Abstract Chemical synthesis of Nd2Fe14B hard magnetic powders are still hindered due to the complicated methods. Herein, we put forward a modified sol–gel strategy to prepare Nd2Fe14B magnetic powders with excellent magnetic properties. In this synthesis procedure, acetone and boric acid are simultaneously used as the coordination reagents. The formation mechanisms of the oxide precursors as well as the effect of the reduction-diffusion temperature on the composition and magnetic properties of the products have been investigated. Magnetic properties measurement shows that the sample prepared at 950 °C possess the highest coercivity value of ~4.8 kOe. The Henkel plots and recoil loops suggest that the existence of α-Fe is responsible for the stronger exchange-coupling behavior and better magnetic performance.

中文翻译：

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Nd2Fe14B硬磁粉：化学合成及矫顽力机理

摘要 由于方法复杂，化学合成Nd2Fe14B硬磁粉仍然受到阻碍。在此，我们提出了一种改进的溶胶-凝胶策略来制备具有优异磁性能的 Nd2Fe14B 磁粉。在该合成过程中，丙酮和硼酸同时用作配位剂。研究了氧化物前驱体的形成机制以及还原扩散温度对产物组成和磁性能的影响。磁性能测量表明，在 950 °C 下制备的样品具有~4.8 kOe 的最高矫顽力值。Henkel 图和反冲回路表明 α-Fe 的存在是导致更强的交换耦合行为和更好的磁性能的原因。