords |
Electrical conductivity; Thermal expansion; Spinel; Redox stability; Magnetite |
|
keywords |
THERMODYNAMIC PROPERTIES; CATION DISTRIBUTIONS; CRYSTAL-STRUCTURES; POINT-DEFECTS; FE-2+ IONS; OXIDES; SIMULATION; MAGNETITE; DIFFRACTION; THERMOPOWER |
|
abstract |
Magnetite-based spinels are considered as promising oxide materials to meet the requirements for ceramic consumable anodes in molten oxide pyroelectrolysis process, a breakthrough low-CO2 steel technology aimed to overcome the environmental impact of classical extractive metallurgy. The present work focuses on- the assessment of phase relationships, redox stability and electrical conductivity of Fe2.6Me0.2Mg0.2O4 (M = Ni, Cr, Al, Mn, Ti) spinel-type materials at 300-1773 K and p(O-2) from 10(-5) to 0.21 atm. The oxidation state of substituting transition metal cation, affecting the fraction of Fe2+ in spinel lattice, was found to be a key factor, which determines the electronic transport and tolerance against oxidative decomposition, while the impact of preferred coordination of additives on these properties was less pronounced. At T > 650 K thermal expansion of Fe2.6Me0.2Mg0.2O4 ceramics exhibited complex behaviour, and, in highly oxidizing conditions, resulted in significant volume changes, unfavourable for high-temperature electrochemical applications. (C) 2014 Elsevier Ltd. All rights reserved. |
|
publisher |
ELSEVIER SCI LTD |
|
issn |
0955-2219 |
|
year published |
2014 |
|
volume |
34 |
|
issue |
10 |
|
beginning page |
2339 |
|
ending page |
2350 |
|
digital object identifier (doi) |
10.1016/j.jeurceramsoc.2014.02.016 |
|
web of science category |
Materials Science, Ceramics |
|
subject category |
Materials Science |
|
unique article identifier |
WOS:000336352500022
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