Abstract In this work, the microstructure, phase transformation and magnetic properties of MnAl permanent magnetic alloys prepared by the melt-spinning technique were systematically investigated by tuning the cooling rate. It was shown that the MnAl microstructure, phase transformation and magnetic properties can be tailored by the copper roller speed. With increasing of the roller speed, the phase transformation from the γ2, β phases to the e phase was observed. In addition, the variation of magnetic properties was attributed to the phase content and microstructure of the ferromagnetic τ phase in the MnAl alloys, being controlled by the cooling rate. As a result, the high-purity τ phase MnAl was obtained at a copper roller speed of 5 m/s, which exhibited a high magnetization of 118.2 emu/g. Therefore, this work can provide a method for the direct fabrication of the high-purity ferromagnetic τ phase MnAl alloy.

中文翻译：

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冷却速度对MnAl永磁合金组织和磁性能的影响

摘要 本工作通过调节冷却速率系统地研究了熔纺技术制备的MnAl永磁合金的显微组织、相变和磁性能。结果表明，MnAl 微观结构、相变和磁性能可以通过铜辊速度进行调整。随着轧辊速度的增加，观察到从γ2、β相到e相的相变。此外，磁性能的变化归因于MnAl合金中铁磁τ相的相含量和微观结构，受冷却速率控制。结果，在5m/s的铜辊速度下获得高纯度τ相MnAl，其表现出118.2emu/g的高磁化强度。所以，