High-energy planetary ball milling apparatus and method for the preparation of nanometer-sized powders

A method for producing nanometer-scaled powders, comprising:

• (a) providing micron- or millimeter-sized starting powders and selected numbers of grinding balls sealed in a plurality of mill pots which are driven by a main rotary wheel to undergo a primary rotational motion;
• (b) providing a non-revolvable counter-acting supporting ring disposed coaxially with said main rotary wheel and in the close, working proximity to said mill pots;
• (c) providing each said mill pot with rotary coupling means to enable a planetary rotation of each said mill pot about its own axis, and a pivotal shaft being capable of tilting each said mill pot toward said supporting ring permitting each said mill pot to periodically contact therewith, thereby inducing said planetary motion of each said mill pot when undergoing said primary rotational motion;
• and
• (d) using motor means to drive said primary rotational motion and the induced planetary motions for a predetermined period of time, stopping all said motions, and removing resulting fine powders from said mill pots.

A planetary ball mill apparatus for producing nanometer-scaled powders, comprising:

• (a) a main rotary base comprising supporting members;
• (b) a plurality of mill pots which are revolvable by receiving a rotational force from said rotary base, said pots being disposed around and above said rotary base with substantially equal distance between one mill pot and another, each said mill pot comprising a shaft, a tilting mechanism and rotary coupling means so that each said pot can rotate about its own axis, and each said shaft having one end being supportably connected to one of said supporting members of the rotary base;
• (c) motor means in drive relation to said rotary base for providing rotational forces thereto;
• and
• (d) at least one non-revolvable counter-acting supporting ring disposed coaxially with said main rotary wheel and in the close, working proximity to said mill pots;
• each said tilting mechanism being capable of permitting its corresponding mill pot to periodically contact with said non-revolvable supporting ring, thereby inducing a planetary motion of said mill pot about its own axis.