The widespread adoption of Nd-Fe-B magnets with abundant and cheap Ce substitution for Nd is significantly constrained by the inherently inferior magnetic properties exhibited by Ce-Fe-B. In this study, high-performance Nd-Ce-Fe-B sintered magnets with Nd-Fe-B + Ce-Fe-B (N-C-type) and Nd-Fe-B + (Nd, Ce)-Fe-B (N-NC-type) compositions are successfully developed through the design of dual-alloy components, which facilitate precise control over the distribution of rare-earth (RE) elements in the dual-main-phase grains. The N-C-type exhibits higher remanence (Br) and magnetic energy product [(BH)max], whereas the N-NC-type demonstrates higher coercivity (Hcj). The magnetic properties of the as-sintered magnet with 20 wt.% of Ce over the total RE content are optimized via Br of 14.25 kG, Hcj of 8.6 kOe, and (BH)max of 48.6 MGOe. After annealing, Hcj increases to greater than 10 kOe and (BH)max remains at 47 MGOe. Through the implementation of reasonable composition design and the optimization the preparation processes in these grains, the RE elements exhibit a clear stepwise heterogeneity of the chemical composition in their core-shell structure, whereas the shell structures of these grains display a homogeneity of chemical composition. The results provide a reference for the composition design and development of high-performance high-abundance RE sintered magnets for enhancing the utilization of high-abundance RE elements in permanent magnetic materials and contributing to a more balanced exploitation of RE resources.

中文翻译：

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高性能高丰度稀土烧结磁体的相组成定制和矫顽力机理


Nd-Fe-B 磁体的广泛采用具有丰富且廉价的 Ce 替代 Nd，这在很大程度上受到了 Ce-Fe-B 固有的劣质磁性的制约。在本研究中，通过双合金成分的设计，成功开发了具有 Nd-Fe-B + Ce-Fe-B（N-C 型）和 Nd-Fe-B + （Nd，Ce）-Fe-B（N-NC 型）成分的高性能 Nd-Ce-Fe-B 烧结磁体，这有助于精确控制稀土 （RE） 元素在双主相晶粒中的分布。N-C 型表现出更高的剩磁 （Br） 和磁能积 [（BH）max]，而 N-NC 型表现出更高的矫顽力 （Hcj）。烧结磁体的磁性能在总 RE 含量中为 20 wt.% Ce，通过 14.25 kG的 Br、8.6 kOe 的 Hcj 和 48.6 MGOe 的 （BH）max 进行优化。退火后，Hcj 增加到大于 10 kOe，（BH）max 保持在 47 MGOe。通过实施合理的成分设计和优化这些颗粒中的制备工艺，RE 元素在其核壳结构中表现出明显的化学成分逐步异质性，而这些颗粒的壳结构表现出化学成分的均匀性。研究结果为高性能高丰度稀土烧结磁体的成分设计和开发提供了参考，以提高永磁材料中高丰度稀土元素的利用率，有助于更均衡地开发稀土资源。