GHANIZADEH, S. ... et al., 2017. Spray freeze granulation of submicrometre alpha-alumina using ultrasonication. Journal of Ceramics Science and Technology, 7(4), pp. 455-462.
Granulation is a key factor towards improvement of the flowability of fine ceramic powders to make them suitable
for industrial dry pressing. Controlled granulation of fine alumina particles with a primary particle size of ∼ 150 nm was carried out using spray-freeze drying, which led to the production of flowable granules with high crushability. The fracture surface of uniaxially die-pressed green bodies made from granules with density values of ≥ 50%of theoretical showed a uniform microstructure. Sintering experiments were performed using conventional single- and two-stage
radiant heating methods followed by density and grain size measurement and characterisation of the final dense compacts to study the efficiency of two-stage sintering in grain growth elimination. The results have been compared with those of alumina bodies prepared using similar suspension by the slip-casting route.
This paper is made available online with kind permission of the publisher.
This study was funded by the Engineering and Physical Sciences Research Council (EPSRC), United Kingdom