Effects of annealing temperature on the microstructure and initial permeability of nanocrystalline alloy Fe73.5Cu1Mo3Si13.5B9

The effects of annealing temperature on the microstructure and initial permeability of nanocrystalline alloy Fe73.5Cu1Mo3Si13.5B9 have been investigated using x-ray diffraction (XRD) and transmission election microscopy (TEM) in this paper. In the annealing temperature range of 460–540 °C, the crystalline phase in the nanocrystalline alloy Fe73.5Cu1Mo3Si13.5B9 is the α-Fe(Si) with a DO3 superstructure, and it has a grain size of,14 nm. The volume fraction, Si content, and degree of order of the α-Fe(Si) phase increase with increasing the annealing temperature. The DO3 ordered region in the a-Fe(Si) grain is approximately spherical; its size increases as the annealing temperature increases. There is an obvious change in the microstructure of the residual amorphous phase with the annealing temperature. Both the microstructure of the α-Fe(Si) phase and that of the residual amorphous phase have effects on the initial permeability of nanocrystalline alloy Fe73.5Cu1Mo3Si13.5B9.