Curie temperature of amorphous Fe-Si-B and Fe-W-Si-B alloys

The effects of composition, annealing temperature and time, annealing heating rate on the Curie temperature of amorphous Fe-Si-B and Fe-W-Si-B alloys were studied. The results indicate that the Curie temperature of these alloys increases with the increase of the metalloid content when it is <25 at%, and then decreases with the further increase of the metalloid content. For amorphous Fe-Si-B and Fe-W-Si-B alloys with the low metalloid content, the Curie temperature increases with the annealing temperature and the annealing time. However, for the amorphous Fe-W-Si-B alloys with the high metalloid content, the Curie temperature increases at low annealing temperature and with short annealing time, and decreases at high annealing temperature and with long annealing time. The heating rate in measuring Curie temperature also influences the Curie temperature of the alloys. The Curie temperature rises at lower heating rates.