Reducing the annealing heating rate sensitivity of Fe_83.5Si₃B₁₀P₂Cu_1.5 soft magnetic nanocrystalline alloy by adjusting the melt spinning cooling rate

This work investigates the effect of the microstructure of the as-quenched precursors prepared at various cooling rates on the soft magnetic characteristics and its sensitivity to the annealing heat rate (HR) of the Fe_83.5Si₃B₁₀P₂Cu_1.5 nanocrystalline alloy. The results of Mössbauer spectra indicate that the cooling rate during the melt spinning process significantly impact the microstructure of as-quenched alloy samples. The decrease in the cooling rate facilitates the formation of an amorphous/nanocrystalline precursor containing more “α-Fe-like” structure and Cu-clusters. Variations of grain size and H_c with heating rate indicate that Fe_83.5Si₃B₁₀P₂Cu_1.5 alloy samples prepared at a low cooling rate are less sensitive to the heating rate during crystallization annealing. The Fe_83.5Si₃B₁₀P₂Cu_1.5 nanocrystalline alloy prepared at low cooling rate can achieve excellent soft magnetic properties with low HR annealing.