Effects of Crystallization Conditions on Hard Magnetic Properties of RE-Crystallized Nd-Fe-B Ribbons

The potential of recrystallization of amorphous rare earth-Fe-B materials as a means of obtaining hard magnetic properties is investigated. Amorphous Fe
75
Nd
15
B
10
samples were heated to between 600 and 800°C and held for varying lengths of time before oil-quenching; samples heated to 750°C and immediately quenched showed the highest coercivities. SEM photos and X-ray diffraction studies suggested this was due to precipitation of small Nd
2
Fe
14
B crystals of the sizes of single-domain particles, which contribute greatly to the overall hard magnetic properties.