Particle profile area and เส้นรอบรูป can be conveniently evaluated using image analysis.
However, they are varying with orientations. Therefore parameters such as the Form Factor also vary with orientations.
In addition to using the profile area and perimeter to define the form factor and roundness factor, it was found that the areas of profiles at the most stable position of particles and the sieve sizes had a non-linear correlation as shown in Figure 4, which used five sieve sizes (No.8, No.16, No.30, No.50 and No.100).
Figure 4 presents one of the nine sets of data in [17].
The remaining eight sets of data have similar correlation.
This correlation will certainly be useful in automated gradation determination as well.