Effect of super-heat treatment and quenching wheel speed on the structure and magnetic properties of Fe-Si-Nb-Cu-B-Al-Ge melt spun ribbons

In this work an attempt is made to study the effect of super-heat temperature and quenching wheel speed on the structure and magnetic properties of the Al/Ge substituted FINEMET alloy. In this respect, various as-spun ribbons were prepared at two different superheat temperatures (150 and 250 degrees C) and various quenching wheel speeds (20, 30 and 40 m/s). Based on the results obtained, it was shown that both the super-heat temperature and wheel speed play an important role in the control of the level of amorphicity and of magnetic properties of the as-spun ribbons. Further, it was seen that the higher was the super-heat temperature/quenching wheel speed the higher was the degree of amorphicity giving rise to a lower magnetic saturation induction/magnetic permeability and higher coercivity for the ribbons prepared. (C) 2007 Elsevier B.V. All rights reserved.