Glass drops

The big droplets of glass have been pre ground with 20 mm Ø grinding balls for 10 minutes. Because of strong sticking of sample after 2 minutes of dry grinding, we added ~ 45 ml of water and proceed grinding to 10 minutes.

After 10 minutes of grinding time with 20 mm Ø grinding balls, balls have been changed to 5 mm Ø. With the higher amounts of grinding balls, more particles will be comminuted in less time. Also the max. fineness which can be achieved will be finer, compared to results with 20 mm Ø grinding balls.

Because of the high amount of sample, the 80 ml grinding bowl will be filled to the maximum. It might be beneficial using 2 bowls simultaneously and split the sample to 25 g per bowl. Also 1 bowl of 250 ml can be used for a faster grinding result.

After a total of 30 minutes of grinding, sample use to be quite pasty; already 95% of sample use to be < 25 µm. By further grinding, fineness improved only minimal (98% < 25 µm). Longer grinding times are still possible for a finer result.

In this trail, we used zirconium oxide instead of hardmetal tungsten carbide for grinding. Because abrasion of zirconium oxide use to be whitish, no discoloration of sample will be present. Sample use to stay light in color during grinding.

The trial has been performed equally to result 1.

The big droplets of glass have been pre ground with 20 mm Ø grinding balls for 10 minutes. Because of strong sticking of sample after 2 minutes of dry grinding, we added ~ 40 ml of water and proceed grinding to 10 minutes.

After 10 minutes of grinding time with 20 mm Ø grinding balls, balls have been changed to 5 mm Ø.

After a total grinding time of 30 minutes, 100 % of particles use to be < 20 µm as desired. By using a 250 ml grinding bowl, more grinding balls should achieve an equal result in shortened time.