On the correlation between glass forming ability (GFA) and soft magnetism of Ni-substituted Fe-based metallic glassy alloys

•Impact of ferrous Ni on the mechanism of glass formation in Fe-based glassy alloys.•Correlation between glass formation and soft magnetism of glassy alloys.•Monotonic increase of Curie point by reduced antiferromagnetic Fe-Fe interactions in iron-rich glassy matrix. The present work aims to investigate the mechanism of glass formation and correlates it to the soft magnetism of Ni-substituted Fe-B-Nb alloys. The impact of ferrous Ni on the mechanism of glass formation and soft magnetism of Fe-based bulk metallic glasses was critically analyzed. By quantifying glass forming ability and soft magnetic characteristic for varying degrees of substitution, we observe a maximum in glass forming ability together with a minimum coercivity, which we suggest is due to an increased atomic packing density of the glassy phase. Interestingly, a monotonic increase of Curie temperature with increasing substitution of Ni was observed, which could be attributed to a reduction of an antiferromagnetic Fe-Fe interaction in the glassy iron-rich matrix. The overarching goal of this study is to explore the underlying mechanisms of enhanced glass forming ability, improved soft magnetic properties, and increased Tc of Ni-substituted Fe-based glassy alloys.