Coercivity Enhancement of the Sintered Nd-Fe-B Magnet with Intergranular Multi-Addition
摘要
In order to improve the coercivity of the sintered Nd-Fe-B magnet, a Nd13.5Fe79.75B6.75 magnet with intergranular multi-addition of 2% DyH3, 2% NdH 3 and 1% Nd2O3 is prepared and its magnetic property and microstructure are analyzed. The results show that the coercivity of the magnet with multi-addition is as high as 1300 k A/m, while that of the magnets with DyH3 and Nd2O3 are 520 kA /m and 850 kA /m, respectively. Scanning electron microscope（SEM） shows that the grain boundaries in the magnet with multi-addition are smoother and the grain size is smaller than that in the magnet without the addition. Compared with addition of DyH3 or Nd2O3, the multi-addition can more effectively enhance coercivity of the magnet. Intergranular adding process with multi-addition can both increase the anisotropy field and optimize the grain-boundary microstructure of the magnet. As a result, the coercivity of the magnet is significantly increased.