Spinel solid solutions in the systems MgAl2O4-ZnAl2O4 and MgAl2O4-Mg2TiO4

Phase relations in two binary systems MgAl2O4-ZnAl2O4 and MgAl2O4-Mg2TiO4 have been studied and phase diagrams for them have been constructed. Based on the data of x-ray phase and crystal-optical analyses, the formation of a continuous series of solid solutions with spinel structure between the terminal members of the systems studied has been established. In the MgAl2O4-ZnAl2O4 system the solid solution is stable in the range from room temperature to melting temperature. In the MgAl2O4-Mg2TiO4 system the solid solution decomposes below 1380 degrees C, yielding the formation of limited regions of homogeneity on the basis of MgAl2O4 and Mg2+2 deltaTi1-deltaO4 Decomposition of the solid solution is accompanied by crystallization of MgTiO3.