112 Prokt. Met. Sonderband 47 (2015)
Der ı
ganel
1. Ein
eit 02
Arbet
GFal¢
Fig. 3: The morphology of the centrifugally atomized NdFeB flake at wheel speed of 280 rpm; SEM micrograph, oo
polished cross section
1. nb
+ ee : Der A
7 Abd
Sampi. 3 Yann
3 AU:
mple 2 BD AN
Sample 1 )
600 1400 1200 -1000 es -600 -400 -200
Fig. 4: B-H curves for samples 1 to 3
4. CONCLUSIONS
Centrifugal atomization technique enables at optimal processing parameters (wheel speed, melting
time) production of NdFeB flakes with optimal microstructure consisting of fine and columnar
grains of main Nd,Fe 4B phase separated by the Nd-rich phase dispersed uniformly along the main
phase which is strongly desirable for preparation of high performance magnets with high
coercivelv
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