Abstract:
The nanosized alumina powders were synthesized by aluminum nitrate and ammonium bicarbonate as raw materials in ultrasonic field.The effects of reactant concentration,disperser amounts,calcination time on alumina size were investigated systematically.The morphology and size of powders were characterized by SPM400 scanning probe micrographs.At 900 ℃,the size of alumina powders,as-prepared,was about 50 nm,when the concentration of aluminum nitrate and ammonium bicarbonate was 0.1 mol/L and 0.8 mol/L respectively,the percentage of PEG6000 was about 7%,calcinations time was around 1.25 h.And its morphology was similar to that of a ball.But too high ultrasonic frequency made against obtaining nanosized alumina powders.