The diffusion coefficients in the core of boundary regions were deduced from changes, in the intensity of the radiation that was emitted by atomic probes, as a function of the annealing time and temperature. The Arrhenius relationship which characterized the temperature dependence of 57Cd diffusion in the core of the so-called crystallite conjugation regions of polycrystalline W was found to be:

D (m2/s) = 2.5 x 10-10exp[-132.9(kJ/mol)/RT]

S.M.Klotsman, M.I.Kurkin, V.N.Kaigorodov, V.V.Dyakin, M.S.Dudarev: Physics of Metals and Metallography, 1996, 82[1], 67-70

 

 

 

Table 170

Diffusion of 57Co in W Monocrystals

 

Temperature (K)

D (cm2/s)

2265

6.11 x 10-13

2144

1.30 x 10-13

2080

6.03 x 10-14

1984

1.23 x 10-14

1861

1.49 x 10-15

1773

3.23 x 10-16

1684

8.24 x 10-17

1573

9.56 x 10-16

1561

3.47 x 10-17