mica (nealed)

The sample started sticking to bowl and balls. This uses to happen after the majority of particles reached a fineness of < 20-30µm. Interacting forces between fine ground particles will become bigger as their own g-force. Therefore, particles will stick to each other and just become compressed by the used grinding balls. These clusters of particles also contain bigger particles which will not be ground any further too.

In this case, pieces up to 150µm still use to be present.

We don’t recommend a dry grinding of mica with a planetary mill in general.

Probably an undesired grinding in suspension will be capable to grind sample into the desired range.

Sample has been ground without any difficulties. Afterwards, a particle size analysis has been performed with our Laser Particle Sizer ANALYSETTE 22 compact.

Only 22,3% use to be < 20µm as desired.

Eventually fineness can be lightly improved by second and third feeding of sample.