Abstract:The grain aggregation and growth of N d-Fe-B permanent magnet alloy in the sintering are studied,it turns out when its shaping ,the orientation of the alloy powder i n the powerful magnetic field result s in the texture in the sintering.Those grains that combine earlier and have almost the same orientation com bine to bigger grains.They eat the sm aller grains around ,forming the pre ternatural big grains.This makes an apparent decrease of the coercive force,and also gives a modific ation to the orientation.So the rema ined magnetic induction intensity is improved slightly,but the maximu m magnetic energy product decreases.The aggregation and growth of grain s in the Nd-Fe-B permanent magnet alloy with the lower Nd,lower oxygen,and the uneven distribution of rich Nd happen easily in higher tem perature.