Production of Nanoparticles
with RETSCH Planetary Ball Mills
When producing ultra-fine grinding material with a ball mill, certain stress mechanisms are necessary to ensure that the minute particles can be crushed at all. That is why ultra-fine grinding (colloidal grinding) through mechanical stress is mostly done in liquid media; moreover, it requires a high energy input and pressure and shearing forces which act upon the sample material. The RETSCH Planetary Ball Mill PM 100 meets these requirements. Thanks to the opposite rotation of sun wheel and grinding jar, the large effective sun wheel diameter and the high rotational speed of the sun wheel, the PM 100 possesses the required energy input for the production of nanoparticles.
Eventually, the best possible combination of machine parameters and jar fillings determines the success of a colloidal grinding process. Above all, it is the selection of the grinding jar and the ball filling that has a substantial influence on the grinding results. Grinding jars and beads of zirconium oxide which have a high abrasive wear resistance are especially suitable for ultra-fine grinding.
Tests with quartz have shown that with a speed of 500 rpm, a mean fineness of 0.99 µm is achieved after 30 min. in the PM 100, after 90 min. it is already 0.74 µm.
The excellent mass compensation and the free-force compensation sockets of the PM 100 guarantee a smooth running and safe operation of the mill, even when heavy jar masses have to be moved.
