U ovom radu opisana je sinteza veoma čistih, submikronskih, sfernih čestica α-Al_2O_3 praha metodom ultrazvučnog reakcionog raspršivanja. Kao polazna jedinjenja korišceni su 0,5M vodeni rastvori AlCl_3·6H_2O i Al(NO_3)_3·9H_2O. Prikazan je uticaj geneze kapljica aerosola na raspodelu veličine čestica α-Al_2O_3· Za veoma fine kapljice aerosola ( < 3 μm ), nezavisno od vrste izabranog polaznog jedinjenja, pretipkacija rastvorenog jedinjenja unutar kapi odvija sezapreminskim mehanizmom. Morfologija čestica u celini odgovara morfologiji kapljica aerosola. Povećana aktivnost dobijenih prahova omogućuje na temperaturama između 800℃ i 900℃ faznu transformaciju γ—u α-Al_2O_3, pri čemu je već na 1000℃ proces transformacije završen u celini.%Synthesis of very pure submicrometer spherical particles of α—alumina by ultrasonic spray pyrolysis is considered. 0.5M water solutions of both AlCl_3·6H_2O and Al(NO_3)_3·9H_2O have been used as the precursors. The influence of aerosol droplet genesis on particle size distribution of α—alumina has been considered. In the case of very fine droplets (less than 0.3 μm ), independently of the precursor, the precipitation of dissolved compound inside the droplet occurs by the volume mechanism. Particles morphology is in accordance with droplets morphology. An increased activity of produced powders enables phase transformation of γ- to α-alumina in temperature range 800℃ - 900℃. At 1000℃ the transformation is completelly over.
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