Abstract：To investigate the optimum diameter of milling balls in preparation of graphene by grinding method, the theoretical diameter of milling balls was calculated according to the principle of stirring ball mill and mechanism of graphene stripping. The optimum diameter of milling balls was verified through a designed experiment. The influence of milling ball diameter in graphene technology on grinding effect was analyzed. The results show that the optimum diameter of milling balls is 100 μm with current experimental conditions. The principle of graphene stripping by grinding method is that the energy that milling balls pass to the graphite flakes should be greater than the binding energy between the graphite flake layers.

Keywords: graphene; grinding method; principle of grinding; diameter of milling ball