Electronic structures of nanocrystalline Fe90-xCuxSi10-yBy soft magnets

Abstract

We have calculated electronic structures of nanocrystalline Fe90−xCuxSi10−yBy using first principles calculations based on density functional theory (DFT) to obtain saturation magnetic flux density (Bs). The Bs of crystalline (Fe3Si) and amorphous (Fe-B) phases in Fe90−xCuxSi10−yBy were separately calculated, and the total Bs of Fe90−xCuxSi10−yBy was derived by the summation of the Bs for the Fe3Si and Fe-B phases. The calculated Bs of Fe3Si is 1.35 T, and that of Fe-B varies from 2.08 to 2.22 T based on Fe to B ratios. Therefore, a total Bs higher than 1.80 T can be obtained with y ≥ 4 for both x = 1 and 2 in Fe90−xCuxSi10−yBy.