The magnetic properties of ultrathin Fe-based nanocrystalline alloy obtained by flash annealing

In an effort to obtain soft magnetic materials with excellent high-frequency characteristics, effects of flash annealing on magnetic properties and microstructure in melt-spun Fe-B-Nb-Cu alloy with ultrathin ribbon shape less than 10 μm thickness were investigated. The alloy subjected to optimum annealing treatment showed higher effective permeability and smaller magnetic core loss at 1 MHz than conventionally annealed alloy. The enhanced magnetic properties of the flash-annealed alloy were attributed to the reduced α-Fe phase grain size to 6 nm and the lower remanence ratio of about 0.3 in comparison to the conventionally annealed alloy with the values of 9 nm and 0.7, respectively. The results show that the flash annealing technique was effective in improving the high-frequency soft magnetic properties of Fe-B-Nb-Cu nanocrystalline alloy.