THE STABILIZATION OF ZIRCONIUM DIOXIDE IN THE TERNARY-SYSTEM CAO-TIO2ZRO2

The subsolidus diagram of the ternary system CaO-TiO2-ZrO2 has been de termined, then used for the study of the stabilization of zirconium di oxide. It has been found that only three of the eight elementary terna ry subsystems are suitable for stabilization. ZrO2-CaO.ZrO2-CaO.TiO2, ZrO2-CaO.TiO2-CaO.ZrO2.2TiO(2) and ZrO2-ZrO2.TiO2-CaO.ZrO2.2TiO(2). Th e phase composition at thermodynamic equilibrium has been determined f or twelve compositions in these three subsystems. The phases have been determined by X-ray diffraction on samples fired at temperatures in t he range 1350-1450 degrees C. It has been found that, for full stabili zation of zirconium dioxide, at temperatures under 1450 degrees C, if is necessary to choose compositions in the elementary ternary subsyste m ZrO2-CaO.ZrO2-CaO.TiO2. The cubic variety of the resulting zirconium dioxide is characterized by a = 5.10 Angstrom. (C) 1997 Elsevier Scie nce Limited.