Abstract Nd-Fe-B based magnets possess the largest energy product and are essential in numerous cutting-edge applications. We report the bottom up, energy efficient, cost effective microwave synthesis of Dy alloyed Nd2(Fe,Co)14B magnetic nanoparticles. The process included microwave combustion to synthesize Nd-Dy-Fe-Co-B mixed oxides, followed by the reduction of these oxides by CaH2. The influence of Dy substitution on both room temperature and temperature dependent magnetic properties were investigated. For (Nd12Dy3)-(Fe67Co10)-B8 alloy, (BH)max was found to be as high as 12.6 MGOe. The coercivity increased significantly, from 8 kOe to 14.5 kOe, as Dy content increased from x = 0 to x = 9. The thermal coefficient of remanence (α) and thermal coefficient of coercivity (β) were also determined, it was found that thermal stability increased for higher Dy content. Analysis of temperature dependent magnetic properties and comparison with modeling results showed that the dominant coercivity reversal mechanism of these particles was nucleation of reversed magnetic domains.

中文翻译：

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Dy 取代对微波处理制备的高 (BH)max Nd-Dy-Fe-Co-B 纳米颗粒的微观结构和磁性能的影响

摘要 Nd-Fe-B 基磁体具有最大的能量积，在众多尖端应用中必不可少。我们报告了 Dy 合金化 Nd2(Fe,Co)14B 磁性纳米粒子的自下而上、节能、经济高效的微波合成。该过程包括微波燃烧以合成 Nd-Dy-Fe-Co-B 混合氧化物，然后用 CaH2 还原这些氧化物。研究了 Dy 取代对室温和温度相关磁性能的影响。对于 (Nd12Dy3)-(Fe67Co10)-B8 合金，发现 (BH)max 高达 12.6 MGOe。随着 Dy 含量从 x = 0 增加到 x = 9，矫顽力显着增加，从 8 kOe 增加到 14.5 kOe。还确定了剩磁热系数 (α) 和矫顽力热系数 (β)，发现较高的 Dy 含量增加了热稳定性。温度相关磁特性的分析以及与建模结果的比较表明，这些粒子的主要矫顽力反转机制是反转磁畴的成核。