The diffusion of O was studied in liquid alloys which were used as precursors in the preparation of superconducting thin films via the liquid-gas solidification method. The diffusivities were measured by using a coulometric titration technique. It was found that the diffusivities were of the order of 0.0001 to 0.001cm2/s, and that the logarithm of the O diffusivity was inversely proportional to the logarithm of the O concentration (tables 97 and 98). It was suggested that an interstitial diffusion mechanism contributed to the rapid O migration, and that strong bonds between Ba and O enhanced the configurational structural order and accelerated O diffusion.

H.Chou, T.C.Chow, H.S.Chen: Journal of Applied Physics, 1995, 78[5], 3511-3

Table 96

Diffusivity of O in Liquid Cu0.65Ba0.35 at 900C

 

C (at%)

D (cm2/s)

0.00244

2.953 x 10-4

0.00194

3.734 x 10-4

0.00152

3.337 x 10-4

0.001077

4.595 x 10-4

0.000972

4.511 x 10-4

0.000331

4.574 x 10-4

0.000252

5.571 x 10-4

0.000204

6.225 x 10-4

0.000167

6.46 x 10-4

0.000128

7.267 x 10-4

0.000105

7.734 x 10-4

0.00007

8.623 x 10-4