Phase equilibria and solid solution relationships in the La2O3-TiO2-ZrO2 system

In the ternary La₂O₃-TiO₂-ZrO₂ system the subsolidus phase relations at 1350 °C were determined using X-ray diffraction, scanning electron microscopy end energy dispersive X-ray analysis. The collected results are presented in the form of a phase diagram. In the equilibrium state there are 7 ternary and 5 binary compatible subsystems. In the system TiO₂ss, ZrO₂ss, ZrTiO₄ss, La₂Zr₂O₇ss and La₂O₃ss solid solutions were confirmed and La₄Ti₉O₂ss and La₂Ti₂O₇ss solid solutions were identified. The addition of ZrO₂ does not stabilize the La_2/3TiO₃ perovskite compound, nor the addition of TiO₂ a highly temperature stable compound La_2/3ZrO₃.