The tracer diffusion of 48V in ferritic alloys was measured by using the serial sectioning method (table 69). It was found that varying the Cr concentration from 8 to 12wt%, or adding up to 0.17wt%C, or alloying with small amounts of other elements, did not have any significant effect upon the V tracer diffusion coefficient. The temperature dependence of the diffusion coefficients revealed the magnetic diffusion anomaly. It was fitted by using the semi-empirical Jonsson equation. This could be taken to be a convenient interpolation formula for the rapid calculation of V diffusivities in ferritic steels with 8 to 12%Cr. The V tracer diffusivities were higher, by a factor of about 1.8, than those of W.
J.Čermák, J.Ruzicková, A.Pokorná: Scripta Metallurgica et Materialia, 1995, 33[7], 1069-73
Table 69
Diffusivity of 48V in Fe-Cr Alloys
Cr (at%) | Temperature (K) | D (m2/s) |
8.07 | 863 | 1.25 x 10-19 |
8.07 | 923 | 1.06 x 10-18 |
8.07 | 983 | 2.15 x 10-17 |
8.07 | 1043 | 2.23 x 10-16 |
8.07 | 1103 | 1.54 x 10-15 |
10.18 | 863 | 8.74 x 10-20 |
10.18 | 923 | 1.35 x 10-18 |
10.18 | 983 | 2.15 x 10-17 |
10.18 | 1043 | 3.95 x 10-16 |
10.18 | 1103 | 1.02 x 10-15 |
continued
Table 69 (continued)
Diffusivity of 48V in Fe-Cr Alloys
Cr (at%) | Temperature (K) | D (m2/s) |
12.25 | 863 | 7.81 x 10-20 |
12.25 | 923 | 1.44 x 10-18 |
12.25 | 983 | 2.03 x 10-17 |
12.25 | 1043 | 3.10 x 10-16 |
12.25 | 1103 | 1.12 x 10-15 |
8.03 | 863 | 7.31 x 10-20 |
8.03 | 923 | 1.94 x 10-18 |
8.03 | 983 | 1.93 x 10-17 |
8.36 | 863 | 1.06 x 10-19 |
8.36 | 923 | 2.08 x 10-18 |
8.36 | 983 | 2.12 x 10-17 |
8.50 | 863 | 1.21 x 10-19 |
8.50 | 923 | 1.10 x 10-18 |
8.50 | 983 | 6.03 x 10-17 |