Revised phase diagram and X‐ray data of The Mn₃O₄Al₂O₃ System in air

Abstract

Abstract The phase diagram of the quasi‐binary Mn 3 O 4 Al 2 O 3 system in air has been redetermined at temperatures from 850 to 1550°C with the help of the X‐ray powder diffraction technique including high‐temperature diffractometry. Lattice constants of manganese aluminates and the powder diffraction patterns of Mn 3 O 4 , MnAl 2 O 4 and Mn 2 AlO 4 are presented. The influence of specimen cooling on the cubic‐to‐tetragonal transition of MnAl spinels is demonstrated. The inversion degree of the spinal compounds is discussed.