SURFACE TREATMENT OF RARE EARTH-FE-B MAGNET

摘要: PURPOSE:To improve an anticorrosive effect by dipping a rare earth-Fe-B magnet obtained sintering pressed-powder substance of alloy powder into acid water solution followed heat treatment. CONSTITUTION:A having earth elements B and Fe including Y as necessary is dipped This contains 1 to 20volume% one kind or more hydrochloric sulfuric acid, nitric phosphoric hydrofluoric organic carboxylic while being at liquid temperature 0 50 deg.C for 30min. Next, treatment performed in vacuum inactive gas atmosphere 300 900 deg.C. Thereby, passivating oxide film formed on the surface so that improved.