Abstract
The cluster variation method, in the single prism approximation, is used to model phase relations in the system, Fe2O3-FeTiO3. Ordering in FeTiO3 is analyzed, and it is shown that the stabilization of FeTiO3 (relative to mechanical mixing of Fe2O3 and Ti2O3) includes: (1) a contribution from the redox reaction, Fe3++Ti3+→Fe2++Ti4+ (ΔH redox∼−70kJ mole−1); and (2) a contribution from ordering (ΔH OD∼−8kJ mole−1). A theoretical phase diagram is presented and compared with available experimental data. Semiquantitative agreement between theory and experiment (on the location of phase boundaries) is achieved; but, owing to the paucity of experimental data on coexisting phases, these results may be fortuitous.
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Burton, B. Thermodynamic analysis of the system Fe2O3-FeTiO3 . Phys Chem Minerals 11, 132–139 (1984). https://doi.org/10.1007/BF00309251
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DOI: https://doi.org/10.1007/BF00309251