Effect of Continuous Stress-annealing on the Structure and Magnetic Properties of Fe72.9Si15.8B6.9Nb3.2Cu1Co0.2 Amorphous Alloy.

The induced magnetic anisotropy, domain structure and magnetic properties of nanocrystallized Fe_72.9Si_15.8B_6.9Nb_3.2Cu₁Co_0.2 materials by continuous stress-annealing at 803–903 K under 0–75 MPa were systematically investigated. It was found that the tensile stress applied during annealing is beneficial to reduce the coercivity and core loss by refining the grain size of α-Fe phase. The remanence and permeability for the annealed samples at 853–903 K are negatively correlated with the induced anisotropy, which increases with the applied tensile stress. The stress-annealed samples yield magnetic easy plane perpendicular to the stress axis with an induced anisotropy constant greater than 1200 J/m³. The nanocrystalline cores with a low AC coercivity of 6.0 A/m and low core loss of 16.1 W/kg in combination with a high DC bias capability was successfully fabricated by stress-annealing the amorphous precursor at 878 K under 40 MPa. The current nanocrystalline material has potential for the application as anti-DC transformers in the electronic field. [ABSTRACT FROM AUTHOR]