Transactions of the INDIAN CERAMIC SOCIETY Vol. 53 1994
Compaction Behaviour of Alumina Powders
I : Effect of Grinding, Calcination and
Incorporation of Fused Grains
P. G. PAL* AND B. N. SAMADDAR**
Pages : 85-90
DOI : 10.1080/0371750X.1994.10804646
Abstract
Very poor con~pac:tion occurs in case of technical grade
alumina powder produced by Bayers process. Ground,
washed and dried technical alumina powder yields low
green density (47% theoretical) even by isostatic pressing (2000
kg.cm-1 forming pressure) and does not follow any powder
compaction models suggested in the case of other irregular
shaped ceramic powders. Precalcination of the processed fine
powders (0.3 to 0.4 J.lm) between 1100° and 1600°C causes
reduction of the void volume present in the agglomerated powder
resulting in better densification ( -70% theoretical) obtained
at 1550 kg.cm-1 forming pressure. More than 80% theoretical
density in the green stage was possible with fused alumina
grains incorporated with processed technical alumina powder at
1550 kg.cm"1 forming pressure.
