The atomic structure, magnetic properties and bending ductility of a novel Fe-P-C-B-Si amorphous alloy investigated by experiments and ab initio molecular dynamics

The atomic structure, soft magnetic property and bending ductility of Fe-P-C-B-Si amorphous alloys via the change of Si content were investigated. The minor and appropriate Si addition can increase the Curie temperature and saturated magnetization (M_s) effectively. Compared with the 0 at% Si, the M_s of Fe₈₅P₁₀C₂B₂Si₁ and Fe₈₅P₉C₂B₂Si₂ can be enhanced up to 1.58 T and 1.61 T, respectively, which is related to the increase of the total magnetic moments analyzed via ab initio molecular dynamics (AIMD) simulation. Furthermore, the M_s of the annealed amorphous alloys can be continued to increase and the highest M_s of the Fe₈₅P₉C₂B₂Si₂ amorphous alloys can reach up to 1.76 T and the lowest coercivity (H_c) can be reduced to 5.15 A/m after the ribbons were annealed at 627 K. These phenomena are related to the release of inner stress and the formation of α-Fe clusters in amorphous alloys caused by annealing. All ribbons remain good bending ductility annealed at optimal temperature (627 K) determined by M_s and H_c. The combination of high M_s, low H_c, good bending ductility after annealing as well as low production cost and high manufacturability makes the Fe-P-C-B-Si amorphous alloys with high Fe content promising as complement and even replacement of the Si-Fe alloys in magnetic and electric devices.