Axial Pressing Method Using Pulse Magnetizing Field for the Preparation of Nd-Fe-B Sintered Magnets

A new axial pressing method using pulse magnetizing field was studied to improve the remanence of Nd-Fe-B sintered magnets. In pulsed axial die pressing(PADP) process , tapping density of powders, method of pulse supply and strength of pulse field were optimized to increase magnetic alignment and remanence. As a results, we could find that an axial pressing under pulse magnetizing field was very effective to increase the degree of magnetic alignment of powder, yielding remanences even higher than those obtained by the transverse die pressing. The remanence of 14.1 kG was easily obtained by PADP process from 31R-68TM-1B (in wt.%) sintered magnet