Revealing the Impact of Ferromagnetic Elements on Fe-Based Amorphous Alloy Properties via ab initio molecular dynamics simulations and Experiments

High saturation magnetic flux density (B_s) is essential for the development of Fe-based amorphous alloys in electromagnetic devices and motors. However, achieving high B_s often compromises the glass-forming ability (GFA) of Fe-based amorphous alloys. This study investigates the effects of ferromagnetic elements (Fe, Co, and Ni) on the microstructure and magnetic properties of Fe₈₆B₇C₇ amorphous alloys through both experiments and ab initio molecular dynamics simulations. By analyzing both experimental and simulation results, the relationship is explored between atomic structures, GFA, and magnetic properties of these amorphous alloys. The research indicates that the GFA of the alloys is correlated with the proportion of icosahedral clusters and body-centered cubic clusters. The addition of Co and Ni not only improves the GFA of alloys, but also effectively increases the overall magnetic moment with an appropriate amount of Co and a minor amount of Ni. This increase in magnetic moment primarily arises from the enhancement of the magnetic moment of Fe atoms, resulting from the redistribution between the spin-up and spin-down electrons of Fe-3d orbits, as well as the strong exchange interactions between Fe-Co and Fe-Ni pairs. The results obtained offer valuable insights into the correlation between atomic structure and magnetic properties in these amorphous alloys, and suggest potential directions for the optimization of Fe-based amorphous alloys.