The bulk diffusion of 110Ag at 88 to 227C was reported (table 220). Due to the low solubility of Ag in Pb, Fick’s solution corresponding to the boundary condition - of a constant solute concentration at the surface - was used. Since Ag penetration profiles in pure Pb gave diffusion coefficients which were independent of the penetration depth and the Ag concentration, it was suggested that a slight decrease in Ag diffusivity in Pb-Ag solid solutions was of no significance. This implied that the interstitial Ag atoms did not associate significantly with each other to form Ag-Ag dimers.

H.Amenzou-Badrour, G.Moya, J.Bernardini: Acta Metallurgica, 1988, 36[3], 767-74

 

Table 221

Diffusivity of Au in Pb under Microgravity Conditions

 

Temperature (C)

Conditions

D (cm2/s)

363

micro-gravity

2.27 x 10-5

363

terrestrial

3.81 x 10-5

400

terrestrial

3.53 x 10-5

437

micro-gravity

3.03 x 10-5

437

terrestrial

3.35 x 10-5

450

micro-gravity

3.40 x 10-5

450

terrestrial

3.79 x 10-5

475

terrestrial

4.19 x 10-5

500

terrestrial

4.89 x 10-5

538

terrestrial

5.19 x 10-5

538

micro-gravity

4.23 x 10-5

550

micro-gravity

4.40 x 10-5

615

terrestrial

5.96 x 10-5

670

terrestrial

6.39 x 10-5

700

micro-gravity

5.80 x 10-5

850

terrestrial

9.10 x 10-5

850

micro-gravity

7.95 x 10-5