Two magnets prepared by dual-main-phase (Nd₁₃Fe₈₁B₆ and Dy₂₁Fe₇₃B₆) and single-main-phase (Nd₁₃Fe₈₁B₆ with DyH_x doping) approaches. The content of the Dy element in the composite magnet with dual-main-phase structure (6.75 wt%) is lower than that of the magnet with single-main-phase structure (7 wt%). But the dual-main-phase magnet's coercivity, remanence, and the magnetic energy product are 5.08 kOe, 0.36 kG, and 2.99 MGOe, higher than those of the single-main-phase magnet. In the dual-main-phase magnet, the diffusion of Nd and Dy elements is more prominent. Part Dy element replaces the Nd element to form (Nd, Dy)₂Fe₁₄B phase, and the remaining Dy element exists in the form of Dy₂Fe₁₄B phase, which improves the comprehensive magnetic performance of the magnet. As a result, Dy element in the dual-main-phase magnet is fully utilized. In the single-main-phase magnet, the Dy element replaces the Nd element to form the (Nd, Dy)₂Fe₁₄B phase. However, the remaining non-magnetic Dy element from DyH_x concentrates in the grain boundary, it reduces the magnetic properties of magnets and leads to the waste of Dy elements. The results show that the dual-main-phase structure can control the diffusion of Nd and Dy elements, optimize the distribution of Dy elements, effectively increase the utilization rate of Dy elements and improve the comprehensive magnetic properties of sintered magnets.

由双主相（Nd ₁₃ Fe ₈₁ B ₆和 Dy ₂₁ Fe ₇₃ B ₆）和单主相（Nd ₁₃ Fe ₈₁ B ₆和 DyH _{x ）制备的两个磁体}兴奋剂）方法。双主相结构复合磁体中Dy元素的含量（6.75 wt%）低于单主相结构磁体（7 wt%）。但双主相磁体的矫顽力、剩磁和磁能积分别为5.08 kOe、0.36 kG和2.99 MGOe，高于单主相磁体。在双主相磁体中，Nd和Dy元素的扩散更为突出。部分Dy元素代替Nd元素形成(Nd, Dy) ₂ Fe ₁₄ B相，剩余的Dy元素以Dy ₂ Fe _{14的形式存在}B相，提高了磁体的综合磁性能。结果，双主相磁体中的Dy元素被充分利用。在单主相磁铁中，Dy元素代替Nd元素形成(Nd，Dy) ₂ Fe ₁₄ B相。_{然而，DyH x}中剩余的非磁性Dy元素集中在晶界，降低了磁体的磁性，导致Dy元素的浪费。结果表明，双主相结构可以控制Nd和Dy元素的扩散，优化Dy元素的分布，有效提高Dy元素的利用率，提高烧结磁体的综合磁性能。