Phase equilibrium relations in the systems titania-niobia and zirconia-niobia

Abstract

The systems TiOz-NbzOs and Zr02-Nb20 S were studied by means of solid-state reactions and by observation of fusion characteristics.Two binary conwounds, TiOz•N b20 s and Ti02•3Nb20 S, were found to exist in the Ti02-NbzOs system.One compound, 6Zr02• Nb20 S, was found to exist in the Zr02-Nb20 s system.This compound has been found to be essentially isostructural with Zr02• Ti02 and has orthorhombic symmetry with the following unit cell parameters when quenched from 1,550 0 C : a = 4.964 A, b= 5 .120A, c=5.289 A. Sol id-solution formation was observed in both systems.A probable equilibrium diagram is presented for each system .