The invention discloses a method for crushing a sintered
neodymium-iron-
boron magnet through jet milling by using
neon. Firstly,
magnet coarse particles subjected to
hydrogen decrepitation treatment are placed in a
jet mill grinding chamber, then
neon flowing at a high speed is introduced,
powder particles are further crushed and enter a sorting device by adjusting the
neon flowing speed and the ventilation time, particles larger than the specified size return and continue to be crushed,
powder smaller than the specified size is separated, and particles with too small sizes are removed; and finally,
powder with the particle size of 2.5-4 microns is obtained. Compared with a traditional
airflow milling method using
nitrogen, the neon gas is adopted, the powder particle size is successfully controlled within the ideal single domain critical size range, and meanwhile the powder flowability and the filling density are improved. The process compatibility and the forming efficiency of the
magnetic powder in the subsequent
magnetic field orientation and pressing forming process are remarkably improved, the nitridation reaction of
rare earth elements is avoided due to the chemical inertness of neon, the
nitrogen content of the
magnetic powder is remarkably reduced, and a foundation is laid for obtaining a
magnet with better performance.