A kinetic study of the phase transformations in AI2O3 and Na2O . 6A12O3 by a combined use of 27A1 MAS NMR spectroscopy and x-ray diffraction : Importance of nucleation

Abstract

Phase transformations of Al2O3 and Na2O · 6Al2O3 prepared by the gel route have been investigated for the first time by 27Al MAS NMR spectroscopy in combination with x-ray diffraction. Of particular interest in the study is the kinetics of the γ → α and γ → β transformations, respectively, in these two systems. Analysis of the kinetic data shows the important role of nucleation in both these transformations.