Revised phase diagram and X‐ray data of the Mn\u3csub\u3e3\u3c/sub\u3eO\u3csub\u3e4-\u3c/sub\u3eAl\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e3\u3c/sub\u3e system in air

\u3cp\u3eThe phase diagram of the quasi‐binary Mn\u3csub\u3e3\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3eAl\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e3\u3c/sub\u3e 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\u3csub\u3e3\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e, MnAl\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e and Mn\u3csub\u3e2\u3c/sub\u3eAlO\u3csub\u3e4\u3c/sub\u3e are presented. The influence of specimen cooling on the cubic‐to‐tetragonal transition of MnAl spinels is demonstrated. The inversion degree of the spinal compounds is discussed.\u3c/p\u3