Structural Stability of Amorphous Alloy of Modified Finemet Type

The Finemet type amorphous alloys are well known as high frequency soft magnetic materials. They have good soft magnetic properties which are characterized by low coercive force and high permeability because of the lack of crystalline anisotropy. The structural stability of the amorphous ribbon of Finemet type modified by Mn, Al and Cr prepared by melt-spinning process was studied using differential scanning calorimetry and dynamical mechanical analysis. With increase of the crystalline portion in the sample, the Curie transition is shifted to the higher temperatures. The magnetic relaxation processes at frequencies above 10⁴ Hz were detected by mass magnetic susceptibility measurement.