Abstract Alloys of Mn-Bi, MnBi-Al and MnBi-Cu were prepared by arc-melting followed by homogenization treatment. All the alloys exhibited hexagonal NiAs crystal structure. Weight fraction of the Low Temperature Phase (LTP) MnBi phase in the Mn-Bi alloy was found to be 88% with a magnetization of 51 emu/gm at 20 kOe, whereas Al and Cu doping resulted in the decrease of the weight fraction of the LTP MnBi phase as well as saturation magnetization. The coercivity is found to increase with the increase in the doping concentration. Upon ball milling the alloys, phase decomposition and a decrease in the magnetization were observed in undoped Mn-Bi alloy. On the other hand, there was no significant phase decomposition and change in the magnetization in doped MnBi alloys due to ball milling. A change in the magneto structural phase transition temperature of MnBi was observed with doping, which is attributed to the lattice modifications occurring in the MnBi system. Doped and undoped Mn-Bi alloys shows increase in coercivity with temperature. Details of investigation are presented in this paper.

中文翻译：

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Al和Cu掺杂MnBi合金的结构和磁性能研究

摘要 采用电弧熔炼和均质化处理制备了Mn-Bi、MnBi-Al和MnBi-Cu合金。所有合金均表现出六方NiAs晶体结构。发现 Mn-Bi 合金中低温相 (LTP) MnBi 相的重量分数为 88%，在 20 kOe 下的磁化强度为 51 emu/gm，而 Al 和 Cu 掺杂导致LTP MnBi 相以及饱和磁化强度。发现矫顽力随着掺杂浓度的增加而增加。在球磨合金时，在未掺杂的 Mn-Bi 合金中观察到相分解和磁化强度降低。另一方面，由于球磨，掺杂的 MnBi 合金中没有显着的相分解和磁化强度变化。掺杂后观察到 MnBi 的磁结构相变温度发生变化，这归因于 MnBi 系统中发生的晶格改性。掺杂和未掺杂的 Mn-Bi 合金的矫顽力随温度增加。本文介绍了调查的详细信息。