Effect of Co Content on the Soft Magnetic Properties and Bending Ductility of FeCoPB Amorphous Alloys

Fe-Co-P-B amorphous alloys with high FeCo contents ( up to 87at%) were synthesized by melt spinning method. The effects of the metallic element Co on glass formation ability (GFA), thermal stability, and magnetic properties of Fe- Co-P-B amorphous alloys were investigated in details. Fe87-xCoxP2B11 (x=5-7) amorphous alloys have high saturated magnetization (from 1.75 T to 1.84 T) and good bending ductility even after annealing. The Curie temperature (T-c) of the present Fe-Co-P-B alloys obviously increases with the substitution of Fe by Co, and the coercivity (H-c) increases. The tensile stress applied to the Fe-based amorphous alloys can obviously reduce H-c from 12.8 A/ m to 6.5 A/m with the tensile stress change from 0 to 12 MPa. The optimal adjustment of both the alloy composition and stress provides an important way to obtain Fe-based amorphous with both excellent soft-magnetic properties and good bending ductility, which can avoid annealing-induced embrittlement.

Automated summary

Fe-Co-P-B amorphous alloys with high FeCo contents (up to 87at%) were synthesized. The effects of Co on GFA, thermal stability, and magnetic properties were investigated. Fe87-xCoxP2B11 amorphous alloys have high magnetization and good bending ductility. The substitution of Fe by Co increases Curie temperature and coercivity, while applied tensile stress can reduce coercivity.