The 2-17 type Sm2-xHRExCo10Cu1.5Fe3.2Zr0.2(HRE=Gd, Tb, Dy, Ho, Er) magnets with low temperature coefficient

Composition and properties of Sm
2-x
HRE
x
CO
10
Cu
1.5
Fe
3.2
Zr
0.2
(HRE=Gd,Tb,Dy,Ho,Er) magnets have been investigated. All alloy powders used in this study were made by the Reduction-Diffusion (R/D) process. The results indicate that Er or Gd-containing magnets have higher magnetic properties than Tb,Dy or Ho-containing magnets. Composition near X=0.8 yields the lowest temperature coefficient. The best properties obtained for a magnet with X=0.8 Er are:
(BH)\max=18.0
MGOe, with a reversible temperature coefficient (α) of nearly zero from 20° to 80°C. A magnet with X=0.4 Er attained values of
(BH)\max=22.6
MGOe and α =-0.018%/° C from 20° to 100°C. A magnet with X=0.58 Gd possesses a
(BH)\max=16.7
MGOe and α =-0.013 %/°C from 20° to 100°C. The magnets with X=2 Er or X=2 Gd have positive α and
(BH)\max
of 4.5 to 4.7 MGOe. These both materials show promise for use in magnetic circuit as temperature compensating magnets.