The diffusion coefficients were measured in the α-phase of Fe-free binary alloys at temperatures ranging from 830 to 1100K (tables 364 and 365). The diffusivity values for the 2 alloys were essentially indistinguishable and were little different to published diffusion coefficients for Hf in Fe-free polycrystalline samples of α-Zr. The temperature dependence of the diffusivity in the alloys was characteristic of that in the bulk of intrinsic α-Zr:
D(m2/s)=5 x 10-7exp[-2.7(eV)/kT]
The present Hf diffusivity values were much lower than the corresponding values which were measured in commercial Zr-2.5Nb alloy. This difference was attributed to the effect of Fe in solid solution. Also, the absence of a strong Nb-induced enhancement of Hf diffusion in α-Zr suggested that intrinsic Nb diffusion in α-Zr might not be controlled by a normal vacancy mechanism.
H.Zou, G.M.Hood, J.A.Roy, R.J.Schultz, J.A.Jackman: Philosophical Magazine A, 1995, 71[4], 901-6
Table 357
Diffusivity of Fe in Zr41Be20Ti16.5Cu12.5Ni10
Temperature (K) | Diffusivity (m2/s) |
513 | 3.97 x 10-24 |
533 | 1.51 x 10-23 |
551 | 2.93 x 10-23 |
555 | 3.53 x 10-22 |
573 | 4.23 x 10-22 |
585 | 6.35 x 10-22 |
612 | 2.29 x 10-21 |
628 | 7.77 x 10-21 |
642 | 8.07 x 10-20 |
653 | 7.80 x 10-20 |
657 | 2.12 x 10-19 |
Table 358
Diffusivity of B in Zr46.8Be27.5Ti8.2Cu7.5Ni10
Temperature (K) | Diffusivity (m2/s) |
513 | 8.49 x 10-23 |
534 | 4.18 x 10-22 |
554 | 1.77 x 10-21 |
574 | 7.77 x 10-21 |
593 | 2.90 x 10-20 |
613 | 1.59 x 10-19 |
630 | 5.55 x 10-19 |
643 | 1.42 x 10-18 |
658 | 4.11 x 10-18 |
672 | 1.20 x 10-17 |
Table 359
Diffusivity of Fe in Zr46.8Be27.5Ti8.2Cu7.5Ni10
Temperature (K) | Diffusivity (m2/s) |
513 | 2.14 x 10-24 |
534 | 2.60 x 10-23 |
554 | 1.15 x 10-22 |
574 | 6.13 x 10-22 |
593 | 3.88 x 10-21 |
613 | 2.92 x 10-20 |
630 | 1.51 x 10-19 |
643 | 4.22 x 10-19 |
658 | 1.66 x 10-18 |
672 | 5.98 x 10-18 |
Table 360
Diffusivity of Co in Zr46.8Be27.5Ti8.2Cu7.5Ni10
Temperature (K) | Diffusivity (m2/s) |
513 | 1.32 x 10-23 |
533 | 4.05 x 10-23 |
554 | 4.86 x 10-22 |
573 | 1.41 x 10-21 |
593 | 8.98 x 10-21 |
614 | 5.27 x 10-20 |
628 | 2.51 x 10-19 |
642 | 9.20 x 10-19 |
658 | 2.88 x 10-18 |
673 | 1.10 x 10-17 |