Subsolidus phase relations in the La₂O_3–Fe₂O_3–Al₂O₃ system

The subsolidus phase relations in the La–Fe–Al–O system were investigated for solid oxide fuel cell (SOFC) applications. Five compounds, LaAlO₃, LaAl₁₁O₁₈, LaFe₁₂O₁₉, AlFeO₃, and LaFeO₃, coexist in the La–Fe–Al–O system at 1380 °C in air. The microstructure and composition of the samples were studied by x-ray diffractometry and scanning electron microscopy. Based on experimental evidence, a phase diagram of the La₂O₃–Al₂O₃–Fe₂O₃ system has been proposed.