Fe-Nd-B magnets via the hot extrusion of amorphous powders

This article describes a rapid solidification melt spinning technique has been developed to produce amorphous powders of Fe-Nd-B alloys modified with hafnium diboride. The amorphous powders are consolidated by the hot extrusion technique into bulk magnets of various cross sections. Consolidated magnets show ultrafine grain structure stabilized by ultrafine submicron hafnium diboride particles. The extruded magnets develop strong texture-induced magnetic anisotropy which leads to attractive energy product values of up to 16 MGOe. Significant improvement in coercivity is also achieved due to ultrafine grain structure of the extruded magnets.