AL2TIO5 PREPARATION STARTING WITH REACTIVE POWDERS OBTAINED BY SOL-GEL METHOD

Individual Al2O3, TiO2 and SiO2, as well as binary Al2O3-TiO2 powders have been obtained by sol-gel method, polymeric route. The obtained po wders have been characterized by X-ray diffraction (XRD), IR-spectrome try, and transmission electron microscopy (TEM) methods. In the used e xperimental conditions amorphous, submicronic, monodisperse powders ha ve been obtained. The preparation of Al2TiO5 arm of some compositions situated in the Al2TiO5 Al6Si2O13 pseudobinary system has been realize d by solid-state reaction starting with the mentioned above powders. T he thermal treatment schedule of the pressed powder mixtures has been established according to the results of differential thermal and therm ogravimetric analysis (DTA/TGA). The formation of the compound has bee n followed bq XRD, dimensional variation of the samples and apparent d ensity measurements. The results obtained starting with reactive powde rs have been compared with those obtained starting with commercial pow ders. The samples hare shown a high reactivity and the formation of ti alite was enhanced. However the sintering tendency was not essentially increased. (C) 1998 Elsevier Science Limited All rights reserved.