Abstract: Low-cost Fe₈₀P_12-xC₈Bx (x = 0, 1, 2, 3 and 4 at.%) bulk metallic glasses (BMGs) with good soft magnetic and mechanical properties were prepared, and effects of metalloid B addition on the glass-forming ability (GFA) as well as thermal, magnetic, and mechanical properties of the BMGs were investigated. It was found that the proper B substitution for P improves the GFA of the Fe-P-C BMGs. The alloy with 2 at.% B addition manifests the highest GFA with critical diameter for glass formation of 2 mm. Besides, these BMGs exhibit good soft magnetic properties featured by high saturation magnetization of 1.35-1.57 T and low coercivity of 2.2-7.7 A/m as well as unique mechanical properties of high fracture strength of ～3.3 GPa and visible plastic strain of 0.4%-2.5%. The combination of high GFA, good soft magnetic and mechanical properties as well as low cost makes the present Fe-P-C-B BMGs promising as soft magnetic materials for industrial applications.

Key words: Bulk metallic glasses, Glass-forming ability, Magnetic properties, Mechanical properties