[SOLVED] grinding of MoS2 by a ball mill Hello , Particle size of exist MoS2 is under 30micron and I have to change them to below one micron by a ball mill. I have to use a plastic vial for my application as a mill. I select 40cc plastic bottle as a mill, 48 number of Al2O3 balls (1gr each), 20cc isopropanol alcohol and 3 gr MoS2. Size of the particles were examined each 5 hr by SEM. Unfortunately after 72 hr particles did not have favourable size and many of the particles had large size. Regarding MoS2 has very soft structure (hardness 1-1.5), why I couldn’t get good result? In the wet milling what is good proportion between balls, powder and the liquid?