Preparation method of low-brittleness neodymium iron boron magnetic material

The invention relates to a preparation method of a low-brittleness neodymium iron boron magnetic material. The preparation method comprises the steps of performing raw material vacuum induction and smelting and preparation of alloy slices, hydrogen smashing, air flow milling for preparing powder, magnetic field orientation, pressing and shaping of the powder material, vacuum sintering and aging, material slicing and processing, electroplating and finished product verification. The method is characterized in that a procedure of performing secondary dehydrogenation on the hydrogen smashed powderby a sintering furnace is added after the hydrogen smashing procedure and before the procedure of performing air flow milling to prepare powder in the production process of the existing neodymium iron boron rare earth permanent magnet material, wherein dehydrogenation is performed in conditions as follows: 1-3 heat preservation platforms are set at a temperature of 550-900 DEG C; each platform performs heat preservation