Screw-top grinding jars are dust- and air-tight which makes them suitable for dry, wet and cryogenic grinding. Moreover, they safely enclose inert atmosphere, for example after the jar was filled inside a glove box.
Always select a grinding jar size suitable for the sample volume (approx. 30% of the jar is filled with sample material). Grinding jars are provided in sizes ranging from 1,5 ml to 50 ml (not all sizes available in all materials).
The document “Grinding Jar Ball Charge” in the Downloads section provides details about usable volumes, maximum feed sizes and correct filling of the jars with grinding balls for dry and wet milling as well as cell disruption.
For efficient and contamination-free grinding processes the grinding jars are available in 6 different materials (no undesired abrasion).
The energy input increases with the density of a material. For pulverizing soft samples, materials with a low to medium density should be used, whereas for hard samples it is better to use high-density materials.
Available materials:
- Hardened steel (density 7.8 g/cm3; hardness ≤ 235 HB, medium abrasion resistance)
typically used for pulverizing medium-hard to hard and brittle samples.
- Stainless steel (density 7.7 g/cm3; hardness ≤ 245 HB, medium abrasion resistance)
typically used for pulverizing medium-hard to hard and brittle samples.
- Tungsten carbide (density 14.8 g/cm3; hardness 93.6 HRA; high abrasion resistance)
used for grinding very hard, brittle sample materials. By using tungsten carbide, contamination of the sample with iron is prevented.
- Agate (density 2.6 g/cm3; hardness 6.5 – 7 Mohs, low abrasion resistance)
a highly pure natural material suitable for pulverizing soft to medium-hard or fibrous samples. Due to its low-density agate is suitable for gentle grinding processes with low energy input.
- Zirconium oxide (density 6.05 g/cm3; hardness 1250 HV, high abrasion resistance)
ceramic material suitable for pulverizing medium-hard to hard and fibrous samples. It is typically used for heavy-metal-free grinding processes or applications which aim at ultrafine particle sizes.