Grinding application cases — materials and results
Below are concrete grinding cases — from plant and food samples, through pigments and phosphors, to minerals, ceramics and glass. Each is a real run on a planetary ball mill with a matched jar and balls: it shows which set-up and how much time it took to reach the required fineness. This is the practical companion to the mill, jar and media selection guide, which explains how to choose those elements.
Plant and food samples
Soft, fibrous and oily materials grind best dry, in stainless-steel jars. Herbs and green tea give a uniform powder within an hour, while demanding, oily coffee takes about four hours. The keys are the right media charge and cooling pauses, so the sample neither cakes nor overheats.
Pigments, phosphors and functional materials
Where colour purity and freedom from metallic contamination matter, nylon or corundum jars with zirconia balls do the job. A pigment wet-ground reaches the required granularity 100% in about two hours, and a phosphor dry-grinds in a similar time without losing its luminescent properties.
Minerals, ceramics and glass
Hard, abrasive materials need hard jars and longer runs. Active carbon drops to about 2 µm in two hours (corundum jar, zirconia balls), while kaolin reaches ~100 nm in a PTFE liner. Alumina ends up with 87% of the fraction below 5 µm after four hours, and silica (SiO₂) is ground in an agate jar and balls that add no foreign ions.
Results summary
| Material | Jar / balls | Mode | Time | Result |
|---|---|---|---|---|
| Active carbon | corundum / zirconia | dry, 560 rpm | 2 h | ~2 µm |
| Kaolin | PTFE | dry, 450 rpm | 1 h 20 min | ~100 nm |
| Herbs | stainless steel | dry | 1 h | uniform powder |
| Green tea | stainless steel | dry | 1 h | powder meets requirement |
| Coffee | stainless steel | dry | 4 h | fine, uniform powder |
| Pigment | nylon / zirconia | wet | 2 h | 100% meets requirement |
| Phosphor | corundum / zirconia | dry | 2 h | meets requirement |
| Alumina (Al₂O₃) | corundum / zirconia | dry | 4 h | 87% of fraction < 5 µm |
| Silica (SiO₂) | agate / agate | dry | 2 h | meets requirement |
| Glass powder | corundum / zirconia | dry / wet | — | meets requirement |
| Blast-furnace slag | stainless steel | dry | 1 h | meets requirement |
Every run above was carried out on XQM planetary ball mills; the choice of jar and grinding media governed purity and speed. Have your own material to reduce? Write to us — we will match the set-up and, if needed, run a trial grind of your sample.