The formation of single-phase equiatomic MnBi by rapid solidification

The low temperature phase (LTP) of MnBi, which is of interest because of its large magnetic anisotropy, has been obtained in almost single-phase form (>95%) by rapid solidification, followed by thermal annealing. X-ray and electron microscope studies indicate that the melt-spun ribbons are amorphous, contrary to the accepted rules for glass formation. The transformation of the amorphous phase is a complex process. The amorphous phase crystallizes first into Bi, Mn₃Bi, and ferrimagnetic MnBi. The formation of the LTP begins immediately after the eutectic melting of these phases around 540 K.