Particle shape, when particle size alone isn’t enough
Written by: Malvern
For many particle characterization applications, a particle size distribution provides adequate information about the sample. However, for some applications particle shape can provide more appropriate or complementary information. There are three main categories where this is relevant:
Single particles or agglomerates?
Many particle sizing methods require complete dispersion of any agglomerates in the sample in order to make an appropriate measurement. Being able to view individual images in the dispersion and analyze them in terms of their outline shape allows the user to determine whether or not agglomerates are present and the extent of agglomeration in the sample.
Regular or elongated?
Size reduction by milling can change the shape as well as the size of particles. This may have desirable or undesirable consequences for the processing behaviour and final properties of the material. By measuring shape parameters such as elongation or circularity, the overall sample form can be monitored and changes made to the process if required.
Rough or smooth?
The effectiveness of abrasive powders and powder flow can both be influenced by how rough or smooth the surfaces of the particles are. For example shape parameters that give information on the overall form as well as the outline of particles are useful in assessing if an abrasive powder has become worn, or if a powder is more or less likely to stick in a hopper.
If you’d like to find out more you can download a copy of the Automated Imaging Brochure by clicking on this link.