The migration of Cu and Ti in amorphous samples was measured, at temperatures ranging from 573 to 645K, by using secondary ion mass spectrometry. The experiments were performed on pre-relaxed specimens, and the diffusion coefficients were found to lie between 3.0 x 10-24 and 9.0 x 10-21m2/s. The temperature dependence of the diffusivity was of Arrhenius type, and the data for Cu diffusion (table 78) and Ti diffusion (table 79) could be described by:

Cu:     D (m2/s) = 1.3 x 101exp[-2.73(eV/atom)/kT]

Ti:     D (m2/s) = 8.5 x 108exp[-3.82(eV/atom)/kT]

The results suggested the possible existence of a size-dependence of the diffusivity.

S.K.Sharma, M.P.Macht, V.Naundorf: Physica Status Solidi A, 1991, 126[1], 101-8

 

Table 78

Diffusion of Cu in Fe40Ni40B20

Temperature (K)

D (m2/s)

573

2.4 x 10-23

588

6.8 x 10-23

593

7.4 x 10-23

597

1.1 x 10-22

609

3.1 x 10-22

611

2.7 x 10-22

618

1.0 x 10-21

622

9.1 x 10-22

632

2.4 x 10-21

638

2.7 x 10-21

643

5.1 x 10-21

646

8.6 x 10-21