Synthesis and characterisation of (Fe,Co)2-3B microcrystalline alloys

The promising high magnetocrystalline anisotropy of about K1 > 0.4 MJ/m3 has been derived for (Fe,Co)2-3B melt-spun ribbons leading to a potential candidate for novel hard magnetic applications. We present the microstructural and magnetic analysis of the phase relations in various microcrystalline alloys with a nominal composition of (Fe1−xCox)71B29 (0 ⩽ x ⩽ 1) by means of SEM and TEM investigations. The melt-spun ribbons were prepared at different wheel speeds (18-38 m/s) and annealed at 500 °C for one hour. The optimum hard magnetic properties were obtained for (Fe0.7Co0.3)71B29 at 26.7 m/s. The crystal anisotropy and saturation polarisation have been confirmed by DFT calculations.