Local orientation analysis by electron backscatter diffraction in highly textured sintered, die-upset, and hydrogenation disproportionation desorption and recombination Nd–Fe–B magnets

Abstract

Local texture in polycrystalline Nd–Fe–B powders produced by hydrogenation disproportionation desorption and recombination (HDDR) and by pulverization of hot deformed material (MQA-F) has been studied by electron backscatter diffraction and compared with the ideal case of a powder consisting of single-crystalline particles. The HDDR powder particles exhibited a biaxial {001}, 〈100〉 local texture, whereas the MQA-F particles showed a local 〈001〉 fiber texture. This was explained by differences in the texture mechanisms of the two materials. Resin bonded compacts were prepared from the two polycrystalline powders following alignment in an external magnetic field. The degree of texture on the global scale was determined from magnetic measurements of these compacts and the results were compared with those from a commercial Nd–Fe–B sintered magnet and hot deformed magnet.