Graphite

A bit of alcohol has been given to the slurry additionally for helping moisten the sample. Amount of water has been chosen to prepare motor oil like viscosity for best grinding results.

To avoid overpressure, we ground the sample in steps of 3 minutes, followed by a programmed pausing time of 10 minutes. After several cycles, the outside temperature of the bowl should be checked (remain below 80°C); grinding time or programmed pausing time might be readjusted afterwards.

Graphite itself uses to have lubricant properties. For this, a grinding of pure graphite is very tricky. Best grinding result has been achieved after a total grinding time of 60 minutes. Still ~ 15% use to be bigger as desired (> 6µm); see measure number 3323 on separate page.

After a grinding time of 2 hours, already 99,9% of particles might be < 6µm (see meas. no. 3331 on separate page). But d50 < 3,3µm has become bigger, compared to the 60 minute grinding result.

By longer grinding time, following results became worst (probably layers of graphite became compressed together / layers became flatten out and got wider). Probably 20-30 minutes of grinding might show a better ratio of particles < 6µm.