Method for preparing Nd based rare earth sintered magnet

摘要

The present invention relates to a method for preparing an Nd based rare earth sintered permanent magnet comprising a step for heating Nd based rare earth alloy powder; a step for coarsely grinding by absorption or hydrogen decrepitation (HD) by adding hydrogen gas to the heated Nd based rare earth alloy powder; a step for fine-grinding the Nd based rare earth alloy powder by repeatedly performing the step of absorption or hydrogen decrepitation by adding hydrogen gas to the heated Nd based rare earth alloy powder; and a step for sintering the fine-ground Nd based rare earth alloy powder. According to the present invention, provided is a method for preparing micropowder of an Nd based rare earth sintered permanent magnet with improved magnetic characteristics by repeating the HD process several times, and an effect of decreasing manufacturing costs and having price competitiveness by being capable of simplifying processes, as a follow-up process of jet milling for preparing fine powder can be omitted.