Unique influence of heating rate on the magnetic softness of Fe81.5Si0.5B4.5P11Cu0.5C2 nanocrystalline alloy

Fe81.5Si0.5B4.5P11Cu0.5C2 nanocrystalline alloy with high Fe concentration possesses a finely uniform nanocrystalline structure and numerous α-Fe crystals with a mean grain size of ∼17 nm based on XRD patterns. Such crystals precipitated from the amorphous matrix. Favorable soft magnetic properties, small value of coercivity (Hc) of ∼4.8 A/m, and high magnetic flux density (Bs) of ∼1.53 T can be achieved by slow heat treatment (heating rate of ∼10 °C/min). In this case, one-step annealing at a low heating rate is truly antipodal to Fe-Si-B-P-Cu alloy. We analyzed the nanocrystallized mechanism during annealing with various heating rates in Fe81.5Si0.5B4.5P11Cu0.5C2 alloy, which inevitably simplified the industrial crystallization process by one-step annealing at a low heating rate.