| 摘 要： | MM_(14)Fe_(79.9)B_(6.1)/Nd_(13.5)Fe_(80.5)B_6 magnets were fabricated by dual alloy method(MM, misch metal). Some magnets have two Curie temperatures. Curie temperatures T_(c1)corresponds to the main phase which contains more La Ce, and T_(c1) decreases from 276.5?C to 256.6?C with the content of MM increasing from 30.3 at.% to 50.6 at.%. The variation of Br with the increase of MM indicates the existence of inter-grain exchange coupling in the magnets. When MM/R ≤ 30.3 at.%,the magnetic properties can reach the level of the intrinsic coercivity Hcj≥ 7.11 kOe and the maximum energy product(BH)max≥ 41 MGOe. Compared with Nd, La and Ce are easier to diffuse to the grain boundaries in the sintering process,and this will cause the decrease of H_(cj) Due to the diffusion between the grains, the atomic ratio of La, Ce, Pr, and Nd in each grain is different and the percentage of Nd in all grains is higher than that in misch metal.
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