The changes in microstructure and magnetic properties upon crystallization were investigated for melt-spun amorphous Fe-M-B-Cu (M = Ti, Nb or Ta) quaternary alloys. A mostly single bcc phase with nanoscale grain size of about 10 nm was formed by annealing the amorphous Fe-M-B-Cu alloys for 3.6 ks in the range of 750 to 950 K. The crystallization-induced bcc alloys were found to exhibit a high permeability (/¿e) of from 10000 to 20000 at 1 kHz, combined with a high saturation magnetization (Bs) of from 1.40 to 1.55 T. These values are superior to those for amorphous Fe-Si-B alloys which are a known soft magnetic material with high Bs.
- Amorphous phase
- Bcc phase
- High saturation magnetization
- Nanocrystalline structure
- Soft magnetic property