Structural changes of annealed metallic glass Co78Si9B13

The transition of the metallic glass CO78Si9B13 from the amorphous to the crystalline state has been investigated. The samples were subjected to isochronous annealing (4 h) in the temperature range from 573 to 823 K in an argon atmosphere. After each anneal structural changes were measured by X-ray diffraction. The electrical and Hall resistivities of the samples were also measured. The electrical resistivity decreased when the temperature of the anneal increased. The Hall resistivities decreased in the samples in which, after the anneal, a crystalline phase was created from the amorphous matrix. Investigations proved that the annealing of the samples leads to a first order phase transition; phases which appear after the annealing are alpha-Co and Co2B. Moreover, it is shown that annealing at a temperature of 648 K causes the appearance of clusters within the range of the amorphous phase. (C) 1998 Elsevier Science B.V. All rights reserved.