MnBi/Sm2Co17复合磁粉制备、磁性能及微结构研究

Shan Jiefeng 1, Yu Nengjun1, Zhang Suyin1, Jin Xiangyang2, Wu Qiong1, Zhang Pengyue1, Ge Hongliang1

摘要:

采用化学辅助高能球磨工艺制备了MnBi/Sm₂Co₁₇纳米晶复合磁粉,研究了MnBi合金添加量对复合磁体磁性能和微结构的影响。随着MnBi合金添加量的增加,复合磁粉的内禀矫顽力先稍上升,后基本保持不变,但均低于纯MnBi磁粉的10.8 kOe；磁粉的饱和磁化强度和剩余磁化强度均逐渐下降。复合磁粉中没有发现明显的元素互扩散现象。采用Henkel曲线分析了复合磁体的交换耦合作用,复合磁粉的δM在添加量为15wt. %时达到极大值,说明该复合磁体具有较强的交换耦合作用,结合磁粉形貌分析了随着MnBi合金添加量的增加复合磁粉剩磁比演变规律的原因。

Abstract:

The MnBi/Sm₂Co₁₇ composite powder was prepared by chemically assisted high-energy ball milling process, and the effect of the content of MnBi alloy on the magnetic properties and microstructure of the composite powder has been studied. As the content of MnBi alloy increases, the coercivity of the composite powder first increases slightly, and then keep stable at about 8.0 kOe, while coercivity of all the composite powder was lower than 10.8 kOe of pure MnBi milled powder; the saturation magnetization and remanent magnetization of the composite powder gradually decreased. No obvious elements interdiffusion was found in the composite magnetic powder. The exchange coupling effect of the composite powder was analyzed by the Henkel curve. The δM of the composite magnetic powder reaches the maximum value when the MnBi addition amount was 15wt.%, indicating that the composite powder has a strong exchange coupling effect. The evolution of the remanence ratio of the composite magnetic powder with the increase of MnBi alloy content has been analyzed depending on the morphology and the exchange coupling effect of the composite magnetic powder.