铸造热压变形Nd-Fe-B永磁合金显微组织和织构的研究

Study on microstructure and magnetic texture of hot-pressing cast NdFeB permanent magnetic alloys

研究了铸造-热压变形Nd Fe B系永磁合金的铸锭组织特征和热压变形过程中组织与织构的变化.

The microstructure features of Nd-Fe-B ingot and the influence of hot-pressing deformation on microstructure and magnetic texture of cast Nd-Fe-B pemanent magnetic alloys were studied.Results show that the growth of Nd_2Fe_(14)B grain during solidification is on sheet-like pattern.The microstructure of Nd-Fe-B ingot has great influence on producing hot-deformed Nd-Fe-B permanent magnetic materials.The molding processing should be improved in order to obtain excellent microstructure with fine and well-aligned colum Nd_2Fe_(14) grains,fine and well-proportioned distribution rich-Nd phase and without α-Fe phase.Hot-pressing deformation refines the grain,and with the increase of strain,the Nd_2Fe_(14)B grains are further refined and the crystal boundary microstructure is improved.The initial texture of Nd-Fe-B alloys is important to form magnetic texture during hot-deformatiion.The well-developed initial texture of Nd-Fe-B permanent magnets can be decreased by hot-pressing deformation,conversely hot-prssing deformation increases the magnetic texture of Nd-Fe-B permanent only when the initial texture is not strengthened.