Effect of addition of alumina sol on γ→α phase transformation of ultrafined alumina

The effect of alumina Sol on the a phase transformation in gamma-alumina powder has been studied. In comparison with alpha-alumina seeds, the alumina Sol can also act as seeds. Moreover, because of the small particle size and perfect dispersibility of the alumina sol, the alpha phase transformation temperature is decreased and, meanwhile, the microstructure of the produced powders is modified. So ultrafined powders with a particle size less than 100 nm were produced with good dispersibility. The alpha phase transformation of the alumina precursors with alumina sol doping was studied on the base of the TEM photographs of the produced powders.