Effect of Fe doping on the magnetic properties of MnBi alloy

Structure and magnetic properties of Fe-doped MnBi alloy with a range of Fe concentrations were systematically investigated. The coercive field and saturation magnetization (M-s) were drastically changed according to the fabrication methods and Fe contents. The addition of Fe element could enhance the coercivity (H-c) of the MnBi-based alloy, and the increased H-c of 1.76 T was reached in the Mn55Bi45-Fe (15 wt%) ball-milled ribbon. Moreover, a high remanence ratio (M-r/M-s) of 97.0% was achieved in the Mn55Bi45-Fe (7.5 wt%) ball-milled ingot. In addition, as the concentration of Fe increases from 0 to 15 wt%, the Curie temperature (T-c) was increased from 635 to 652 K. This demonstrates that Fe-doped MnBi rare-earth permanent magnets could be a promising candidate for high-temperature applications. The relationship between magnetic properties and intermetallic lattice variations were discussed with precise Rietveld refinement analysis. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The structure and magnetic properties of Fe-doped MnBi alloy with different Fe concentrations were systematically investigated, showing that the addition of Fe can enhance the coercive force and achieve different magnetic performances in ball-milled ribbon and ingot. As the Fe concentration increases, the Curie temperature of the alloy also gradually rises.