Magnetic properties, anisotropy, and domain structure of Fe-based nanocrystalline alloy induced by continuous stress-annealing treatment

The effect of tensile annealing temperature (Ta) on microstructure, soft magnetic properties, magnetic anisotropy, and domain structure for the Finemet nanocrystalline alloy prepared using a home-made continuous tension annealing equipment has been investigated in detail. Results show that the Ta has a great influence on the magnetic properties of the nanocrystalline alloy by affecting its stress-induced anisotropy constant (Ku), average domain width between the strip-like domain patterns (dw) and domain-wall energy (gamma w). Hereinto, the average anisotropy constant < K > is absolutely dominated by the Ku under the given Ta range with a constant tension stress of 49.1 MPa. The effective permeability (mu e) exhibits a completely opposite variation trend to the physical parameters of Ku, dw and gamma w. The corresponding total core loss decreases first and then increases, which is mainly due to the variation of hysteresis loss with the increasing Ta. These results are helpful to obtain the stressannealed nanocrystalline alloy with excellent soft magnetic properties for the preparation of high-precision and low-loss current transformers.