Method for press molding rare earth alloy powder and method for producing sintered object of rare ea
2022-07-31
2930
766K
0
A perpendicular pressing/compacting method for a rare-earth alloy powder is provided to produce a sintered magnet with excellent magnetic properties. A method for pressing a rare-earth alloy powder by using a die is provided. The die is made of a non-magnetic material and has a die hole to define a cavity and a pair of yoke members provided on both sides of the cavity. The method includes the steps of : providing the rare-earth alloy powder; filling the cavity of the die with the rare-earth alloy powder; and compressing the rare-earth alloy powder, loaded in the cavity, between a pair of opposed press surfaces. A pulse magnetic field substantially perpendicular to a compressing direction is not applied until the apparent density of the rare-earth alloy powder in the cavity reaches a predetermined value, at least equal to 47% of the true density thereof, while the compressing step is being carried out.