80 ml grinding bowl made of hardmetal tungsten carbide (WC)
+ 30x10 mm WC-balls
Feed quantity:
4,92 g
Feed Size:
< 120 µm
Additive:
+ 8ml water
Grinding time:
120 min
Final fineness:
flocculating
Comments:
To avoid overpressure, we ground the sample in steps of 5 minutes, followed by a programmed pausing time of 10 minutes. After several cycles, the outside temperature of the bowl should be checked (remain below 80°C); grinding time or programmed pausing time might be readjusted afterwards.
After 30 min of grinding, the sample started to build small flakes with up to 1,5mm. After 2 h of grinding we obtained a gray emulsion including gold-flakes (probably due to the abrasion of tungsten carbide).