Usually you use 10-20 times the weight of grinding balls for a serving of powder. Powder plus balls plus water should fill the bottle to about 2/3 full. You should also keep in mind that the diameter of the balls must be at least a factor of 100 larger than the size of the particles to be ground. If your particles are only 10-20 times smaller than the balls (in your case > 0.2 mm), grinding will hardly be possible.

Thanks Vadim Verlotski Sir

Respected Sir,

Generally 10:1 and 5:1 BPR is recommended for low energy ball mills and 100:1 and 50:1 BPR is recommended for high energy ball mills. BPR is also depends upon the material as well as the capacity of the milling jar.

Refer these links for more details:

1. https://doi.org/10.1063/1.3663098

2. https://doi.org/10.1155/2016/7981864

Hope this information is useful.

@Vadim Verlotski Respected sir my powder to be milled is in the range of 1-3 microns but the trouble is for small quantity samples for e.g for 4gm of powder 40/80 gm of tunsten balls wont even cover 1/8th of the 250ml container. So i'll have to increase the ball to powder ratio in a low energy ball mill i.e fill the jar with 40% balls and some 20% ethanol. Btw i was initially gonna dry mill the carbide powders.

Sir @Rayappa Shrinivas Mahale Thank you for the links and guidance.