Phase equilibria in the system V 2O 3Ti 2O 3TiO 2 at 1473°K
Abstract
The phase equilibria in the V 2O 3Ti 2O 3TiO 2 system have been determined at 1473°K by the quench method, using both sealed tubes and controlled gaseous buffers. For the latter, {CO2}/{H2} mixtures were used to vary the oxygen fugacity between 10 -10.50 and 10 -16.73 atm. Under these conditions the equilibrium phases are: a sesquioxide solid solution between V 2O 3 and Ti 2O 3 with complete solid solubility and an upper stoichiometry limit of (V, Ti) 2O 3.02; an M 3O 5 series which has the V 3O 5 type structure between V 2TiO 5 and V 0.69Ti 2.31O 5 and the monoclinic pseudobrookite structure between V 0.42Ti 2.58O 5 and Ti 3O 5; series of Magneli phases, V 2Ti n-2 O 2 n-1 Ti nO 2 n-1 , n = 4-8; and reduced rutile phases (V, Ti)O 2- x, where the lower limit for x is a function of the {V}/{(V + Ti)} ratio. The extent of the different solid solution areas and the location of the oxygen isobars have been determined.
- Publication:
-
Journal of Solid State Chemistry France
- Pub Date:
- January 1977
- DOI:
- 10.1016/0022-4596(77)90048-2
- Bibcode:
- 1977JSSCh..20...29B