Rare-earth free MnBi magnets produced by laser powder bed fusion

In this study, we show for the first time that it is possible to manufacture the rare-earth free magnetic α-MnBi phase directly using laser powder bed fusion of elemental Mn and Bi powder mixtures. We further present an analysis of the impact of printing parameters on α-MnBi phase formation and microstructure, and subsequently on the magnetic properties. In the as-printed state, up to 50wt.% α-MnBi phase is formed. After annealing, α-MnBi phase content increases. Compared to ambient temperature, the magnetic properties significantly improved at elevated temperature.