This work presents results on the effect of mischmetal (MM) content on the magnetic properties, phase formation, microstructure, and intergranular interactions in MM_12+xFe_78-xCo₂B₆ (x = 0, 4, 8) magnets. The MM-FeCo-B magnets have been prepared by Spark Plasma Sintering method from powders obtained by grinding precursor nanocrystalline ribbons. A significant increase in coercivity of almost 50%, from 5.4 kOe to 10.2 kOe, has been obtained when the MM content increased from 12 at% to 20 at%, while the remanence decreased with about 30%, from 100.3 to 74.45 emu/g. X-ray diffractograms analysis indicates that for a MM content higher than 12%, in addition to the 2: 14: 1 main phase, secondary phases are formed, the amount of which increases when the MM content increases. Electron microscopy investigations have shown that the secondary phases accumulate at the boundaries of the main phase grains. In the case of the magnet with 20 at% MM content the main phase grains are completely isolated. As a result, the magnets show a weakening of the exchange interaction, explaining thus the increase in coercivity. The best magnetic properties, such as coercivity of about 8.7 kOe and maximum energy product of 11.19 MGOe, have been obtained for the magnet with 16% MM content, which is promising for practical applications in terms of filling the gap between ferrites and Nd-Fe-B magnets.

这项工作提出了关于混合金属（MM）含量对MM _{12 + x} Fe _78-x Co ₂ B _6中磁性能，相形成，微结构和晶间相互作用的影响的结果。（x = 0、4、8）个磁铁。MM-FeCo-B磁体已经通过火花等离子体烧结法从通过研磨前体纳米晶带获得的粉末中制备。当MM含量从12 at％增加到20 at％时，矫顽力显着提高了近50％，从5.4 kOe升高到10.2 kOe，而剩磁从100.3降低到74.45 emu / g，降低了约30％。 。X射线衍射图分析表明，对于MM含量高于12％的材料，除了2：14：1主相之外，还形成了第二相，当MM含量增加时，第二相的数量也增加。电子显微镜研究表明，次级相聚集在主相晶粒的边界处。在具有20 at％MM含量的磁体的情况下，主相晶粒被完全隔离。因此，磁铁显示出交换相互作用的减弱，从而解释了矫顽力的增加。MM含量为16％的磁体具有最佳的磁性能，例如约8.7 kOe的矫顽力和11.19 MGOe的最大能量乘积，就填补铁氧体和Nd-Fe之间的间隙而言，在实际应用中很有希望-B磁铁。