Properties of Mn-Al-C magnets prepared by spark erosion and other rapid solidification techniques

Abstract

Mn–Al–C was prepared as fine powder by reactive spark erosion and by gas‐water atomization, and in ribbon form by melt spinning. After optimum annealing, coercivities of spark‐eroded particles were higher than those of commercial extruded magnets, but moments were lower. High‐field moments of the atomized particles and melt‐spun ribbons were comparable to those of the extruded magnets, but coercivities and remanences were lower. Differences in the microstructure and phase kinetics among the various Mn–Al–C materials were also substantial.