Production of fine aluminum powders by gas bubbling atomization process

A new type atomization technique for aluminum powders is proposed. In this process, the bubbles produced by the ejection of Ar gas into molten metal atomize it to fine liquid particles, which reach upper rotating disk cooled with liquid N2, and are crushed into the finer solid particles. The obtained aluminum powders were polycrystalline, and their shapes were very irregular. The size of particles was distributed at value between 0.5 and 10 μm. A mean particle size of the powder decreased with lowering atomization temperature and with increasing discharge of Ar gas and rotational speed of the disk. Nozzle diameter also influenced delicately on the distribution of particle size.