Method of comminuting rare earth powder for producing rare earth magnet

A method of comminuting rare earth metallic particulate comprising the steps of:

• impacting the particulate against at least one impacting surface in a treatment zone by projecting the particulate under centrifugal force against said surface at a velocity sufficient to cause comminution of at least a portion of the particulate;
• maintaining at least the treatment zone and the impact surface in a temperature range which inhibits oxidation of the particulate while promoting fracture of the particulate;
• and,
• employing an inert gaseous medium in the treatment zone to prohibit combustion of the impacted particulate and having significantly low concentrations of oxygen and water vapor so as to substantially eliminate oxidation of the particulate.