Formation and Structural Evolution of Fe_(72.5)B_(15.6)Si_(7.8)Nb_(1.7)Zr_(1.7)Cu_(0.7) Nanocrystalline Alloy

A 2.5-mm Fe_72.5B_15.6Si_7.8Nb_1.7Zr_1.7Cu_0.7 glassy rod was successfully fabricated using copper mold casting. The introduction of Cu resulted in the formation of large quantities of α-Fe nanoparticles embedded in the glassy matrix after isothermal annealing. The Fe_72.5B_15.6Si_7.8Nb_1.7Zr_1.7Cu_0.7 nanocrystalline alloy exhibited high saturation magnetization (~ 1.26 T) and a low coercive force (~ 0.8 A/m) after annealing at 833 K for 15 min due to the precipitation of ~ 15-nm-sized α-Fe nanoparticles in the glassy matrix. The structural evolution of the FeBSiNbZrCu amorphous alloy during the annealing process was discussed using a dual-cluster model.