Mullite formation from nonstoichiometric slow hydrolyzed single phase gels

Abstract
A comparative dynamic x-ray diffraction (DXRD) and differential thermal analysis (DTA) study was performed in the investigation of mullite and spinel formation from slowly hydrolyzed single phase gels with Al/Si ratios ranging from 1/1 to 14/1. Both metastable tetragonal mullite and spinel were observed to form at temperatures 2O3 · SiO2 and 6A12O3 · SiO2, respectively.