METHOD OF PRODUCING RARE EARTH-TRANSITION METAL-NITROGEN BASED ALLOY POWDER, AND RARE EARTH-TRANSITION METAL-NITROGEN BASED ALLOY POWDER AND BOND MAGNET OBTAINED THEREBY

摘要

PROBLEM TO BE SOLVED: To provide a method of producing rare earth-iron-nitrogen based alloy powder for a magnet which exhibits excellent oxidation resistance and high magnetic properties, and particularly has high orientation properties and high saturation magnetization, and to provide rare earth-iron-nitrogen based alloy powder for a magnet and a bond magnet obtained thereby.;SOLUTION: In the method of producing rare earth-transition metal-nitrogen based alloy powder, using a reducing diffusion method where a mixture consisting of rare earth oxide powder, transition metal powder and a reducing agent is subjected to heating treatment in a non-oxidation atmosphere to cause reducing reaction, so that the rare earth metal is diffused into the transition metal powder, the alloy powder is produced. In this case, the rare earth-transition metal-nitrogen based alloy powder in which an amorphous phase and a micro-ferromagnetic crystal phase with irregular crystal orientation are mixed is coarsely crushed, and thereafter, the alloy powder whose mean grain size is controlled to ≤150 μm is subjected to cracking treatment to obtain the alloy powder comprising alloy grains with a mean grain size of ≥10 μm in which the crystal orientation of the micro-ferromagnetic crystal phase is made uniform by ≥80 vol.%.;COPYRIGHT: (C)2004,JPO&NCIPI