High-temperature soft magnetic behavior of magnetic field annealed Finemet-type nanocrystalline alloys

The soft magnetic behaviors at elevated temperatures for magnetic field annealed nanocrystalline Fe73.5Cu1Nb3Si13.5B9, (Fe0.5Co0.5)73.5Cu1Nb3Si13.5B9 and Ni10(Fe0.5Co0.5)63.5Cu1Nb3Si13.5B9 alloys were investigated by the temperature evolution of initial permeability (μi-T curve). The results show that magnetic field annealing gives rise to a persistent increasing μi from room temperature to a relatively higher temperature for Co- and NiCo-containing Finemet. Especially for the magnetic field annealed NiCo-containing Finemet, the μi is evidently improved in the temperature range between 200-600°C with respect to the sample without magnetic field annealing.