Influence of microstructure on soft magnetic properties of low coreloss and high Bs Fe85Si2B8P4Cu1 nanocrystalline alloy

Microstructure and magnetic properties of high B-s Fe85Si2B8P4Cu1 nano-crystalline alloy were tailored. The B-s similar to 1.85 T and low coercivity H-c similar to 6 A/m were obtained by conventional annealing (i.e., one step) at a heating rate of similar to 400 degrees C/min. While one step annealing process produces a fairly stable nanostructure, for short times at temperatures <425 degrees C, the nanostructure and concomitant magnetic properties of this alloy are shown to be tunable by two step annealing process. Nanocrystalline ribbons with grain size (D) ranging from similar to 15 to 32 nm, H-c similar to 6 to 140 A/m and core-loss at 1.5 T, 50 Hz similar to 0.39 similar to 5.0 W/kg were obtained. The H-c of Fe85Si2B8P4Cu1 alloy is shown to vary as D-6, but a small deviation was noticed, which may be due to weak anisotropy. (C) 2014 AIP Publishing LLC.