Interdiffusion coefficients were deduced (table 1) by means of Boltzmann-Matano analyses of the concentration profiles or by monitoring the thickness or resistance of diffusion cells as a function of time. It was found that the results which were obtained using the 3 methods agreed in the case of Ag0.5Cu0.5I solid solution. The interdiffusion coefficients were of the order of 10-7cm2/s for temperatures ranging from 570 to 620K. The general shapes of the concentration profiles indicated that Cu ion diffusivity made a greater contribution, in that the Cu concentration at the Ag-rich side was higher than the Ag concentration at the Cu-rich side. That is, more Cu than Ag diffused through the interfacial zone. This was in accord with a proposed co-ionic conductivity of the solid solution.

J.C.Bazán, R.S.Pettigrosso: Journal of Materials Science, 1996, 31[15], 4077-80

 

 

 

 

Table 1

Interdiffusion in AgI/CuI Couples

 

 

Temperature (K)

 

Method

 

D (cm2/s)

 

 

571

 

resistance

 

7.70 x 10-8

588

resistance

1.60 x 10-7

603

resistance

2.40 x 10-7

578

thickness

1.40 x 10-7

588

thickness

1.60 x 10-7

602

thickness

1.70 x 10-7

619

thickness

7.10 x 10-7