Method For Preparing R-Fe-B Based Sintered Magnet

According to the present invention, disclosed is a method for producing an R-Fe-B-based sintered magnetic substance. The method comprises the steps of : preparing an R-Fe-B-based sintered magnet as a main material; arranging the surface of the main material with at least one rare earth RHX layer of metal dysprosium, hydrogenated dysprosium, terbium, and hydrogenated terbium, and arranging the RHX layer with at least one RLF layer of fluorinated praseodymium, fluorinated neodymium, oxidized praseodymium, and oxidized neodymium; and allowing heavy earth RHX to diffuse into a magnetic substance through the surface of the main material through heat treatment diffusion in a diffusion furnace. According to the present invention, through the arrangement of fluorinated praseodymium, fluorinated neodymium, oxidized praseodymium, and oxidized neodymium on the outer layer of magnetic substance heavy earth RHX, the materials are piled with each other while a magnetic substance is diffused. Thus, adhesion is prevented. On the other hand, the materials are protected not to be oxidized while the heavy earth RHX layer is diffused, and thus the heavy earth RHX layer is prevented from affecting a diffusion effect due to oxidation of the surface of the magnetic substance. At the same time, volatilization of an R element from an R-Fe-B magnetic substance, which is the main material, is prevented during diffusion, and thus residual magnetism of the magnetic substance is rarely reduced.COPYRIGHT KIPO 2018