MM14Fe79.9B6.1/Nd13.5Fe80.5B6 magnets were fabricated by dual alloy method（MM, misch metal）. Some magnets have two Curie temperatures. Curie temperatures Tc1corresponds to the main phase which contains more La Ce, a...MM14Fe79.9B6.1/Nd13.5Fe80.5B6 magnets were fabricated by dual alloy method（MM, misch metal）. Some magnets have two Curie temperatures. Curie temperatures Tc1corresponds to the main phase which contains more La Ce, and Tc1 decreases from 276.5℃ to 256.6℃ 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.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2014CB643702 and 2016YFB0700903)the National Natural Science Foundation of China(Grant No.51590880)the Knowledge Innovation Project of the Chinese Academy of Sciences(Grant No.KJZD-EW-M05)
文摘MM14Fe79.9B6.1/Nd13.5Fe80.5B6 magnets were fabricated by dual alloy method（MM, misch metal）. Some magnets have two Curie temperatures. Curie temperatures Tc1corresponds to the main phase which contains more La Ce, and Tc1 decreases from 276.5℃ to 256.6℃ 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.
