Some thermodynamic properties in spinel solid solutions with the Fe 3O 4 component

Abstract

Phase equilibria in FeFe 2O 3Cr 2O 3, FeFe 2O 3V 2O 3, FeOFe 2MoO 4Fe 3O 4, and FeOFe 2O 3ZrO 2 systems were precisely determined. On the basis of the present results, together with the FeOFe 2O 3TiO 2 system studied by Taylor at 1300°C and by Webster and Bright at 1200°C, the following results were obtained. (1) The solid solutions Fe 2TiO 4Fe 3O 4, and Fe 2MoO 4Fe 3O 4 are approximately ideal in respect to the activity-composition relation. (2) On the contrary, the solid solutions FeCr 2O 4Fe 3O 4 and FeV 2O 4Fe 3O 4 deviate significantly from Raoult's law, and these are of regular solution defined by Hildebrand.