Advanced Powder Technology, Vol.20, No.6, 542-547, 2009
Effects of multicomponent catalyzer on preparation of ultrafine alpha-Al2O3 at low sintering temperature
alpha-Al2O3 powder, with a purity of 99.95% and an average particle size of 80 nm, was prepared via the thermal decomposition of AACH precursor. During the AACH preparation, OP-10 (alkylphenol ethoxylates) was used as a dispersant and a cleflocculating agent, and a self-confected multicomponent catalyzer (MC) was used to prevent powder agglomeration. Our experiments illustrated that: apart from the necking and agglomeration-preventing effect during the sintering process, MC had potential promotive effects on the reduction of alpha-Al2O3 phase transformation temperature by maintaining the powder particles in a comparatively dynamic-sintering state, thus significantly improving the dispersibility of the sintered powder. BET and ICP analyses indicated that MC was propitious for increasing the specific surface area of the formed alpha-Al2O3 powder and induced very tiny impurities in the sintered products. (C) 2009 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.