Preparation method of neodymium iron boron magnetic material

The invention belongs to the technical field of materials, and particularly relates to a preparation method of a neodymium-iron-boron magnetic material, which comprises the following steps: crushing ferric oxide, screening, removing impurities, putting into a ball mill, filling absolute ethyl alcohol into the ball mill, and grinding and crushing; when the ferric oxide is ground and crushed, neodymium oxide and aluminum tetraoxide with corresponding components are added in batches, then discharged liquid is distilled, and absolute ethyl alcohol is recycled; and drying the ball-milled mixture, filling powder at the screened part into a female die on a forging press, driving a sliding block and a male die to slide downwards in cooperation with a main oil cylinder, maintaining the pressure of the male die in cooperation with an electromagnet, and carrying out high-temperature and high-pressure compression molding on the powder, so that the neodymium-iron-boron magnetic material can be obtained. The absolute ethyl