After 1 minute of dry grinding of sample Si-Mn, fine particles started to stick stronger, mainly to the used grinding balls.
This usually happens after the majority of particles reached a fineness of < 20-30 ìm. Interacting forces between fine ground particles will become bigger as their own g-force.
Therefore, particles will stick to each other and become compressed by the used grinding balls. These clusters of particles also contain bigger particles which will not be ground any further.
We took a small sample and packed separately for demonstration and proceeded grinding with isopropyl alcohol for a further minute to mobilize the sticking particles again.
When particles started sticking, also a grinding in suspension
is suitable to achieve a better grinding result.
Ground sample has been packed into a plastic bottle after a
total grinding time of 2 minutes.