The packing of particles is important in the processing of the powders
and in the ultimate properties of articles processed from the powders
. Using an apparatus originally designed for the experimental determin
ation of the packing density of powders, segregation effects with sphe
rical and nonspherical particles with low aspect ratios were studied.
The segregation of the powder samples according to particle sizes occu
rred upon vibration of the bed, following the well-known mechanisms of
segregation according to size and elutriation segregation due to entr
ainment of particles in air. Segregation effects were also demonstrate
d with a melamine powder which consisted of nonspherical particles wit
h low aspect ratios. Furthermore, additional data are provided for the
packing density values of spherical particles with multimodal particl
e size distributions, which further support the theory of Ouchiyama an
d Tanaka on the packing of spherical particles, when segregation effec
ts are not significant.