YH Li, XJ Jia, YQ Xu, et al. Journal of Alloys and Compounds, 2017, 722: 859-863
High saturation magnetic flux density (Bs) soft magnetic nanocrystalline alloys with good manufacturability were developed in a simple Fe-Si-B-Cu alloy system with high Cu concentrations. The nanocrystalline alloys with high Bs of ∼1.77 T and low coercivity of ∼7.1 A/m were obtained by annealing the melt-spun Fe-Si-B-Cu alloys containing 1.7–2.0 at% Cu. The high content of Cu facilitates the formation of high-number-density α-Fe nuclei with an average grain size of ∼6 nm pre-existing in the amorphous matrix, which inhibits the excessive growth of the α-Fe grains by their competitive growth even during the low-heating-rate annealing, resulting in a fine nanostructure and excellent soft magnetic properties.