Phase equilibria of Al2O3-SiO2-La2O3 system at 1873 K, 1773 K and 1673 K

Al₂O₃-SiO₂-La₂O₃ system is a typical basic RE-containing ceramic system. The phase diagram of this system is useful for the research and development of RE in ceramic materials; besides, it is also indispensable for the thermodynamic database of multicomponent RE-containing ceramic systems. In this paper, we employed high-temperature equilibrium experiments and quenching methods followed by scanning electron microscope (SEM), electron probe microanalysis (EPMA) and X-ray diffraction (XRD) to determine the morphology, composition and type of equilibrium phases in the Al₂O₃-SiO₂-La₂O₃ system, respectively. Based on the experimental results, three isothermal sections at 1873 K, 1773 K and 1673 K were clarified; the solid solubility of the compound phase at the experimental temperature were clarified.