A high magnetic energy product obtained in hot-deformed Nd-Fe-B magnet by chemical plating Fe-Co bilayer films

This study investigates a novel method, chemical plating, with the goal of integrating nano-sized ferromagnetic materials into hot-deformed Nd-Fe-B magnets, potentially enhancing their magnetic properties. Coating Fe-Co double layers on Nd-Fe-B magnetic powder resulted in a significant improvement in the remanence over 10 %, increasing from 1.37 to 1.45 T, as well as an increase in the maximum magnetic energy product from 45.95 to 52.02 MGOe in hot-deformed Nd-Fe-B magnets. Microstructure observations revealed that the coarse nonoriented grains at the interface of powder ribbons were suppressed and the texture of grain alignment in the interior of powder ribbons was enhanced after the coating of Fe-Co. Additionally, there was a noticeable increase in the concentrations of ferromagnetic elements in intergranular phases. The reduced coarse grain regions, the enhanced grain alignment and the increased ferromagnetic intergranular phases are considered to be the main reasons for the enhancement of remanence and maximum magnetic energy product in hot-deformed magnets.