2011 Volume 52 Issue 8 Pages 1674-1678
Agglomerated coarse Al powders consisting of nanoparticles were synthesized by low energy ball milling process, and subsequently their structures were characterized in terms of agglomeration size, shape, and porosity depending on various milling time, ball size, and ball to powder weight ratio in order to optimize the process parameters. A higher milling time caused a decrease in the agglomeration size and their shape tends to become spherical while reducing the pore sizes. The agglomeration size was also reduced as the ball to powder weight ratio increased and the ball size decreased. The partial cold welding of the nanoparticles at lower milling time and fully cold welding of the nanoparticles at higher milling time were correspondingly responsible to produce larger and smaller agglomerations, respectively.