MnBi phase evolution during magnetic field assisted annealing studied by in-situ high-energy X-ray diffraction

Ferromagnetic MnBi was synthesized by a solid state processing method (severe plastic deformation using high-pressure torsion). In-situ X-ray diffraction experiments during magnetic field annealing utilizing high energy synchrotron radiation were performed to study the influence of the magnetic field on the evolution of the MnBi phase. Initial MnBi phase formation with a deformation induced texture occurs already during deformation. It was found that the magnetic field has no influence on the orientation of the MnBi grains during annealing, but enhanced the final MnBi phase fraction. Furthermore, the reaction kinetics can be significantly increased compared to other solid state processing techniques.