Sintering method for neodymium iron boron magnet

The invention relates to a sintering method for a neodymium iron boron magnet. The method comprises the processes of: material stacking, first section degassing, second section degassing, sintering and tempering. The method is characterized in that: the method also includes a pre-sintering process between the second section degassing and the sintering processes. By adopting a closed sintering material box, increasing the pre-sintering process, lowering the heating and cooling speed, controlling the degassing temperature and other means, the sintering method provided by the invention reduces the escape speed of hydrogen, greatly reduces the proportion of microcracks on large neodymium iron boron blanks, improves the qualified rate of the blanks, and the blanks can have good magnetic performance.