Transactions of the INDIAN CERAMIC SOCIETY Vol. 54 1995
Morphological Study of Alumina Powder
Derived from Modified Precursor
AsHoK MENON AND N. B. LAXMESHWAR, MANOJ M. HARIDAS, NITIN GoYAL AND JAYESH BEU.ARE
Pages : 217-220
DOI : 10.1080/0371750X.1995.10804723
Abstract
Aluminium isopropoxide precursor has been modified by
addition of ethyl acetoacetate and subsequently hydrolysed
with excess of water to give alumina gels. These gels were
calcined at different temperatures to give different phases of
alumina powders. The surface area and porosity of the gels
were determined with and without chelating agent. The particle
size distribution of the sols was studied with respect to
variations in the amount of the chelating agent. It is found
that the above variations do bring about a change in the
morphology and the microstructure of these gel powders. In
addition to the chelating agent, 2 wt% of fine r- and a mixture
of y- and a-Al20 3 powders was added to the hydrolysed
sols. These powders acted as seeds for the promotion of-aAl203
formation. These systems were gelled, dried and heat
treated to give a-Al20 3• The morphology and the microstructure
of these seeded gels were studied and compared
with those of the unseeded gels.
