Thermal Behavior of Perovskite-Like Phases in the GdAlO3–SrO System

The results of a study of the GdAlO 3 –SrO section, which is one of the internal sections of the Gd 2 O 3 –SrO–Al 2 O 3 ternary system, are presented. In the GdAlO 3 –SrO section three triple compounds, Gd 2 SrAl 2 O 7 , GdSrAlO 4 , and GdSr 2 AlO 5 , crystallizing in the tetragonal system, are synthesized. The data on the mechanism of their solid-phase formation are systematized. The results of the thermal stability of perovskite-like phases in the GdAlO 3 –SrO system are presented in a wide temperature range of 1100–1800°C in air. The congruent character of the melting of Gd 2 SrAl 2 O 7 , GdSrAlO 4 , and GdSr 2 AlO 5 complex oxides is established and their melting temperatures are determined.