1.2.1.2.7 Magnetocrystalline anisotropy

Influence of microstructure on the enhancement of soft magnetic character and the induced anisotropy of field annealed HITPERM-type alloys

“…A simple calculation imposing K 1 $ 10 kJ/m 3 (Ref. 15) for a Fe 0.61 Co 0.39 composition and the microstructural parameters collected in Table I leads to a value of A $ 0.5 Â 10 À11 J/m, which is in good agreement with the expected value.…”

“…The value of K 1 depends on the composition of the a-FeCo phase, being $50 kJ/m 3 for pure a-Fe and decreasing as Co content increases down to $À40 kJ/m 3 for 70 at. % Co. 15 Therefore, assuming that the compositions of nanocrystals are Fe 0.61 Co 0.39 and Fe 0.4 Co 0.6 for the alloys with 39 and 60 at. % Co, respectively, 16 K 1 can be estimated as $þ10 kJ/m 3 and À20 kJ/m 3 for x ¼ 39 and 60 alloys, respectively, 15 which explains the observed difference.…”

“…% Co. 15 Therefore, assuming that the compositions of nanocrystals are Fe 0.61 Co 0.39 and Fe 0.4 Co 0.6 for the alloys with 39 and 60 at. % Co, respectively, 16 K 1 can be estimated as $þ10 kJ/m 3 and À20 kJ/m 3 for x ¼ 39 and 60 alloys, respectively, 15 which explains the observed difference. Figure 2 shows the hysteresis loops of TF annealed samples, which show sheared loops, almost linear up to the anisotropy field, H k , where M S is reached.…”