High-energy cast Pr-Fe-B magnets

摘要: A new process has been developed to produce high‐energy bulk Pr‐Fe‐B magnets directly from the melt without handling of magnetic powder or powderlike ribbons. The mainly consists only three steps—casting/hot pressing/annealing—and minimizes oxygen contamination magnets. typical composition cast alloy is Pr17 Fe76.5 B5 Cu1.5 . Using this type alloy, a alignment easily introduced by hot pressing. Copper plays two important roles: high coercivity and excellent are achieved simultaneously addition copper. Magnetic properties hot‐pressed as follows: Br=12.5 kG, i Hc =10.0 kOe, (BH)max =36.2 MGOe. also an 7.4 kOe 8.8 MGOe after annealing at 1000 °C for 24 h. steep rise in initial magnetization curve indicates nucleation‐controlled mechanism.