The invention discloses a GaCu co-doped sintered permanent
magnet and a production process, the GaCu co-doped sintered permanent
magnet comprises the following components in percentage by weight: 25-35 wt% of Ce, 15-25 wt% of Nd + Pr, 0.9-1.1 wt% of B, 0.2-0.3 wt% of Ga, 0.1-0.2 wt% of Cu and the balance of Fe, and the production process comprises the following steps: S1,
smelting raw materials; s2,
powder is prepared, treatment is conducted for 2.5-3.5 hours under the
hydrogen atmosphere at the pressure of 0.1-0.2 MPa and the temperature of 300 DEG C, then
airflow milling is conducted under
inert gas protection, and anisotropic
powder with the average particle size being 3-5 microns is obtained; s3, pressing and forming; and S4,
vacuum sintering: pre-
sintering the pressed blank under a vacuum condition at the pre-
sintering temperature of 600-700 DEG C and the heat preservation time of 0.8-1.2 hours, continuously heating to 1040-1080 DEG C, preserving the heat for 2-4 hours, then cooling to 500-600 DEG C, preserving the heat for 1-2 hours, and cooling to obtain the GaCu co-doped sintered permanent
magnet. GaCu is doped, and spontaneous
passivation of a
grain boundary is realized in the
vacuum sintering and low-temperature annealing processes, so that the
corrosion resistance and the
structural stability of the magnet are remarkably improved under the plating-free condition.