Unique influence of heating rate on the magnetic softness of Fe_81.5Si_0.5B_4.5P₁₁Cu_0.5C₂ nanocrystalline alloy

Fe_81.5Si_0.5B_4.5P₁₁Cu_0.5C₂ 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 (H_c) of ∼4.8 A/m, and high magnetic flux density (B_s) 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 Fe_81.5Si_0.5B_4.5P₁₁Cu_0.5C₂ alloy, which inevitably simplified the industrial crystallization process by one-step annealing at a low heating rate.