The magnetic after-effect spectra of H-charged amorphous alloys were studied at temperatures of between 4.2 and 480K. In the case of partially crystallized samples, a single broadened asymmetrical relaxation maximum was observed. With decreasing H content, there was a shift in the maximum temperature from 140 to 196K. This was attributed to an increase, in the average activation enthalpy, from 0.33 to 0.49eV. It was assumed that H diffusion in the amorphous alloys involved a broad distribution of equilibrium sites, as well as saddle-point energies. The H-induced relaxation maxima, and their annealing behavior, was thus attributed to local H jumps. Long-range H diffusion at temperatures above 300K was also measured by means of thermal de-gassing at various heating rates. The results (table 85) showed that long-range diffusion was governed by H atoms in the amorphous phase.

C.U.Maier, H.Kronmüller: Physica Status Solidi B, 1991, 168[2], 425-35

 

 

 

Table 85

Parameters for H Diffusion in Fe90Zr10

 

Condition

Do (m2/s)

E (eV)

100% amorphous

1 x 10-6

0.55

90% amorphous

1 x 10-6

0.56

50% amorphous

4 x 10-8

0.44