Milling Jars
The jar is not just a container. Its material sets your contamination floor, its seal decides whether you can mill under inert atmosphere, and its dimensions have to match your mill. We supply planetary and roller milling jars in zirconia, alumina, stainless steel, PTFE, nylon, and tungsten carbide, from 50 mL to production volumes.
How to choose a milling jar
Match the jar to the media, not just to the sample. Jar and media should be the same material wherever possible. A zirconia jar with steel media contaminates with iron; a steel jar with zirconia media wears the jar. If the two must differ, the jar should be the harder of the pair.
Decide early whether you need an atmosphere seal. Standard jars use a rubber or silicone gasket and are fine for open-air milling. If you are handling air-sensitive materials — sulfide solid electrolytes, lithium metal, most sodium-ion cathodes — you need a gas-tight jar that can be sealed inside a glovebox and stay sealed on the mill. This is not something you can retrofit later.
Fill volume is roughly one third of nominal volume. A 250 mL jar does not mill 250 mL of powder. Media typically occupies a third, sample a third, and the remaining third is the free space the milling action needs. Size up accordingly.
Confirm mechanical fit before ordering. Planetary mills clamp jars by outer diameter and height, and tolerances vary between manufacturers. Tell us your mill make and model and we will confirm fit, or send dimensions if you are working with an older machine.
Send us your mill model, sample chemistry, and batch size and we will specify the jar and matching media set together.
