Crystallization and its kinetics of soft magnetic (Fe1−xNix)79B12P5Si3C1 glassy alloy ribbons

•Glassy FeNiBPSiC alloy ribbons with attractive soft magnetic properties were obtained in melt-spun state.•The partial replacement of Fe by Ni leads to the change from BCC to FCC solid solution in co-precipitated phases.•Ni addition increase the thermal stability of glassy phase and move the isothermal crystallization to SCL region.•The glassy 0.5Ni and 0.6Ni alloys possess the large SCL region, higher GFA and good magnetic softness in the as-spun state