Ball mill - Wikipedia
A ball mill is a type of grinder used to grind and blend materials for use in mineral dressing processes, paints, pyrotechnics, ceramics and selective laser sintering. It works on the principle of impact and attrition: size reduction is done by impact as the balls drop from near the top of the shell.
Planetary Mills –
Planetary Ball Mills - High-Performance all-rounders in routine laboratory work High-speed and versatile Planetary Mills are ideally suited for fine grinding of hard, medium-hard, soft, brittle, tough and moist materials.