The plastic flow has been investigated for Co-base amorphous alloys with some additive elements, Fe3Co71Si8B16M2 from creep measurement employing a constant heating rate method near the glass transition temperature. The activation energy in the creep process was found to be proportional to the atomic volume of the additive elements which were determined from the Goldschmidt radius. The observed activation energy was changed from 1.92 eV to 2.53 eV in Co (1.25 Å) and Nb (1.47 Å), respectively.
The field induced anisotropy energy Ku hes been measured for the same alloy series. It was found that Ku decreased with the increasing of the atomic volume of the non-magnetic additive elements. In the case of nearly the same atomic volume of the additive elements, Ku seems to depend on the strength of the magnetic interaction. From these results, the degree of the rearrangement of the atoms and the magnetic interaction between magnetic atoms play a dominant role in the field induced magnetic anisotropy.
