CHARACTERIZATION OF ZIRCONIA-TITANIA POWDERS PREPARED BY COPRECIPITATION

High surface area ZrO2-TiO2 powders in the entire compositional range have been prepared by a coprecipitation method. The sample with 1:1 Zr O2.TiO2 molar ratio is amorphous until crystallisation of ZrTiO4, occu rring at 970 K in DTA experiments. The presence of ZrO2 hinders the an atase crystallisation and its transformation into rutile, while the pr esence of TiO2 hinders the crystallisation of zirconia but favours mon oclinic with respect to tetragonal zirconia. Solubilities of TiO2 into the monoclinic ZrO2 phase and into the ZrTiO4 phase, as well as of Zr O2 into the rutile phase have been found. (C) 1998 Elsevier Science Li mited. All rights reserved.