Influence of Ni substitution for B on crystallization behavior, microstructure and magnetic properties of FeBCu alloys

The crystallization, microstructure and magnetic properties of Fe83NixB16-xCu1 (x = 0, 1, 2, 4) alloys are investigated by Mossbauer spectroscopy, X-ray diffractometry and magnetometry. The substitution of Ni for B in the Fe83B16Cu1 alloy enriches Fe clusters in melt-spun ribbons and promotes the nucleation of alpha-Fe(Ni), which is beneficial to the formation of high volume fraction of nanocrystals after crystallization. Furthermore, the addition of 1-2 at.% Ni widens the annealing temperature range for the alloys with low H-C. Excellent magnetic properties with high saturation magnetic flux density (B-s) of 1.83 T and low coercivity (H-C) of 9.2 A/m are obtained by annealing the Fe83Ni2B14Cu1 melt-spun ribbons. In addition, the nanocrystalline alloy with x = 2 possesses a lower saturation magnetostriction (19 ppm) than that of the Ni-free alloy (25 ppm).