Effect of inhibiting CeFe2 on grain boundary diffusion of Ce/La-Ce containing Nd-Fe-B magnets

Ce and La-Ce containing magnets with the compositions of [(La0.4Ce0.6)(0.3)Nd-0(.7)](31.)5FebalM2.02B0.96 and (Ce0.3Nd0.7)(31.)5FebalM2.02B0.96 were prepared by a grain boundary diffusion (GBD) process with TbHx nanoparticles. After GBD process, the coercivity of Ce containing magnet with CeFe2 phase increases by only 7.2 kOe, while that of La-Ce containing magnet without CeFe2 phase increases by 8.8 kOe. Comparing the two of magnets, some Tb element is consumed in the formation of the (Tb, Ce)Fe-2 phase, therefore reducing the enhancement of the coercivity. It is concluded that inhibiting the CeFe2 phase can promote the diffusion effect of the Tb element in Ce containing magnets. (C) 2019 Elsevier B.V. All rights reserved.